What to know about COVID-19 symptoms in children


Although there are notable exceptions, most evidence suggests that COVID-19 is much less dangerous for children than it is for adults and infants.

Knowing the symptoms of COVID-19 in children can help parents and caregivers identify the emergency warning signs and seek appropriate care.

This article covers the symptoms of COVID-19 in children, some potential complications, and when to see a doctor.

Symptoms of COVID-19 in children

Data from both China and the United States on children with SARS-CoV-2, the virus that causes COVID-19, suggest that the risk of severe illness is lower in children than it is in adults.

A study of 2,752 cases of COVID-19 in children found that three had died, though the exact cause of death in each case is under investigation.

Current evidence suggests that infants have a higher rate of hospitalization, with some requiring treatment in intensive care units.

In China, more than 90% of children with COVID-19 had no symptoms and only mild-to-moderate disease.

The following are some symptoms that children may experience:

  • Fever: Although most adults report a fever with COVID-19, fevers are slightly less common among children, according to data from the Centers for Disease Control and Prevention (CDC).
  • Flu-like symptoms: Around 73% of children with COVID-19 had a fever, cough, or shortness of breath. Shortness of breath is much less common in children. In one analysis, 43% of adults and just 13% of children had this symptom.
  • Respiratory tract symptoms: Children with mild forms of the illness may develop a runny nose, cough, or sore throat.
  • Digestive symptoms: Some children develop vomiting, diarrhea, or nausea.
  • Changes in the sense of smell: A 2020 analysis found that most adults with COVID-19 lose their sense of smell. Researchers have not assessed this symptom in young people, but children may also lose their sense of taste or smell.
  • Pain: Children with COVID-19 may develop muscle pain or a headache.
  • Behavioral changes: Children may be moody or cry more often, especially if they are too young to verbally express their emotions or identify their symptoms. Some children may also be anxious, especially if they know that COVID-19 can be dangerous.

Overall, COVID-19 symptoms tend to be less severe in children. Children are also less likely than adults to report each symptom.

Complications

Children with underlying health conditions — such as lung disease, heart disease, or a weak immune system — are more susceptible to serious COVID-19 complications.

A CDC study that assessed COVID-19 symptoms in children used data on hospitalization and underlying medical conditions for 295 children. In that group, 77% of hospitalized children had at least one other medical condition. This suggests that comorbidities are a significant risk factor for hospitalization in children.

Even among high risk children, however, the risk of dying from COVID-19 is very low. Of 2,143 children included in a Chinese CDC study, just one 14-year-old died. Also, as above, 3 out of 2,572 children in a CDC study died, though the cause in each case is currently unconfirmed.

Some other potential complications include:

  • organ failure
  • the need to use a ventilator
  • sepsis, which is a severe infection that affects many systems in the body
  • heart failure
  • issues that can cause life threatening blood clots

Children with severe symptoms usually develop them within a week of getting sick.

A small number of children have also developed symptoms of multisystem inflammatory syndrome in children (MIS-C). This syndrome can cause symptoms that resemble those of toxic shock syndrome and Kawasaki disease. Without treatment, it may be fatal.

Children with MIS-C may develop a rash, stomach pain, bloodshot eyes, exhaustion, diarrhea, or vomiting.

The following symptoms require emergency medical attention:

  • confusion
  • fever
  • chest pressure or pain
  • neck pain
  • difficulty breathing
  • blue or white face, fingers, or toes
  • an inability to stay awake
  • severe stomach pain

When to see a doctor

Most children have either no symptoms or only mild-to-moderate ones. These children do not need to go to the hospital or see a doctor.

However, parents and caregivers should call a pediatrician if their child shows any symptoms of COVID-19. The pediatrician can offer advice on which symptoms to watch and some suggestions for home treatment.

In some areas, a child may also need a referral for COVID-19 testing.

Call a doctor if:

  • the child seems very ill
  • they develop a rash
  • their symptoms get better and then get worse again
  • they recover from COVID-19 but then develop inflammatory symptoms, such as a rash, fever, or bloodshot eyes

Go to the emergency room if a child:

  • gasps for air or shows signs of respiratory distress, such as bluish lips, breathing very fast, or difficulty breathing
  • seems confused, seems lethargic, or cannot wake up
  • reports pressure or pain in their chest
  • has symptoms of organ failure, such as intense pain in the stomach, difficulty passing urine, an inability to move without help, or an inability to think clearly

Treatment

No medication can cure COVID-19. Although hospitals and researchers are exploring experimental treatments, these are currently only available to very sick people.

Most children can recover with home treatment. To help a child with COVID-19:

  • Encourage them to rest.
  • Give them lots of fluids to prevent dehydration.
  • Check on them regularly to ensure that they are not getting worse.
  • Ask a doctor about over-the-counter pain and fever relievers.
  • Have them stay in a single area of the house, if possible. Clean and disinfect all surfaces they touch, and encourage other family members to avoid them. Also, wear a face mask when caring for a sick child.

Parents and caregivers may find these guidelines challenging to follow when caring for a child or infant. The CDC offer some advice on how to manage risk around children.

It may also be a good idea to speak to a medical professional about how best to care for a child with a suspected SARS-CoV-2 infection. Children under 2 years of age should not wear a face covering.

Very sick children may need to go to the hospital. In the hospital, doctors will focus on managing the child’s symptoms. They might need oxygen, intravenous fluids, or steroid medications to help them breathe.

Rarely, a child might need a ventilator if they cannot breathe well on their own.

15 natural ways to lower your blood pressure


High blood pressure is a dangerous condition that can damage your heart. It affects one in three people in the US and 1 billion people worldwide.

If left uncontrolled, high blood pressure raises your risk of heart disease and stroke.

But there’s good news. There are a number of things you can do to lower your blood pressure naturally, even without medication.

Here are 15 natural ways to combat high blood pressure.

1. Walk and exercise regularly

Exercise is one of the best things you can do to lower high blood pressure.

Regular exercise helps make your heart stronger and more efficient at pumping blood, which lowers the pressure in your arteries.

In fact, 150 minutes of moderate exercise, such as walking, or 75 minutes of vigorous exercise, such as running, per week, can help lower blood pressure and improve your heart health.

What’s more, doing even more exercise than this reduces your blood pressure even further, according to the National Walkers’ Health Study.

Bottom line: Walking just 30 minutes a day can help lower your blood pressure. More exercise helps reduce it even further.

2. Reduce your sodium intake

Salt intake is high around the world. In large part, this is due to processed and prepared foods.

For this reason, many public health efforts are aimed at lowering salt in the food industry.

Many studies have linked high salt intake with high blood pressure and heart events, including stroke.

However, more recent research indicates that the relationship between sodium and high blood pressure is less clear.

One reason for this may be genetic differences in how people process sodium. About half of people with high blood pressure and a quarter of people with normal levels seem to have a sensitivity to salt.

If you already have high blood pressure, it’s worth cutting back your sodium intake to see if it makes a difference. Swap out processed foods with fresh ones and try seasoning with herbs and spices rather than salt.

Bottom line: Most guidelines for lowering blood pressure recommend reducing sodium intake. However, that recommendation might make the most sense for people who are salt-sensitive.

3. Drink less alcohol

Drinking alcohol can raise blood pressure. In fact, alcohol is linked to 16% of high blood pressure cases around the world.

While some research has suggested that low-to-moderate amounts of alcohol may protect the heart, those benefits may be offset by adverse effects.

In the U.S., moderate alcohol consumption is defined as no more than one drink a day for women and two for men. If you drink more than that, cut back.

Bottom line: Drinking alcohol in any quantity may raise your blood pressure. Limit your drinking in line with the recommendations.

4. Eat more potassium-rich foods

Potassium is an important mineral.

It helps your body get rid of sodium and eases pressure on your blood vessels.

Modern diets have increased most people’s sodium intake while decreasing potassium intake.

To get a better balance of potassium to sodium in your diet, focus on eating fewer processed foods and more fresh, whole foods.

Foods that are particularly high in potassium include:

  • vegetables, especially leafy greens, tomatoes, potatoes, and sweet potatoes
  • fruit, including melons, bananas, avocados, oranges, and apricots
  • dairy, such as milk and yogurt
  • tuna and salmon
  • nuts and seeds
  • beans

Bottom line: Eating fresh fruits and vegetables, which are rich in potassium, can help lower blood pressure.

5. Cut back on caffeine

If you’ve ever downed a cup of coffee before you’ve had your blood pressure taken, you’ll know that caffeine causes an instant boost.

However, there’s not a lot of evidence to suggest that drinking caffeine regularly can cause a lasting increase.

In fact, people who drink caffeinated coffee and tea tend to have a lower risk of heart disease, including high blood pressure, than those who don’t drink it.

Caffeine may have a stronger effect on people who don’t consume it regularly.

If you suspect you’re caffeine-sensitive, cut back to see if it lowers your blood pressure.

Bottom line: Caffeine can cause a short-term spike in blood pressure, although for many people, it does not cause a lasting increase.

6. Learn to manage stress

Stress is a key driver of high blood pressure.

When you’re chronically stressed, your body is in a constant fight-or-flight mode. On a physical level, that means a faster heart rate and constricted blood vessels.

When you experience stress, you might also be more likely to engage in other behaviors, such as drinking alcohol or eating unhealthful food that can adversely affect blood pressure.

Several studies have explored how reducing stress can help lower blood pressure. Here are two evidence-based tips to try:

  • Listen to soothing music: Calming music can help relax your nervous system. Research has shown it’s an effective complement to other blood pressure therapies.
  • Work less: Working a lot, and stressful work situations, in general, are linked to high blood pressure.

Bottom line: Chronic stress can contribute to high blood pressure. Finding ways to manage stress can help.

7. Eat dark chocolate or cocoa

Here’s a piece of advice you can really get behind.

While eating massive amounts of dark chocolate probably won’t help your heart, small amounts may.

That’s because dark chocolate and cocoa powder are rich in flavonoids, which are plant compounds that cause blood vessels to dilate.

A review of studies found that flavonoid-rich cocoa improved several markers of heart health over the short term, including lowering blood pressure.

For the strongest effects, use non-alkalized cocoa powder, which is especially high in flavonoids and has no added sugars.

Bottom line: Dark chocolate and cocoa powder contain plant compounds that help relax blood vessels, lowering blood pressure.

8. Lose weight

In people with overweight, losing weight can make a big difference to heart health.

According to a 2016 study, losing 5% of your body mass could significantly lower high blood pressure.

In previous studies, losing 17.64 pounds (8 kilograms) was linked to lowering systolic blood pressure by 8.5 mm Hg and diastolic blood pressure by 6.5 mm Hg.

To put that in perspective, a healthy reading should be less than 120/80 mm Hg.

The effect is even greater when weight loss is paired with exercise.

Losing weight can help your blood vessels do a better job of expanding and contracting, making it easier for the left ventricle of the heart to pump blood.

Bottom line: Losing weight can significantly lower high blood pressure. This effect is even more significant when you exercise.

9. Quit smoking

Among the many reasons to quit smoking is that the habit is a strong risk factor for heart disease.

Every puff of cigarette smoke causes a slight, temporary increase in blood pressure. The chemicals in tobacco are also known to damage blood vessels.

Surprisingly, studies haven’t found a conclusive link between smoking and high blood pressure. Perhaps this is because smokers develop a tolerance over time.

Still, since both smoking and high blood pressure raise the risk of heart disease, quitting smoking can help lessen that risk.

Bottom line: There’s conflicting research about smoking and high blood pressure, but what is clear is that both increase the risk of heart disease.

10. Cut added sugar and refined carbs

There’s a growing body of research showing a link between added sugar and high blood pressure.

In the Framingham Women’s Health Study, women who drank even one soda per day had higher levels than those who drank less than one soda per day.

Another study found that having one less sugar-sweetened beverage per day was linked to lower blood pressure.

And it’s not just sugar — all refined carbs, such as the kind found in white flour — convert rapidly to sugar in your bloodstream and may cause problems.

Some studies have shown that low carb diets may also help reduce blood pressure.

One study on people undergoing statin therapy found that those who went on a 6-week, carb-restricted diet saw a greater improvement in blood pressure and other heart disease markers than people who did not restrict carbs.

Bottom line: Refined carbs, especially sugar, may raise blood pressure. Some studies have shown that low carb diets may help reduce your levels.

11. Eat berries

Berries are full of more than just juicy flavor.

They’re also packed with polyphenols, natural plant compounds that are good for your heart.

Polyphenols can reduce the risk of stroke, heart conditions, and diabetes, as well as improving blood pressure, insulin resistance, and systemic inflammation.

One study assigned people with high blood pressure to a low-polyphenol diet or a high-polyphenol diet containing berries, chocolate, fruits, and vegetables.

Those consuming berries and polyphenol-rich foods experienced improved markers of heart disease risk.

Bottom line: Berries are rich in polyphenols, which can help lower blood pressure and the overall risk of heart disease.

12. Try meditation or deep breathing

While these two behaviors could also fall under “stress reduction techniques,” meditation and deep breathing deserve specific mention.

Both meditation and deep breathing may activate the parasympathetic nervous system. This system is engaged when the body relaxes, slowing the heart rate, and lowering blood pressure.

There’s quite a bit of research in this area, with studies showing that different styles of meditation appear to have benefits for lowering blood pressure.

Deep breathing techniques can also be quite effective.

In one study, participants were asked to either take six deep breaths over the course of 30 seconds or simply sit still for 30 seconds. Those who took breaths lowered their blood pressure more than those who just sat.

Try guided meditation or deep breathing. Here’s a video to get you started.

Bottom line: Both meditation and deep breathing can activate the parasympathetic nervous system, which helps slow your heart rate and lower blood pressure.

13. Eat calcium-rich foods

People with low calcium intake often have high blood pressure.

While calcium supplements haven’t been conclusively shown to lower blood pressure, calcium-rich diets do seem linked to healthful levels.

For most adults, the calcium recommendation is 1,000 milligrams (mg) per day. For women over 50 and men over 70, it’s 1,200 mg per day.

In addition to dairy, you can get calcium from collard greens and other leafy greens, beans, sardines, and tofu. Here is a list of calcium-rich plant-based foods.

Bottom line: Calcium-rich diets are linked to healthy blood pressure levels. You can get calcium through eating dark leafy greens and tofu, as well as dairy.

14. Take natural supplements

Some natural supplements may also help lower blood pressure. Here are some of the main supplements that have evidence behind them:

  • Aged garlic extract: Researchers have used aged garlic extract successfully as a stand-alone treatment and along with conventional therapies for lowering blood pressure.
  • Berberine: Traditionally used in Ayurvedic and Chinese medicine, berberine may increase nitric oxide production, which helps decrease blood pressure.
  • Whey protein: A 2016 study found that whey protein improved blood pressure and blood vessel function in 38 participants.
  • Fish oil: Long credited with improving heart health, fish oil may benefit people with high blood pressure the most.
  • Hibiscus: Hibiscus flowers make a tasty tea. They’re rich in anthocyanins and polyphenols that are good for your heart and may lower blood pressure.

Bottom line: Researchers have investigated several natural supplements for their ability to lower blood pressure.

15. Eat foods rich in magnesium

Magnesium is an important mineral that helps blood vessels relax.

While magnesium deficiency is pretty rare, many people don’t get enough.

Some studies have suggested that getting too little magnesium is linked with high blood pressure, but evidence from clinical studies has been less clear.

Still, eating a magnesium-rich diet is a recommended way to ward off high blood pressure.

You can incorporate magnesium into your diet by consuming vegetables, dairy products, legumes, chicken, meat, and whole grains.

Bottom line: Magnesium is an essential mineral that helps regulate blood pressure. Find it in whole foods, such as legumes and whole grains.

Take home message

High blood pressure affects a large proportion of the world’s population.

While drugs are one way to treat the condition, there are many other natural techniques, including eating certain foods that can help.

Controlling your blood pressure through the methods in this article may, ultimately, help you lower your risk of heart disease

All you need to know about flu

Influenza, or flu, is a respiratory illness that results from a viral infection. Flu is highly contagious and spreads through respiratory droplets. A person can pass it on while talking or through physical contact, such as shaking hands.

Influenza A and influenza B cause seasonal epidemics in the United States and elsewhere every winter. Type C usually causes mild respiratory illness.

Some strains of influenza A, such as the H5N1 “bird flu” virus, occasionally infect humans, causing serious illness. Experts track these strains carefully, as they try to predict how they will change, and how they might affect people.

Symptoms

According to the Centers for Disease Control and Prevention (CDC), a person with flu may experience:

  • a high temperature that lasts 3–4 days
  • a stuffy or runny nose
  • cold sweats and shivers
  • aches that may be severe
  • a headache
  • fatigue

Not everyone with flu will have all of these symptoms. For instance, it is possible to have flu without a fever.

The symptoms of influenza typically come on suddenly. Initially, a person with flu may experience:

  • a high temperature
  • a stuffy or runny nose
  • a dry cough
  • cold sweats and shivers
  • aches that may be severe
  • a headache
  • fatigue, and a feeling of being unwell
  • a low appetite

Flu symptoms in adults

Adults with the following symptoms should seek medical help urgently:

  • breathing difficulties
  • pain or pressure in the chest or abdomen
  • dizziness, confusion, or loss of alertness
  • seizures
  • not urinating, which may indicate dehydration
  • severe pain, weakness, and unsteadiness
  • a fever or cough that goes away and then comes back
  • a worsening of other existing health conditions

Flu symptoms in children

Children often have similar symptoms to adults but can also have gastrointestinal symptoms, such as nausea, vomiting, and diarrhea.

If a child has the following symptoms, they need emergency medical care:

  • breathing difficulties
  • rapid breathing
  • bluish face or lips
  • chest pain or ribs pulling inward as they breathe
  • severe aches
  • dehydration, for example, not urinating for 8 hours and crying dry tears
  • lack of alertness or interaction with others
  • a fever above 104°F or any fever in a child under 12 weeks of age
  • a fever or cough that goes away but then comes back
  • a worsening of any other medical conditions

Should children have flu medication? Find out more here about Tamiflu and its effects on children.

Flu symptoms in babies

Flu can be dangerous for babies. If symptoms appear, a parent or caregiver should seek medical help.

A baby with flu may:

  • be very tired
  • have a cough and sore throat
  • have a stuffy or runny nose
  • have a fever of 100°F or more
  • have vomiting or diarrhea

The baby needs emergency medical attention if they:

  • do not want anyone to hold them
  • have a blue or gray skin color
  • are breathing fast or have difficulty breathing
  • have a fever with a rash
  • have symptoms that go away but come back again
  • show signs of dehydration, for example, not urinating
  • do not wake up or interact
  • have severe and persistent vomiting

Flu type A symptoms

If a person has the following symptoms, they may have influenza type A:

  • fever and chills
  • headache
  • muscle aches
  • fatigue
  • weakness
  • a stuffy or runny nose
  • a sore throat and cough

Flu type B symptoms

Influenza B symptoms are similar to those of influenza A.

Treatment

Most people will be able to treat the flu at home. A combination of lifestyle remedies and over-the-counter medication can help relieve symptoms.

Pain relief medication can help manage a headache and body pains. A healthcare professional can recommend the best options.

Some painkillers, such as aspirin, are not suitable for children under 16 years of age. The use of aspirin at this age can lead to a condition known as Reye’s syndrome.

Flu home remedies

When a person has flu, it is essential that they:

  • stay at home
  • avoid contact with other people if possible
  • keep warm and rest
  • consume plenty of liquids and healthful foods
  • avoid alcohol
  • stop smoking, as this raises the risk of complications

Other things people can try at home include:

  • chicken broth
  • herbal teas
  • vitamin supplements

However, there is not enough evidence available to confirm that consuming these helps.

Flu diagnosis

If a person seeks medical advice for flu symptoms, a doctor will likely ask about their symptoms and do a physical examination. A doctor may also take a throat swab for testing.

The rapid influenza diagnostic test can produce results in 10–15 minutes but may not be accurate. Other, more accurate tests can take longer to give results.

Flu or a cold?

People often confuse the flu with a bad cold, as some symptoms are similar.

A cold and the flu both involve:

  • a runny or blocked nose
  • a sore throat
  • a cough
  • chest discomfort
  • fatigue

However, there are some differences:

  • A cold does not involve a fever, while the flu usually does.
  • The symptoms of a cold tend to appear gradually, while flu symptoms can develop rapidly.
  • Cold symptoms are typically less severe than those of flu.
  • After having the flu, a person may continue to feel tired for several weeks.
  • Flu is more likely to lead to complications, and it can be life threatening.

Flu or food poisoning?

There are many types of viruses, and some can affect the digestive system. People sometimes call this “stomach flu.” This illness is different from influenza, which is a respiratory disease.

The most common cause of “stomach flu” is the norovirus, which enters the body through contaminated food or drink. Symptoms include nausea, vomiting, and diarrhea. Food poisoning causes similar symptoms.

Flu or pneumonia?

Pneumonia can be bacterial or viral. The symptoms can resemble those of flu, but an individual may have a sharp, stabbing pain in the chest, especially when they breathe deeply or cough.

Bacterial pneumonia can start slowly or suddenly. Symptoms can include:

  • a very high temperature
  • sweating
  • rapid breathing and pulse rate
  • blue nailbeds due to a lack of oxygen

Symptoms of viral pneumonia are similar to those of the flu. They include:

  • fever
  • dry cough
  • headache
  • aches and weakness

However, unlike the flu, symptoms of pneumonia usually develop gradually. Anyone who has a high fever and breathing difficulties should see a doctor immediately.

When is flu season?

People can have the flu at any time, but it is more common during the flu season. The timing and duration of the flu season change from year to year, but it usually happens around fall and winter.

Flu activity often starts to increase in October, and it can last as late as May. However, it is most common from December to February.

Prevention

The flu shot can help prevent flu, but it is not 100% effective. People should follow lifestyle measures to reduce their risk.

Lifestyle tips for avoiding flu

Tips for avoiding infection include:

  • practicing good hygiene, including frequent hand washing
  • keeping the immune system strong by following a healthful diet
  • quitting or avoiding smoking, as smokers are more likely to develop complications
  • staying away from people who have the flu

People should also stay away from others when they have the flu to avoid spreading it themselves.

Contagiousness

The flu virus transmits through droplets of liquid. A person can pass the virus on to another person who is up to 6 feet away from them when they cough, sneeze, talk, or breathe.

A healthy individual can pass on the virus a day before they, themselves, have symptoms. In other words, it is possible to pass on the flu before you know you have it. The infected individual can continue to transmit the virus for up to 5–7 days after symptoms appear.

People with a weakened immune system, older people, and young children may be able to pass on the virus for longer than this.

Flu is most contagious in the first 3–4 days after symptoms appear.

Transmission

A person can develop flu symptoms if droplets that contain the virus and come from the breath of another person enter their mouth, nose, or lungs.

This transmission can happen if:

  • Someone without the virus is near a person with flu.
  • Someone who is virus free handles an object a person with the virus has touched and then touches their mouth, nose, or eyes.

Research shows that just breathing can spread the flu virus. 

Incubation period

The incubation period of a disease is the time it takes from when the virus infects a person to when the symptoms start.

For flu, this is around 2 days, but it can vary from 1 to 4 days.

A person can transmit the virus even before symptoms appear.

Flu when pregnant

Flu can be more serious during pregnancy, as pregnancy affects how the immune system works. If a woman is pregnant and has flu, they may need to spend time in the hospital.

Pregnancy-related complications include a higher risk of:

  • preterm birth
  • low birth weight
  • stillbirth

Flu can be fatal for newborns. Risks to the mother include a greater chance of having complications, such as bronchitis, ear and blood infections.

How long does it last?

Flu symptoms appear suddenly, usually around 2 days after infection. Most symptoms disappear after about 1 week, but a cough may last for up to 2 weeks.

In some cases, a person may still be contagious for up to 1 week after their symptoms have disappeared.

If complications develop, these can take longer to resolve. Some of the more severe types of complications can have a long term impact on a person’s health, for example, kidney failure.

Some people experience post-viral fatigue for a week or so after the main symptoms disappear. They may have a lingering sense of tiredness and feeling unwell.

Timeline

Typically, flu may progress as follows:

  • The virus infects a person, usually through their nose or mouth.
  • After one day, they may be able to transmit the virus to others.
  • Symptoms appear 1–2 days after infection.
  • The chance of transmitting the virus is highest 3–4 days after symptoms appear.
  • After 4 days, the fever and muscle aches improve.
  • After 1 week, most symptoms disappear.
  • The risk of transmitting the virus disappears 5–7 days after symptoms appear.
  • The cough and tiredness may remain for a further week.

Precautions

The flu is not usually serious, but it is unpleasant. For some people, however, complications can arise. Some of these can be life threatening.

Complications include:

  • bacterial pneumonia
  • dehydration
  • worsening of chronic medical conditions, such as congestive heart failure, asthma, or diabetes
  • sinus problems and ear infections

The risk of experiencing severe symptoms and flu complications is higher in the following cases:

  • adults over 65 years of age
  • babies or young children
  • pregnant women
  • people with heart or cardiovascular disease
  • individuals with chest problems, such as asthma or bronchitis
  • people with kidney disease or diabetes
  • individuals who are taking steroids
  • people undergoing treatment for cancer
  • anyone with a weakened immune system

Flu shot

The single best way to prevent flu is to have a flu vaccination every year.

There are two types of vaccination:

The flu shot: A healthcare professional will administer the flu shot with a needle, usually in the arm. It is suitable for anyone older than 6 months, including healthy people and those with chronic medical conditions.

The nasal-spray flu vaccine: The nasal-spray flu vaccine contains live, weakened flu viruses that do not cause illness.

Seasonal flu shot

A flu shot will contain the vaccine for several influenza viruses, according to the CDC.

Examples include:

  • influenza A (H1N1) virus
  • influenza (H3N2) virus
  • one or two influenza B viruses

However, viruses adapt and change over time, and scientists may need to adjust the content of the vaccines each year.

Data from international surveillance programs help experts predict which types are likely to circulate in a given flu season. Protection begins about 2 weeks after receiving the vaccination.

Seasonal flu vaccinations should start in September or as soon as the vaccine is ready. They continue throughout the flu season, into January and beyond.

Flu shot side effects

The CDC note that the flu vaccine has a good safety record, and it cannot cause flu.

A person may experience the following adverse effects after having a vaccine, but these will be mild and usually pass within a few days.

  • pain, redness, and swelling at the injection site
  • headache
  • fever
  • nausea
  • muscle aches

Around 1–2 people in every 1 million may develop a condition known as Guillain-Barr syndrome (GBS). However, people can also develop GBS after having flu, and the risk of this is higher than with the vaccine. The risk of developing GBS may be lower with the nasal spray version of the vaccine.

If someone experiences hives, swelling, and difficulty breathing after any vaccine, they should seek immediate medical help as these may be the sign of an allergic reaction. A severe reaction is known as anaphylaxis, which can be life threatening.

People who have previously had an allergic reaction to a vaccine should not have the flu shot.

Flu shot pregnancy

It is safe to have the flu shot during pregnancy, and doctors recommend it. It takes about 2 weeks to provide protection. The vaccine will also pass through to the fetus and give them some protection from the flu.

Newborns cannot have a flu vaccine, but having flu can be dangerous for them. Having the vaccine can benefit both the mother and her unborn child.

Flu shot effectiveness

The flu shot cannot offer 100% protection from the flu as scientists cannot predict precisely what flu types will circulate during a season.

CDC figures from 2018–2019 show that the effectiveness of the vaccine in preventing influenza A or B was about 47%.

Many factors can contribute to the effectiveness of the flu shot from year to year. These can include the age and overall health of the person receiving the vaccination, plus how well the vaccine matches the prevalent viruses.

Flu shot for seniors

The CDC recommend a flu shot for people aged 65 years or more. As people get older, they are more likely to develop complications if they have flu.

Older people may need a higher dose of vaccine, as their immune systems may be less able to resist the flu virus. The vaccine cannot provide complete protection but will reduce the risk of flu and the severity of complications.

A 2017 study looked at data for older people in hospital with the flu during the flu season 2013–2014 in the U.S. Among those who had received the vaccine, there were lower rates of fatality, fewer complications, and less overall time spent in an intensive care unit.

People who are 65 years of age or older should ask their doctor about the vaccine at the start of each flu season. The doctor will recommend a vaccine that suits the individual.

Flu shot cost

The cost of a flu shot in the private sector is around $15–$24, depending on the type.

People should check their insurance policies to find out their cover. Medicare part B, for example, provide for one flu shot every flu season.

When to see a doctor

A doctor only needs to know that a person has the flu if:

  • they are already frail or have an existing health condition
  • they have a weakened immune system
  • they are infants or aged 65 years or over
  • their temperature remains high after 4–5 days
  • symptoms worsen or are severe
  • they become short of breath, develop chest pain, or both

However, anyone who has concerns about their symptoms should speak to their doctor for further advice.

What to know about endometriosis


Endometriosis is an incurable but manageable gynecological condition.

It occurs when endometrial implants, comprised of tissue normally found within the uterus, are present in other areas of the body.

As the tissue continues to thicken, break down, respond to menstrual cycle hormones, and bleed during the menstrual cycle, endometriosis forms deep inside the body.

Scar tissue and adhesions form, and this can cause organ fusion and anatomical changes.

Endometriosis is thought to affect around 11 percent of women in the United States aged between 15 and 44 years.

Fast facts on endometriosis

Here are some key points about endometriosis. More information is in the main article.

  • Endometriosis affects between 6 and 10 percent of women of reproductive age worldwide.
  • The condition appears to be present in a developing fetus, but estrogen levels during puberty are thought to trigger the symptoms.
  • Symptoms are generally present during the reproductive years.
  • Most women go undiagnosed, and in the U.S. it can take around 10 years to receive a diagnosis.
  • Allergies, asthma, chemical sensitivities, autoimmune diseases, chronic fatigue syndrome, fibromyalgia, breast cancer, and ovarian cancer are linked to women and families with endometriosis.

What is endometriosis?

Endometrial tissue consists of gland, blood cells, and connective tissue. It normally grows in the uterus, to prepare the lining of the womb for ovulation.

Endometrial implants are buildups of endometrial tissue that grow in locations outside the uterus.

When they grow outside the uterus, this is called endometriosis.

They can develop anywhere in the body, but they usually occur in the pelvic area.

They may affect:

  • the ovaries
  • the fallopian tubes
  • the peritoneum
  • the lymph nodes

Normally, this tissue is expelled during menstruation, but displaced tissue cannot do this.

This leads to physical symptoms, such as pain. As the lesions grow larger, they can affect bodily functions. For example, the fallopian tubes may be blocked.

The pain and other symptoms can affect different areas of life, including the ability to work, medical care costs, and difficulty maintaining relationships.

Symptoms

Other medical conditions such as pelvic inflammatory disease (PID), ovarian cysts, and irritable bowel syndrome (IBS) can mimic the symptoms of endometriosis.

Symptoms of endometriosis include:

  • Severe menstrual cramps, unrelieved with NSAIDS
  • Long-term lower-back and pelvic pain
  • Periods lasting longer than 7 days
  • Heavy menstrual bleeding where the pad or tampon needs changing every 1 to 2 hours
  • Bowel and urinary problems including pain, diarrhea, constipation, and bloating
  • Bloody stool or urine
  • Nausea and vomiting
  • Fatigue
  • Pain during intercourse
  • Spotting or bleeding between periods

Pain is the most common indication of endometriosis, but the severity of the pain does not always correlate with the extent of the disease.

Pain often resolves following menopause, when the body stops producing estrogen production. However, if hormone therapy is used during menopause, symptoms may persist.

Pregnancy may provide temporary relief from symptoms.

Complications

Complications include:

  • infertility, which can affect 50 percent of those with the condition.
  • increased risk of developing ovarian cancer or endometriosis-associated adenocarcinoma
  • ovarian cysts
  • inflammation
  • scar tissue and adhesion development
  • intestinal and bladder complications

It is important to see a health care provider about symptoms, to avoid future complications.

Treatment

Surgery is possible, but it is normally considered only if other treatments are not effective.

Other options include:

Pain medications: Either over-the-counter (OTC) nonsteroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen (Advil, Motrin IB, others) or prescription drugs for the treatment of painful menses.

Hormones: Treatment may be with hormonal therapies such as hormonal birth control, Gonadotropin-releasing hormone (Gn-RH) agonists and antagonists, Medroxyprogesterone (Depo-Provera) or Danazol. Placement of an intrauterine device (IUD) may also be recommended.

Surgery: Initial surgery will seek to remove the areas of endometriosis, but a hysterectomy with removal of both ovaries may be necessary.

Fertility treatment: Pregnancy may be recommended via in-vitro fertilization (IVF).

Managing symptoms at home

Complementary and alternative treatments may include acupuncture, chiropractic, and herbal medicine, but there is little evidence to show that these are effective.

Avoiding caffeine may help to reduce pain, as caffeine can worsen symptoms.

Exercise, such as walking, may reduce pain and slow the progress of the condition by reducing estrogen levels.

It is important to monitor symptoms, because of the long-term complications of endometriosis. Intolerable pain or unexpected bleeding should be reported to a doctor.

Although there is currently no cure for endometriosis, most women are able to relieve the pain of symptoms and will still be able to have children.

Diagnosis

Diagnosis can be challenging because there is no single test for evaluation.

The only way to truly confirm the condition is by undergoing a surgical laparoscopy.

A surgical laparoscopy is a minimally invasive procedure in which a thin, lighted tube with a miniature camera attached, called a laparoscope, is inserted through a small incision in the pelvic area.

A diagnosis can be categorized as follows:

  • Stage 1: Lesions are minimal and isolated
  • Stage 2: Lesions are mild. There may be several and adhesions are possible.
  • Stage 3: Lesions are moderate, deep or superficial with clear adhesions
  • Stage 4: Lesions are multiple and severe, both superficial and deep, with prominent adhesions.

It can take many years to receive a diagnosis.

Other possible diagnostic strategies include a pelvic exam, radiologic imaging with ultrasound or magnetic resonance imaging (MRI), and the use of certain medications including birth control or gonadotropin releasing hormone (GnRH) agonists.

Diet

Dietary steps have been suggested for managing the pain and effects of endometriosis.

A 2004 study suggests that a brown seaweed called bladderwrack may have an estrogen-reducing effect in women. This can reduce the growth rate of endometriosis.

One author presented a case study using a diet low in short-chain-fermentable carbohydrates to reduce the symptoms of endometriosis. This diet has been shown to work on IBS and since it is often found with endometriosis, then perhaps the diet would be effective for those with only endometriosis.

More research is needed, but there is little harm in trying this approach.

Dietary choices have also been linked to the development of endometriosis. A study carried out in 2011 suggested that fruit intake increased the risk of endometriosis and a higher total fat intake decreased the risk.

Dairy products were also shown to reduce the risk of endometriosis, although these results were not statistically significant.

Eating yogurt, sauerkraut, and pickles or finding a good source of probiotics may help reduce gastrointestinal symptoms and cause increased digestive activity.

Avoiding caffeine may help to reduce pain, as caffeine can worsen symptoms.


All about dementia, Medical Myths 

Today, an estimated 5.8 million people aged 65 years or older in the United States have dementia. Due to the fact that the average lifespan of people in the U.S. has increased over recent decades, some experts project that by 2050, the number of older adults with dementia could reach 13.8 million.

1. Dementia is inevitable with age

This statement is not true. Dementia is not a normal part of aging.

According to a report that the Alzheimer’s Association published, Alzheimer’s disease, which is the most common form of dementia, affects 3% of people aged 65–74 years in the U.S. As a result of the risk increasing as we age, 17% of people aged 75–84 years and 32% of people aged 85 years and older have a dementia diagnosis.

2. Dementia and Alzheimer’s disease are the same thing

This is not quite correct. Alzheimer’s is a type of dementia, accounting for 60–80% of all dementia cases. Other types of dementia include frontotemporal dementia (FTD), vascular dementia, mixed dementia, and Lewy body dementia.

The National Institute on Aging define dementia as “the loss of cognitive functioning — thinking, remembering, and reasoning — and behavioral abilities to such an extent that it interferes with a person’s daily life and activities.”

Although dementias share certain characteristics, each type has a distinct underlying pathology.

Alzheimer’s disease is associated with a buildup of so-called plaques and tangles in the brain. These structures interfere with brain cells, eventually killing them. In contrast, brain cell death in vascular dementia occurs due to a lack of oxygen, which can result from a stroke, for instance.

FTD, as another example, occurs when abnormal protein structures form in the frontal and temporal lobes of the brain, causing the brain cells in these regions to die.

3. A family member has dementia, so I will get it

A common myth is that dementia is purely genetic. In other words, if a person’s family member has a dementia diagnosis, they are guaranteed to develop dementia later in life. This is not true.

Although there is a genetic component to some forms of dementia, the majority of cases do not have a strong genetic link.

As we learned above, rather than genetic factors, the most significant risk factor for dementia is age. However, if a parent or grandparent developed Alzheimer’s when they were younger than 65 years, the chance of it passing on genetically is higher.

Early-onset Alzheimer’s is relatively uncommon, though. It occurs in about 5.5% of all Alzheimer’s cases.

As the majority of dementia cases are Alzheimer’s disease, this means that most dementia cases are not hereditary. FTD, which is much less common, has a stronger genetic link, but if a parent or grandparent develops the condition, it does not mean that children or grandchildren are guaranteed to develop it.

Today, FTD affects an estimated 15–22 in every 100,000 people. Of these individuals, 10–15% have a strong family history of the condition.

4. Dementia only affects older adults

Age is a risk factor for dementia, but dementia can affect younger adults in rare cases. Some scientists estimate that, in people aged 30–64 years, 38–260 people in 100,000 — equivalent to 0.038–0.26% — develop early-onset dementia.

In the 55–64 age bracket, this increases to close to 420 people in 100,000, or 0.4%.

5. Using aluminum pans causes Alzheimer’s

In the 1960s, scientists injected rabbits with high levels of aluminum. They found that the animals developed neurological lesions similar to those that form in the brains of people with Alzheimer’s.

Additionally, some studies have identified aluminum within the plaques associated with Alzheimer’s. However, aluminum also appears in the healthy brain, and researchers have not established a causal link between this element and the disease.

Following on from these studies, myths still circulate that drinking from aluminum cans or cooking with aluminum pots increases the risk of Alzheimer’s.

However, since those early experiments, scientists have not found a clear association between Alzheimer’s and using aluminum pots and pans.

Although researchers will, eventually, establish the precise relationship between aluminum and Alzheimer’s, consuming aluminum through the diet is unlikely to play a major role.

As the Alzheimer’s Society explain: “Aluminum in food and drink is in a form that is not easily absorbed into the body. Hence, the amount taken up is less than 1% of the amount present in food and drink. Most of the aluminum taken into the body is cleaned out by the kidneys.”

However, they also write that some research has found “a potential role for high dose aluminum in drinking water in progressing Alzheimer’s disease for people who already have the disease.”

6. Dementia signals the end of a meaningful life

Thankfully, this is not the case. Many people with a dementia diagnosis lead active, meaningful lives. Some people fear that if a doctor diagnoses them with dementia, they will no longer be able to go for a walk alone and will have to stop driving their vehicle immediately.

It is true that these adjustments may come in time as the condition progresses, but in mild cases of dementia, no changes may be necessary. As dementia worsens, changes to the way an individual leads their life are likely, but that does not mean that the person cannot lead a fulfilling life.

“Too many people are in the dark about dementia — many feel that a dementia diagnosis means someone is immediately incapable of living a normal life, while myths and misunderstandings continue to contribute to the stigma and isolation that many people will feel,” explains Jeremy Hughes, former Chief Executive of the Alzheimer’s Society.

7. Memory loss always signifies dementia

Although memory loss can be an early symptom of dementia, it does not necessarily signify the start of this condition. Human memory can be unpredictable, and we all forget things occasionally. However, if memory loss is interfering with everyday life, it is best to speak with a doctor.

Although memory issues tend to be an early sign of Alzheimer’s disease, that is not the case for other forms of dementia. For instance, early signs and symptoms of FTD can include changes in mood and personality, language difficulties, and obsessive behavior.

8. Dementia is always preventable

This, unfortunately, is untrue. Importantly, though, certain factors can either reduce the risk of certain types of dementia developing or delay their onset.

For instance, the Lancet Commission’s 2020 report on dementia prevention, intervention, and care lists 12 factors that increase the risk of dementia:

  • less education
  • hypertension
  • hearing impairment
  • smoking
  • obesity
  • depression
  • physical inactivity
  • diabetes
  • low levels of social contact
  • alcohol consumption
  • traumatic brain injury
  • air pollution

Some of these factors are more difficult to modify than others, but working on changing any of them might help reduce the risk of developing dementia. The authors of the report explain:

9. Vitamins and supplements can prevent dementia

Linked to the section above, this is also false. To date, there is no strong evidence that any vitamin or mineral supplements can reduce the risk of dementia. In 2018, the Cochrane Library conducted a review with the aim of answering this question.

Their analysis included data from more than 83,000 participants across the 28 included studies. Although the authors report “some general limitations of the evidence,” they conclude:

10. All people with dementia become aggressive

In some cases, people with dementia might find it increasingly hard to make sense of the world around them. This confusion can be frustrating, and some individuals might respond to the emotions in an angry manner. However, this is not the case for everyone.

In a study involving 215 people with dementia, 41% of the participants developed aggression during the 2-year study. When they looked at factors that increased the risk of developing aggression, the researchers identified two of the primary factors as physical pain and a low quality relationship between the person and their caregiver.

11. Dementia is never fatal

Unfortunately, dementia can be fatal. According to a recent study, which appears in JAMA Neurology, dementia may be a more common cause of death than experts have traditionally thought it to be. The authors “found that approximately 13.6% of deaths were attributable to dementia over the period 2000–2009.”

Dementia worries people, especially as they age, and this is justifiable in many ways. However, it is important to counter misinformation that might enhance concerns and stigma.

For now, researchers are working tirelessly to develop better ways to treat and prevent dementia. In the future, hopefully, science will reduce the impact of dementia and, therefore, the fear associated with the condition.

Water: Do we really need 8 glasses a day?


We often hear that we should drink eight 8-ounce glasses of water a day. However, there is some controversy about this figure and what it really means.

Water is an essential nutrient. It is necessary to sustain all forms of life, and humans can only live a few days without it. It is also a healthful drink.

Health authorities and others often encourage people to consume 2 or more liters of water a day, but is this only plain water or does water from other sources count?

Some sources have described these recommendations as a “myth,” and professionals have questioned the guidelines.

Some point to a lack of scientific evidence to support the claims, while others note that promoters of the concept have included a major mineral water producer.

How much plain water do we really need?

Fast facts on water intake

Here are some key points about daily water consumption.

  • Foods and fluids, including water, are the main source of water in our bodies.
  • The advice to drink eight 8-ounce glasses of water a day is not based on evidence.
  • The amount of water we need depends on individual needs and circumstances, including activity and climate.
  • The healthy body naturally maintains a well-tuned balance of fluid, and the thirst mechanism tells us when we need more.

Recommended daily water intake

In 1945, the U.S. Food and Nutrition Board advised people to consume 2.5 liters (84.5 fluid ounces (fl oz) of water a day, including fluid from prepared foods.

Today, the Centers for Disease Control and Prevention (CDC) say, “There is no recommendation for how much plain water adults and youth should drink daily.” However, there are recommendations about total fluid intake from all sources.

In 2004, the Institute of Medicine set the amount at around 2.7 liters, or 91 fluid ounces (fl oz) of total water a day for women and an average of around 3.7 liters (125 fl oz) daily for men.

This refers to the total daily fluid intake from all sources, defined as “the amount of water consumed from foods, plain drinking water, and other beverages.”

The U.S. Dietary Guidelines 2015-2020 do not recommend a specific daily water or fluid intake, but they do recommend choosing plain rather than flavored water and juices with added sugar.

There is currently no set upper level for water intake, although excessive quantities have been known to have adverse effects.

In the United Kingdom, the National Health Service (NHS) recommend consuming 6 to 8 glasses a day, or 1.9 liters (almost 34 fl0.oz), including water that is in food. They note this amount is suitable for a temperate climate. In hotter climates, they say, more will be needed.

Recommended intake by age

There is no fixed amount of fluid recommended by age, but some patterns emerge among healthy individuals doing a moderate amount of activity in a temperate climate.

The following shows average water intake for infants and adults:

Age group Average daily fluid intake
Infants From 525 ml for a 3.5-kilo newborn to 1,200 ml for an 8-kilo infant per day, as breast or bottled milk
Adults aged 19 to 30 years Average of 3.7 liters a day for men and 2.7 liters for women, depending on climate, activity, pregnancy status, and health

Infants

The amount of formula or breast milk an infant takes in averages 780 milliliters (ml), or just over 26 fl oz, of breast milk or formula milk each day until the age of around 6 months. Before the age of 6 months, plain water is not recommended.

This ranges from around 525 ml (just under 18 fl oz) a day for 3.5-kilo newborn to 1,200 ml per day (45 fl oz) for an 8-kilo infant at 6 months, or around 150 ml (5 fl oz) per kilo of weight per day.

This is proportionally far more than an adult needs. After infants start consuming solid foods, they need less fluid from breast milk and formula.

Children aged over 12 months

Children should be encouraged to drink water:

  • as part of the daily routine, for example, after brushing teeth and before, during and after playtime at school
  • when the weather is warm
  • as an alternative to sweetened drinks and juices

Juice consumption should be limited to one glass a day.

Parents are advised to keep a pitcher handy to encourage healthful water-drinking habits, and schools should have water fountains or equivalent facilities.

Children who are sick with a fever

For children who are at risk of dehyration, for example, with a fever, the CDC recommend the following:

Age Amount of fluid needed
Up to 12 months 3 cups
1 to 3 years 4 cups
4 to 8 years 5 cups
6 to 13 years 8 cups
14 years and over 11 to 13 cups for males and 8 to 9 cups for females

If a child is sick with a fever, it is important to seek medical help. A doctor may also advise oral an rehydration solution to ensure an adequate electrolyte balance.

Adults aged 19 to 30 years

The CDC cites figures showing that in 2005-2010 in the U.S., young people were drinking an average of 0.45 liters or 15 fl oz of water on a given day, while adults drank an average of 1.2 liters, or 39 fl oz.

The adequate intakes recommended for total water from all sources each day for most adults between 19 and 30 years of age are:

  • 3.7 liters (or about 130 fl oz) for men
  • 2.7 liters (about 95 fl oz) for women

One source suggests a man’s requirements might range from 2.5 liters (84.5 fl oz) if sedentary to up to 6 liters (203 fl oz) if active and living in a warm climate.

For women, the requirements will probably be 0.5 to 1 liter (17 to 34 fl oz) lower than those for men because of typically smaller body mass.

However, during pregnancy, women are likely to need an extra 0.3 liters (10 fl oz), and an additional 0.7 to 1.1 liters (23 to 37 fl oz) while breast-feeding.

Older adults

Older adults may be at risk of both dehydration and overhydration, as a result of health conditions, medications, loss of muscle mass, reduction in kidney function, and other factors.

Older adults who are well hydrated have been found to have:

  • fewer falls
  • less constipation
  • in men, a lower risk of bladder cancer

Dehydration has been linked to a higher frequency of:

  • urinary tract infections
  • confusion
  • kidney failure
  • slower wound healing

Needs for fluid intake will depend on the individual.

Few studies have looked at fluid input and output in older people, but at least one has concluded that it is not significantly different from that of younger people.

Those caring for older people are encouraged to provide fluids regularly and assist with ambulation, especially if a reduction in mobility makes it harder to visit the bathroom.

Where do the figures come from?

While water is known to be crucial for life and for preventing dehydration, recommendations for intake are based mainly on survey results showing the average amounts that people consume.

Conclusions are based on the assumption that these amounts must be about right for optimal hydration.

There is little evidence showing that specific quantities have a particular effect on health.

It is impossible to define an optimal intake, because these vary greatly according to:

  • activity
  • environmental conditions
  • individual factors
  • body mass
  • sex and age
  • health status, for example, poor kidney function
  • medications, such as diuretics
  • whether or not a person is pregnant or breast-feeding

Recommendations that a person should drink eight glasses of water a day also fail to take into account the fact that much of our fluid intake comes from food and other drinks.

Sources of water

Water in the body comes not only from drinking water.

Estimations vary, but according to one source:

  • around 20 to 30 percent comes from food
  • some 60 to 70 percent comes from drinking water and other fluids
  • a small percentage, about 10 percent is “metabolic water,” produced by cells during normal cell function

The more active the body is, the more metabolic water is produced.

Some surveys suggest that around 20 percent of water intake comes from foodstuffs and the rest is from fluids. This depends on diet. A higher intake of fresh fruit and vegetables will mean a higher intake of water from foods.

Metabolic water accounts for around 250 to 350 ml (8.4 to 11.8 fl oz) a day.

Water content of foods

Here are some examples of the water content of different foods and fluids:

Water content as a percentage (%) Food or drink
100% Water
90-99% Fat-free milk, tea, coffee, juicy fruits such as strawberries and cantaloupes, vegetables such as lettuce, celery, and spinach
80-89% Fruit juice, yogurt, fruits such as apples, pears and oranges, vegetables such as carrots, and cooked broccoli
70-79% Bananas, avocados, baked potatoes, cottage and ricotta cheeses
60-69% Pasta, beans, and peas, fish such as salmon, chicken breasts, and ice cream
30-39% Bread, bagels, and cheddar cheese
1-9% Nuts, chocolate cookies, crackers, cereals
0% Oils and sugars

Tap or bottled water?

Bottled or tap water are equally effective at hydrating the body. In terms of hydration, studies in the UK have not found any significant difference between drinking the two.

Mineral waters contain different amounts of minerals, depending on where they come from, but this, too is not significant, as most minerals come from other dietary sources.

What about coffee?

Caffeinated drinks are thought to be dehydrating as opposed to hydrating because of a belief that they have a diuretic effect on our water balance.

A number of studies to test how caffeinated fluids affect hydration have shown that tea and coffee are in fact good sources of water and do not lead to dehydration.

One study of 18 healthy male adults found that no significant difference in impact on hydration, measured in body weight, urine and blood tests after a variety of caffeinated, non-caffeinated, caloric, and non-caloric drinks.

“Advising people to disregard caffeinated beverages as part of the daily fluid intake is not substantiated,” say the researchers.

Another concludes that there is “no evidence of dehydration with moderate daily coffee intake.”

Benefits of drinking water

Water is necessary for the body. It:

  • regulates temperature
  • lubricates the joints and bones
  • protects the spinal cord and other sensitive tissues
  • removes waste from the body

Short-term benefits

A healthy fluid intake, including water, prevents dehydration.

The short-term symptoms of significant dehydration include:

  • unclear thinking
  • mood change
  • overheating
  • feeling thirsty and having a dry mouth
  • fatigue
  • dizziness
  • headache
  • dry mouth, eyes, and lips
  • urinating less than usual

Overheating can lead to organ damage, coma, and death.

The CDC urge people to make sure they drink enough water before, during, and after physical work, especially if this involves activity in a hot climate. This can help maintain alertness and effectiveness.

In a hot environment, you may need one 8-ounce cup every 15-20 minutes, but not more than 48 ounces in one hour, as this can lead to hyponatremia, a low level of sodium.

Plain water provides hydration without adding calories or jeopardizing dental health. Sports drinks can be useful in moderation, but too many will add unnecessary sugar to the body.

Long-term benefits

Studies suggest that long-term benefits of drinking water might include a lower risk of:

  • colorectal cancer and cancers of the urinary system
  • heart disease
  • urinary tract infections
  • kidney stones
  • constipation
  • high blood pressure
  • stroke

However, these possible long-term benefits also depend on a wide variety of other factors.

In addition, study participants with the lower risk of these conditions still drank fewer than eight 8-ounce glasses of water a day.

Weight loss

Drinking water may also help with weight loss, if a person “preloads” with water before a meal. This may help them feel fuller faster during meals. If they choose water over sweetened juice or soda, they consume fewer calories.

In a study where 318 people with obesity or overweight switched from sugary drinks to plain water, an average loss of 2 to 2.5 percent in weight was noted. But this could be easily explained by a decrease in total calories rather than water itself.

Other possible benefits

Other supposed benefits of drinking more water include prevention of:

  • migraine
  • nosebleeds
  • depression
  • high blood pressure
  • asthma
  • dry cough
  • dry skin
  • acne

However, there is little or no scientific evidence to confirm these claims.

In children, a higher water consumption has been linked to better diets, behavior and overall health.

When is more water needed?

Extra water may be needed when a person:

  • is in a hot climate
  • is doing physical activity
  • has diarrhea or vomiting
  • has a fever

These can lead to additional loss of water.

What about a water detox?

There have also been claims that water can “detox” the body.

These claims are not based on scientific facts.

The liver, kidneys, and human body normally break down toxic substances into less harmful ones or expel them from the body through urine. Water does not have a unique role in these processes.

Too much water can lead to hyponatremia, also known as low sodium. Low sodium levels can be life-threatening causing confusion, seizures, coma and death.

Hydration during exercise

During exercise, factors affecting the amount of fluid lost and the need for extra intake include:

  • the type and intensity of the activity
  • environmental factors, such as climate
  • the size and muscle mass of the athlete

Guidance from the American College of Sports Medicine (ACSM), published in 2007, recommends making an individual estimation of the fluid replacement needed by people taking part in exercise, to avoid dehydration.

Larger athletes may require higher fluid intake, for example, compared with smaller, leaner athletes, due to a larger body surface and higher body weight.

The ACSM advises drinking water during activity to prevent:

  • dehydration that leads to a fall in body weight of more than 2 percent
  • changes in the electrolyte balance

These changes, they say, can lead to reduced performance.

However, a study published in the British Journal of Sports Medicine concludes that a loss of up to 3 percent of water has “no effect” on real-world sports performance.

The conclusions were supported by findings from a cycling time-trial over 25 kilometers in hot conditions of 91.4° Fahrenheit and 40 percent relative humidity.

Results showed no difference in performance, physiological, and perceptual variables between participants who received hydration and those who did not.

The reason for this, say the authors, is “the body’s rapid defense of its plasma and blood volume following dehydration.”

In other words, the body can regulate water balance with high sensitivity.

Authors of a study focusing on runners in the 2002 Boston Marathon, published in the New England Journal of Medicine (NEJM), concluded:

“Because runners vary considerably in size and in rates of perspiration, general recommendations regarding specific volumes of fluids and frequencies of intake are probably unsafe and have been superseded by recommendations favoring thirst or individual perspiration rates as a primary guide.”

A review of 15 studies found that exercise-induced dehydration did not reduce performance. The authors encouraged athletes to “drink according to their thirst.”

Water and dehydration in the human body

Dehydration can be measured in terms of blood and urine osmolality.

Osmolality is an estimation of the osmolar concentration of plasma. It reflects the concentration of particles in a solution.

As regards dehydration:

  • high osmolality indicates a greater need for hydration
  • low osmolality suggests there are too few particles, specifically sodium and electrolytes, a sign of overhydration

How much water is in the human body?

The main chemical making up the human body is water. It accounts for between 55 percent and 75 percent of the body’s composition, and it varies between individuals.

  • in the average young man, between 50 and 70 percent of the body weight is water
  • in infants, 75 percent of body weight is water
  • in older people, it is 55 percent

Differences of age, sex, and aerobic fitness affect an individual’s ratio of lean to fat body mass and therefore how much water they contain.

Calculating human water needs

The amount of water we need to take in to maintain a healthy balance is decided by how much water we use and lose that must be replaced.

Over the course of 24 hours, healthy resting adults regulate their water balance to within around 0.2 percent of body weight.

In older children and adults, if a person’s body weight falls by 3 percent due to fluid loss, this is considered dehydration. Moderate dehydration is when weight falls by 6 percent, and severe dehydration is when it falls by 9 percent.

It is difficult to measure the amount of water used or lost by the body. Measures taken across groups of people in studies have shown wide variation.

However, if people show symptoms of dehydration, such as confusion or decreased urine output, they need medical attention.

What about dark urine?

There is a popular concept that darker urine means a person is dehydrated, while pale urine shows they are adequately hydrated.

However, it is difficult to assess the significance of urine color precisely. It depends on the time of day, medications, and other health problems.

Tea- or cola-colored urine, particularly after exercise, can indicate serious muscle injury and severe dehydration and requires urgent medical attention.

However, in normal circumstances, urine that is well within the limits of normal osmolality in laboratory tests can appear moderately yellow. This does not indicate that a person is dehydrated.

In addition, other factors such as diet, medications and health conditions can cause individuals to differ in their urine color.

How does the body regulate water?

Without water, there is no life. For this reason, all living organisms have adapted to avoid dehydration.

Humans can only survive for a few days without water. Infants and older people who lose water through illness and do not replace it can experience life-threatening complications.

Most of the time, however, our bodies’ sensitive natural mechanisms maintain appropriate fluid levels, or homeostasis, as long as we continue to consume food and water.

The two main ways the body does this are:

Thirst: This which tells us when we need to take in more fluid.

Urine output: The kidneys regulate any excess or lack of the water we consume by either emptying it into the urinary bladder or holding onto it in the blood plasma.

The body expels 0.5 to 1 liter (around 17 to 34 fl oz) per day in the form of urine.

The kidneys also:

  • regulate the balance of electrolytes, such as sodium and potassium, in the body fluids
  • receive hormonal signals to conserve or release water into the urine if the brain detects changes in the concentration of the solutes in the blood

The brain also responds to these changes in solutes, known as plasma osmolality. This is one factor that triggers the thirst for water.

Other ways in which water is lost or expelled from the body are:

Breathing: About 250-350 ml (8.5 to 11.8 fl oz) per day exit from the lungs during. exhalation

Feces: Around 100-200 ml (3.4 to 6.8 fl oz) per day passes out of the body in feces.

Sweating: Sedentary loss ranges from around 1,300-3,450 ml (44 to 117 fl oz) a day, but a physically active person can lose 1,550-6,730 ml (52 to 227.5 fl oz) a day

What about ‘8 by 8’?

It is often said that we needed to drink at least eight glasses of water a day, although there is little scientific evidence to support this.

Prof. Heinz Valtin, of Dartmouth Medical School in Hanover, NH, is one expert who has questioned this advice. He suggests it may be not only unnecessary but maybe even harmful.

In an article published in the American Journal of Physiology in 2002, he concludes:

“Not only is there no scientific evidence that we need to drink that much, but the [8 by 8] recommendation could be harmful, both in precipitating potentially dangerous hyponatremia and exposure to pollutants, and also in making many people feel guilty for not drinking enough.”

Prof. Heinz Valtin

The right types of fluid

Recommendations are now more likely to note that water can come from other beverages and from food. However, these should be chosen carefully.

Beverages that are high in fat or sugar or contain alcohol do not benefit health, and plain water is recommended in preference to these.

More than one alcoholic beverage per day in women and more than two alcoholic beverages per day in men on a regular basis can lead to liver inflammation and injury, an increased cancer risk, as well as negatively affecting every system of the body.

Fatty or sweetened drinks increase calories and lack nutritional value.

Processed foods, such as burgers and chips, high fat, and high sugar diets will contain less water than fresh fruits and vegetables.

Nearly all foods contain water, but fresh and healthful ingredients contain the most compared to processed foods, sugars, and fats.

The CDC note with concern that young people who consume high quantities of junk food are also drinking less water and eating less fresh fruit and vegetables. This can lead to further health problems. They are also often drinking highly sweetened beverages rather than water.

A study published by the CDC in 2013 showed that:

  • Seven percent of adults said they did not drink any water
  • Thirty-six percent said they drank 1 to 3 cups a day
  • Thirty-five percent reported drinking 4 to 7 cups
  • Twenty-two percent said they drank 8 cups or more

Those who drank the least water were also less likely to pursue other healthful behaviors, such as consuming fresh fruits and vegetables.

Too much water?

Some have raised concerns that consuming too much water could be dangerous.

Not only the amount of fluid in the body but the balance of minerals that is important for maintaining health and life.

Too much water in the body could lead to hyponatremia, or water intoxication, when sodium levels in the blood plasma become too low.

Symptoms include:

  • lung congestion
  • brain swelling
  • headache
  • fatigue and lethargy
  • confusion
  • vomiting
  • seizures
  • coma
  • death

Hyponatremia may be a risk for people who use the recreational drug Ecstasy. This is likely due to a variety of reasons including a change in hormone levels, brain chemistry, body function, kidney function, along with increased sweating and thirst.

People who drink too much water while exercising could also be at risk. In the Boston runners survey, for example, almost 2,000 of the participants were thought likely to have some degree of hyponatremia due to excessive fluid consumption, and 90 may have finished with critical hyponatremia.

Another risk factor is having certain diseases or using some medications. Diabetes, for example, can lead to excessive thirst. Conditions in which the kidneys cannot excrete enough water, too, can result in this type of problem.

However, just as the body can adapt to higher or lower levels of water and can remind us, through thirst, when we need to drink more, scientists believe an internal mechanism also stops most people from drinking too much water.

Takeaway

There are few scientific measures of how much water we need.

Most studies have focused on how much people consume and assumed that this figure matches or exceeds our needs. It does not determine whether a person is efficiently hydrated or not.

The amount of water a person uses and loses varies according to conditions and activities. Heat, activity, and illness, such as diarrhea and vomiting, can lead to dehydration.

Most healthy people in a temperate climate consume sufficient fluid to remain healthy while carrying out their daily activities, and around one fifth to a quarter of this comes from food. Where there is a lack, the body will usually regulate these needs.

Meanwhile, those who work outside or exercise in a hot climate will not be able to get all their water needs from food. They will need additional water.

Perhaps, as Prof. Farrell of Monash University says, “If we just do what our body tells us, we will probably get it right.”

Q:

Should people aim to consume a particular quantity of water each day?

A:

The most recent research supports the theory that thirst is the best guide for determining fluid intake. For the average individual, even in routine physical activity, allow thirst to determine when and how much you drink. 

Those with certain medical conditions, such as kidney disease or heart failure, may need to follow their doctor’s advice regarding daily fluid intake in order to avoid the complications of low sodium levels in their blood.

Judith Marcin, MD

Answers represent the opinions of our medical experts. All content is strictly informational and should not be considered medical advice.