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.

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.

A blackout is a loss of consciousness or complete or partial memory loss. Possible causes of blackouts include epilepsy and drinking a large volume of alcohol.

If a person notices someone falling unconscious, they should put them in a seated position or help them lie down so that they do not hurt themselves.

What is a blackout?

Some people define blackouts as a temporary loss of consciousness that typically lasts for a few minutes.

However, a 2016 review observes that overconsuming alcohol may lead to alcohol-induced blackouts, which can, in some cases, be due to memory loss rather than a loss of consciousness.

Other possible causes of blackouts include syncope, epilepsy, and stress.

Alcohol blackouts

Two different kinds of blackouts can result from drinking alcohol: en bloc and fragmentary.

When a person consumes a very large volume of alcohol, an en bloc blackout may occur. If this happens, they will not remember anything that they did while they were drinking.

Fragmentary blackouts tend to affect only patches of memory, so a person may be able to piece together a memory on prompting.

Symptoms

If someone has drunk too much alcohol, they may have the following symptoms of alcohol intoxication:

• becoming confused
• difficulty staying awake, or not being able to wake up
• clammy skin and low body temperature
• slow heart rate
• vomiting and seizures

Treatment

If a person is showing symptoms of severe alcohol intoxication, it is important to call the emergency services for treatment.

According to the National Institute on Alcohol Abuse and Alcoholism, a very high blood-alcohol concentration may result in a person struggling to remain conscious. In the most severe cases of alcohol intoxication, they may even fall into a coma. Due to this, it is really important to get someone emergency help if their condition is deteriorating.

In cases where someone who has drunk too much needs first aid, people should:

• lie the person down on their side with their knees up so that they will not choke on their vomit
• check that they are breathing every 15 minutes
• monitor their condition and call 911 immediately if it worsens

Syncope blackouts

The American Heart Association (AHA) describe a syncope blackout as a short temporary loss of consciousness that happens when not enough blood reaches the brain.

People may also refer to this type of blackout as fainting. Low blood pressure typically causes syncope blackouts because the heart cannot pump enough oxygen-rich blood to the brain.

There are two main types of syncope blackouts: neurally mediated and cardiac.

A neurally mediated syncope is usually benign and requires no further treatment. It could occur when a person’s blood pressure drops after they experience pain or dehydration or get up too quickly. This type of syncope tends to occur more in children and young adults.

A cardiac syncope is more serious as it could signal an underlying problem with the heart. Tachycardia, bradycardia, or other types of hypotension could cause a cardiac syncope. If a person does not get treatment, they are at risk of complications or even sudden cardiac death.

Treatment

A doctor may prescribe fludrocortisone to reduce blackouts in people who experience neurally mediated syncope.

If anyone feels as though they are about to faint, they should sit or lie down so that they do not injure themselves if they fall unconscious.

Diagnosis

If a person is experiencing syncope blackouts, a doctor may request an electrocardiogram (EKG) to see whether there are any underlying problems with the heart.

They may also order a tilt test. During this test, a person lies down on a board that moves to change their position while healthcare professionals measure their blood pressure and heart rate.

Epilepsy blackouts

A disturbance of neuronal activity in the brain can cause an epileptic episode. During these episodes, people may experience a seizure. Their muscles may contract, and they could lose consciousness.

However, just because a person has epilepsy, it does not necessarily mean that they will blackout when they have a seizure. The disorder is a spectrum, and it covers many other symptoms.

Symptoms

Many different symptoms could accompany epileptic blackouts, depending on the type of seizure that a person is experiencing.

According to the University of California, San Francisco, one particular type of epileptic seizure that causes blackouts is a tonic-clonic seizure — also known as a grand-mal seizure. During this epileptic episode, people lose consciousness, and the body goes stiff (tonic phase). The muscles then contract, which may result in the jaw clamping shut (clonic phase).

Treatment

The National Institute of Neurological Disorders and Stroke estimate that 70% of people with epilepsy can control their symptoms by taking medication or undergoing surgery.

Since the Food and Drug Administration (FDA) approved them in 2019, doctors have been able to prescribe cenobamate tablets for adults who experience blackouts during seizures. If medication proves ineffective, doctors may recommend surgery.

Some children may be unable to take medication due to the side effects. In these cases, they may benefit from special diets.

Diagnosis

If a doctor suspects that a person has epilepsy, they may request an MRI or CT scan. These imaging techniques help the doctor examine brain activity and rule out other neurological conditions.

Learn more about epilepsy here.

Can stress cause blackouts?

If a person experiences blackouts as a result of stress, this is known as a psychogenic blackout. While these blackouts are similar to syncope and epileptic blackouts, the causes are different.

Experts believe that when people are experiencing a threatening feeling, thought, or memory, it can overwhelm them so much that it induces a seizure.

Some symptoms of psychogenic blackouts include:

• fainting and falling
• jerking movements of the arms and legs
• losing control of the bladder and bowel
• going “blank” and feeling out of touch with the surroundings
• not being able to remember the blackout

Treatment

According to the Epilepsy Society, people who experience psychogenic blackouts may benefit from cognitive behavioral therapy (CBT). CBT helps people identify stressful triggers and put techniques in place to cope when they feel overwhelmed.

Diagnosis

If a person believes that they are experiencing psychogenic blackouts, a doctor may refer them to a neurologist, who may be able to diagnose psychogenic blackouts by ruling out other causes.

Can medication cause blackouts?

According to one 2015 study, vasodilatory medications and diuretics could result in syncope blackouts.

Another 2015 study suggests that overconsuming sedatives could cause memory loss. In one case study, the excessive use of alprazolam (Xanax) led a 50-year-old woman to experience memory loss blackouts. However, more research is necessary to support these findings.

When to see a doctor

A person should speak to a doctor if they believe that they are experiencing symptoms of syncope, epileptic blackouts, or blackouts that are the result of medication. In cases of severe alcohol intoxication, a person may need emergency assistance.

With treatment, most people will be able to continue their daily activities. If a person’s blackouts are related to an underlying medical condition, they should stop once the person receives treatment to manage the condition.

Summary

Excessive alcohol use, stress, medication, and epilepsy can all cause blackouts. While blackouts are a frightening experience, treatment can allow people to lead a normal life without the fear of falling unconscious or losing their memory.

A person with bipolar disorder will experience changes in mood, energy, and activity levels that can make day-to-day living difficult.

Bipolar disorder can cause severe disruption to a person’s life, but the impact varies between individuals. With appropriate treatment and support, many people with this condition live a full and productive life.

According to the National Alliance on Mental Illness (NAMI), bipolar disorder affects over 10 million people in the United States or around 2.8% of the population.

On average, a person will receive a diagnosis around the age of 25 years, but symptoms can appear during the teenage years or later in life. It affects males and females equally.

What is bipolar disorder?

The National Institute of Mental Health describe the main symptoms of bipolar disorder as alternating episodes of high and low mood. Changes in energy levels, sleep patterns, ability to focus, and other features can dramatically impact a person’s behavior, work, relationships, and other aspects of life.

Most people experience mood changes at some time, but those related to bipolar disorder are more intense than regular mood changes, and other symptoms can occur. Some people experience psychosis, which can include delusions, hallucinations, and paranoia.

Between episodes, the person’s mood may be stable for months or years, especially if they are following a treatment plan.

Treatment enables many people with bipolar disorder to work, study, and live a full and productive life. However, when treatment helps a person feel better, they may stop taking their medication. Then, the symptoms can return.

Some aspects of bipolar disorder can make a person feel good. During an elevated mood, they may find they are more sociable, talkative, and creative.

However, an elevated mood is unlikely to persist. Even if it does, it may be hard to sustain attention or follow through with plans. This can make it difficult to follow a project through to the end.

Symptoms

According to the International Bipolar Association, symptoms vary between individuals. For some people, an episode can last for several months or years. Others may experience “highs” and “lows” at the same time or in quick succession.

In “rapid cycling” bipolar disorder, the person will have four or more episodes within a year.

Mania or hypomania

Hypomania and mania are elevated moods. Mania is more intense than hypomania.

Symptoms can include:

• impaired judgment
• feeing wired
• sleeping little but not feeling tired
• a sense of distraction or boredom
• missing work or school
• underperforming at work or school
• feeling able to do anything
• being sociable and forthcoming, sometimes aggressively so
• engaging in risky behavior
• increased libido
• feeling exhilarated or euphoric
• having high levels of self-confidence, self-esteem, and self-importance
• talking a lot and rapidly
• jumping from one topic to another in conversation
• having “racing” thoughts that come and go quickly, and bizarre ideas that the person may act upon
• denying or not realizing that anything is wrong

Some people with bipolar disorder may spend a lot of money, use recreational drugs, consume alcohol, and participate in dangerous and inappropriate activities.

Depressive symptoms

During an episode of bipolar depression, a person may experience:

• a feeling of gloom, despair, and hopelessness
• extreme sadness
• insomnia and sleeping problems
• anxiety about minor issues
• pain or physical problems that do not respond to treatment
• a sense of guilt, which may be misplaced
• eating more or eating less
• weight loss or weight gain
• extreme tiredness, fatigue, and listlessness
• an inability to enjoy activities or interests that usually give pleasure
• difficulty focusing and remembering
• irritability
• sensitivity to noises, smells, and other things that others may not notice
• an inability to face going to work or school, possibly leading to underperformance

In severe cases, the individual may think about ending their life, and they may act on those thoughts.

Psychosis

If a “high” or “low” episode is very intense, the person may experience psychosis. They may have trouble differentiating between fantasy and reality.

According to the International Bipolar Foundation, psychosis symptoms during a high include hallucinations, which involve hearing or seeing things that are not there and delusions, which are false but strongly felt beliefs. A person who experiences delusions may believe they are famous, have high-ranking social connections, or have special powers.

During a depressive or “low” episode, they may believe they have committed a crime or are ruined and penniless.

It is possible to manage all these symptoms with appropriate treatment.

Types of bipolar disorder

A person may receive a diagnosis of one of three broad types of bipolar disorder. According to NAMI, symptoms occur on a spectrum, and the distinction between the types is not always clear-cut.

Bipolar I disorder

For a diagnosis of bipolar I disorder:

• The individual must have experienced at least one manic episode.
• The person may have had a previous major depressive episode.
• The doctor must rule out other disorders, such as schizophrenia and delusional disorder.

Bipolar II disorder

Bipolar II disorder involves periods of hypomania, but depression is often the dominant state.

For a diagnosis of bipolar II disorder, a person must have had:

• one or more episodes of depression
• at least one hypomanic episode
• no other diagnosis to explain the mood shifts

A person with hypomania may feel good and function well, but their mood will not be stable, and there is a risk that depression will follow.

People sometimes think of bipolar II disorder as a milder version. For many, however, it is simply different. As NAMI indicate, people with bipolar II disorder may experience more frequent episodes of depression than people with bipolar I disorder.

Cyclothymia

The National Health Service (NHS) in the United Kingdom note that cyclothymia has similar features to bipolar disorder, but the Diagnostic and Statistical Manual of Mental Disorders, 5th Edition (DSM-5) classifies it separately. It involves hypomania and depression, but the changes are less intense.

Nevertheless, cyclothymia can impact a person’s daily life, and a doctor can provide treatment.

Diagnosis

A medical professional will diagnose bipolar disorder using criteria set out in the DSM-5.

The National Institue of Mental Health (NIMH) explain that in order to receive a diagnosis of bipolar I disorder, a person must have had symptoms for at least 7 days, or less if symptoms were severe enough to need hospitalization. They may also have had a depressive episode lasting at least 2 weeks.

To receive a diagnosis of bipolar II, a person will have experienced at least one cycle of hypomania and depression.

A doctor may carry out a physical examination and some diagnostic tests, including blood and urine tests, to help rule out other causes.

It can be challenging for a doctor to diagnose bipolar disorder, as people are more likely to seek help with a low mood than a high mood. As a result, it can be hard for them to distinguish it from depression.

If the person has psychosis, a doctor may misdiagnose their condition as schizophrenia.

Other complications that may occur with bipolar disorder are:

• use of drugs or alcohol to cope with symptoms
• post-traumatic stress disorder (PTSD)
• anxiety disorder
• attention-deficit hyperactivity disorder (ADHD)

NIMH urge healthcare providers to look for signs of mania in the person’s history, to prevent misdiagnosis. Some antidepressants can trigger mania in susceptible people.

A person who receives a diagnosis of bipolar disorder has a lifelong diagnosis. They may enjoy long periods of stability, but they will always live with the condition.

Shingles is a viral infection that results from the varicella-zoster virus (VZV), the same virus that causes chickenpox. It typically affects a single sensory nerve ganglion and the skin surface that the nerve supplies.

Anyone who has had chickenpox can later develop shingles.

In fact, according to the Centers for Disease Control and Prevention (CDC), an estimated 1 in 3 people in the United States develop shingles during their lifetime.

However, a person can only develop shingles if they have had chickenpox or exposure to the virus that causes it. This virus can lie dormant for years.

Most adults with the dormant virus never develop shingles, but for some, the virus reactivates several times.

Shingles is most common after the age of 50 years, but it can appear at any age if a person has previously had chickenpox.

In this article, learn more about shingles, including symptoms, complications, and treatments.

Symptoms

Shingles usually affects one side of the body. This is most often the waist, chest, abdomen, or back. Symptoms can also appear on the face and in the eyes, mouth, ears. The virus can also affect some internal organs.

Shingles typically affects a single sensory nerve ganglion near the spinal cord, called a dorsal root ganglion. This is why the symptoms occur in specific areas of the body, rather than all over it. The pain results from nerve involvement, rather than the rash itself.

In fact, some people have pain but no rash. Others, meanwhile, may have a rash with pain that is accompanied by other symptoms, such as fever, chills, or headache.

Symptoms can vary in nature, depending on where on the body they appear.

Common symptoms

Some of the most common symptoms of shingles include:

• a constant dull, burning, or gnawing pain, or a sharp, stabbing pain that comes and goes
• a skin rash that resembles a chickenpox rash but only affects certain areas
• fluid-filled blisters that develop as part of the rash

Symptoms on the body

A blistering skin rash may appear in one or more distinct bands with sensory nerves of the skin, called dermatomes.

Common locations for this include:

• the chest
• the abdomen
• the back
• around the waist

It usually occurs only on one side of the body.

The location of the symptoms will depend on which dermatome distribution the virus affects.

Facial symptoms

If the rash affects the face, symptoms usually appear on one side only — usually around one eye and the forehead.

They can include:

• pain over the affected dermatome
• a rash
• muscle weakness
• headache

Eye symptoms

If the virus affects an ophthalmic nerve, it means that a person has herpes zoster ophthalmicus.

This can cause pain, redness, and swelling in and around the eye, as well as temporary or permanent loss of vision.

Ear symptoms

Shingles can also occur in or around the ear, leading to problems with balance and hearing, as well as muscle weakness on the affected side of the face.

These changes can be long term or even permanent. A person who develops symptoms in or around the ears and eyes should seek immediate medical attention to reduce the risk of complications.

Mouth symptoms

If shingles affects the mouth, a person may experience:

• facial tenderness
• pain in the mouth
• toothache
• lesions in hard and soft palate tissues

The pain and discomfort of these symptoms can make it difficult to eat or drink.

Internal shingles

Shingles can also affect the internal organs. There will not be a rash, but other problems can arise.

For example, researchers have found evidence of shingles in the digestive system, which can lead to gastrointestinal dysfunction, and in the arteries in the brain, which may increase the risk of stroke and dementia.

Other symptoms

There may also be other symptoms, including:

• fever
• fatigue
• chills
• headache
• upset stomach

Symptom progression

Symptoms typically progress as follows:

• Pain, tingling, numbness, and itching start to affect a specific part of the skin.
• After up to 2 weeks, a rash appears.
• Red blotches and itchy, fluid-filled blisters develop and continue to do so for 3-5 days.
• The blisters may merge, forming a solid red band that looks similar to a severe burn. The gentlest touch may be painful.
• Inflammation may affect the soft tissue under and around the rash.
• After 7–10 days, the blisters gradually dry up and form scabs or crusts. As the blisters disappear, they may leave minor scarring.

Shingles usually lasts around 2–4 weeks. It is contagious until the blisters dry up and crust over.

Most people will only have an episode of shingles once, but it can recur in some people.

Complications

Rarely, complications can arise — especially in people with an impaired immune system.

Possible complications of shingles include:

• postherpetic neuralgia (PHN)
• inflammation of the brain or spinal cord, increasing the risk of stroke, encephalitis, and meningitis
• eye and vision problems
• weakness
• problems with balance and hearing
• damage to blood vessels, which could lead to stroke
• pneumonia

According to the CDC, around 10–18% of people who have shingles will develop PHN, a long term complication wherein the pain of a shingles rash lasts long beyond the rash itself.

It is more likely to occur if a person develops shingles after the age of 40 years, and the risk continues to increase with age.

In people with weak immune systems

People with a weakened immune system will have a higher risk of developing shingles and of experiencing severe symptoms and complications.

This include people who:

• have cancer, especially leukemia or lymphoma
• have HIV
• have undergone an organ transplant
• are taking medications to suppress the immune system, including chemotherapy drugs

These people should seek medical attention as soon as possible if they have concerns about shingles-related symptoms.

Is shingles contagious?

It is not possible to directly transmit shingles to another person. However, a person who has never had chickenpox can contract VZV by coming into direct contact with the fluid in the blisters of a person who currently has shingles.

If this happens and the person has not received vaccination against chickenpox, they would develop chickenpox first, not shingles.

Shingles does not spread through coughing or sneezing. Only direct contact with fluid from the blisters can spread the virus. Therefore, covering the blisters reduces the risk of contagion.

It is important to note that the virus is only active from when the blisters first appear to when they dry up and crust over. Transmission is not possible before the blisters develop and after the crusts form. If a person does not develop blisters, the virus cannot spread in the traditional sense.

Taking the following precautions can help prevent the transmission of the virus:

• Cover the rash.
• Wash the hands often.
• Avoid touching or scratching the rash.

It is also important to avoid contact with:

• infants who are preterm or have a low birth weight
• pregnant women who have never had chickenpox or the vaccine for it
• those with a weakened immune system

Treatment

A doctor may prescribe antiviral drugs to stop the virus from multiplying.

Antiviral treatment

Antiviral treatment can help:

• reduce the severity and duration of symptoms
• prevent complications from developing
• lower the risk of the rash coming back

Managing symptoms

Tips for managing symptoms include:

• using pain relief medication
• reducing stress as much as possible
• eating regular, nutritious meals
• getting some gentle exercise
• wearing loose fitting clothes, for comfort

To relieve itching, the CDC recommend:

• applying calamine lotion
• taking a lukewarm, oatmeal bath
• placing a cool, damp washcloth on the blisters

Most people will recover with home treatment, but a person should seek medical help if other symptoms appear, such as a fever. Around 1–4% of people will need to spend time in the hospital due to complications.