Everything you need to know about plant based diets
A plant based diet is one that focuses on only or mostly foods from plant sources. This way of eating may have benefits for both a person’s health and the planet.
In this article, we look at what a plant based diet is, the health benefits, and what nutritional considerations a person should make before switching.
What is a plant based diet?
A plant based diet is a diet that involves consuming mostly or only on foods that come from plants. People understand and use the term plant based diet in different ways.
Some people interpret it as a vegan diet, which involves avoiding all animal products.
For others, a plant based diet means that plant foods, such as fruits, vegetables, whole grains, nuts, and legumes, are the main focus of their diet, but they may, occasionally, consume meat, fish, or dairy products.
A plant based diet also focuses on healthful whole foods, rather than processed foods.
Following a plant based diet offers many possible health benefits, including:
Better weight management
Research suggests that people who eat primarily plant based diets tend to have a lower body mass index (BMI) and lower rates of obesity, diabetes, and heart disease than those who eat meat.
Plant based diets are high in fiber, complex carbohydrates, and water content from fruit and vegetables. This may help to keep people feeling fuller for longer and increase energy use when resting.
A 2018 study found that a plant based diet was effective for treating obesity. In the study, researchers assigned 75 people who were overweight or had obesity to either a vegan diet or a continuation of their regular diet, which contained meat.
After 4 months, only the vegan group showed a significant weight loss of 6.5 kilograms (14.33 pounds). The plant based vegan group also lost more fat mass and saw improvements in insulin sensitivity, whereas those who consumed a regular diet with meat did not.
A 2009 study on more than 60,000 people also found that vegans had the lowest average BMI, followed by lacto-ovo vegetarians (those that eat dairy and eggs) and pescatarians (people who eat fish but no other meat). The group with the higher average BMI were nonvegetarians.
Lower risk of heart disease and other conditions
A 2019 study from the Journal of the American Heart Association found that middle aged adults who ate diets high in healthful plant foods and low in animal products had a lower risk of heart disease.
According to the American Heart Association, eating less meat can also reduce the risk of:
- high blood pressure
- high cholesterol
- certain cancers
- type 2 diabetes
Diabetes prevention and treatment
Plant based diets may help people prevent or manage diabetes by improving insulin sensitivity and reducing insulin resistance.
Of the 60,000 people studied in 2009, only 2.9% of people on a vegan diet had type 2 diabetes, compared to 7.6% of those eating a nonvegetarian diet.
People eating vegetarian diets that included dairy and eggs also had a lower risk of type 2 diabetes than meat eaters.
Researchers have also looked at whether following a plant based diet can help treat diabetes. The authors of a 2018 review indicate that vegetarian and vegan diets could help people with diabetes reduce their medication needs, lose weight, and improve other metabolic markers.
The authors suggested that doctors might consider recommending plant based diets to people with prediabetes or type 2 diabetes. While veganism showed the most benefits, the researchers stated that all plant based diets would lead to improvements.
People wanting to try a plant based diet should try one that they think they can follow long term.
Foods to eat
People should focus on eating the following food groups when transitioning to a plant based diet:
A plant based diet includes all fruits, such as:
- citrus fruits
A healthful plant based diet contains plenty of vegetables. Including a variety of colorful vegetables provides a wide range of vitamins and minerals.
Root vegetables are a good source of carbohydrates and vitamins. They include:
- sweet potato
- butternut squash
Legumes are an excellent source of fiber and plant based protein. People can include a wide variety in their diet, including:
- kidney beans
- black beans
Seeds are a great snack or an easy way to add extra nutrients into a salad or on top of a soup.
Sesame seeds contain calcium and sunflower seeds are a good source of vitamin E. Other seeds include:
Nuts are a good source of plant based protein and vitamins, such as selenium and vitamin E.
It is vital to consume polyunsaturated and monounsaturated fats, as well as omega-3 fatty acids. Plant based sources include:
- chia seeds
- hemp seeds
- olive oil
- canola oil
Whole grains are an excellent source of fiber and help maintain stable blood sugar. They also contain essential minerals, such as magnesium, copper, and selenium.
Examples of whole grains include:
- brown rice
- wholegrain bread
Plant based milk
If people want to reduce their dairy intake, there is a wide range of plant based milk available in grocery stores and online. These include:
Just make sure to choose unsweetened plant milk options.
Foods to avoid
Just reducing or eliminating animal products does not automatically mean a plant based diet is healthful. It is also vital to reduce or avoid unhealthful foods, such as:
- processed foods
- sugary foods, such as cakes, biscuits, and pastries
- refined white carbohydrates
- processed vegan and vegetarian alternatives that may contain a lot of salt or sugar
- excess salt
- fatty, greasy, or deep fried foods
Before starting a plant based diet, people should ensure they take steps to get enough of the following nutrients:
Vitamin B-12 is an essential nutrient for blood and cell health. B-12 deficiency can lead to anemia and nerve damage. B-12 is present in many animal products but not in many plant based foods.
People who eat a vegan or even a vegetarian diet could consider taking a B-12 supplement or consume products fortified with B-12. Foods include some cereals, plant based milk, and nutritional yeast.
People following a plant based diet may have to ensure they get enough iron in their diet, as it has lower bioavailability in plants than meat.
Plant based foods that are a good source of iron include:
- kidney beans
- black beans
- tomato juice
- dark leafy greens
Make sure to combine citrus and other vitamin C sources with plant based sources of iron to increase absorption.
Some people may have concerns about getting enough protein from a plant based diet. However, there is a wide variety of plant based sources of protein, including:
- beans, such as kidney, pinto, or black beans
Consuming proteins from a variety of food sources can help provide all the necessary amino acids for good health. For example, people could add a handful of seeds or a spoonful of hummus to tofu or beans.
Omega-3 fatty acids
Omega-3 fatty acids are essential as they help reduce inflammation, memory loss, and other chronic conditions, such as heart disease. The two primary omega-3 fatty acids are EPA and DHA.
Fish, seafood, and animal products, such as eggs are among the primary sources EPA and DHA.
While several plant based foods, such as walnuts, hempseed, and flaxseed, contain omega-3 ALA, research shows that the body is slow and inefficient at converting ALA to EPA and DHA. Some people are also genetically at risk for poor absorption of ALA.
Vegetarians exhibit lower levels of DHA and EPA in blood and tissue, which may increase inflammation, memory difficulties, brain fog, and other effects. People following a plant based diet might want to consider taking an omega-3 supplement.
Some dietitians advise vegetarians to reduce the amount of pro-inflammatory linoleic acid they consume. Soybean, corn, sunflower, and safflower oils contain linoleic acid.
Eating a diet higher in plant foods and lower in animal products can have many health benefits, including weight loss or maintenance and a lower risk of heart disease and diabetes.
If people want to make the switch to a plant based diet, they can start by gradually reducing their meat and dairy intake.
Eating an entirely plant based meal once a week, or swapping out one animal product for a plant based one, can be an excellent place to start.
People may also wish to speak to a doctor or dietitian before making significant changes in their diet.