Vegan diet has become a popular diet choice for people around the world, in recent times, due to concerns such as health issues, animal rights and welfare, and sustainability of the environment. Over the years, research has explored the nutritional benefits of a vegan diet and its potential effects on health and well-being. A well-planned vegan diet contains only plant-derived foods, such as fruits, vegetables, legumes, grains, seeds, and nuts. While these natural sources offer a myriad of essential nutrients, special attention must be paid to certain key components that may be more difficult to obtain solely from plant-based sources. To prevent deficiencies and ensure overall health and well-being, particular attention must be paid to nutrients such as protein, iron, calcium, vitamin B12, vitamin D, and omega-3 fatty acids with a very long chain in a vegan diet. As adults cultivate a vegan lifestyle, their dietary choices can substantially affect their health. Many studies have identified that a well-planned vegan diet can provide numerous health benefits. Evidence supports that a vegan diet may reduce the risk of chronic diseases, such as type 2 diabetes, hypertension, and certain types of cancer. Research conducted in Adventists has presented convincing evidence that adequately balanced vegan diets are nutritionally sufficient. On the contrary, inadequate intake of critical nutrients, such as vitamin B12 and iron, can lead to anemia and other health complications if not addressed or attended appropriately. The plant-based diet index has been developed to assess intakes of both plant and animal foods, considering the quality of plant foods: overall plant-based diet index (PDI), healthful plant-based diet index (hPDI), and unhealthful plant-based diet index (uPDI). All indices negatively weigh animal foods, but differently weigh plant foods depending on their nutritional quality. Previous studies have reported that hPDI was associated with a lower risk of cardiovascular disease or type 2 diabetes.

Central to the interest in the vegan diet lies its foundation in plant-based foods, which are abundant in a diverse array of bioactive components. These constituents contribute to the potential influence of the diet on health, especially in adults . Bioactive components are inherent compounds within plant foods, which extend their impact beyond basic nutrition. Functioning as key regulators, these bioactive components modulate physiological processes and are associated with a spectrum of positive health advantages, such as antioxidant, anti-inflammatory, and anticarcinogenic properties. Flavonoids have positive effects on cardiovascular health and anti-cancer properties. Carotenoids exert protective effects against several types of cancers, in addition to their benefits for vision and skin. Glucosinolates have protective roles against cancer and dementia.

Research has indicated that a well-planned vegan diet can confer improved health benefits while aligning with principles that favor ethical and environmental concerns. However, certain knowledge gaps must be explored. By extensively exploring the nutritional components of a vegan diet and their implications for well-being, individuals, especially adults, can make informed choices about adhering to a vegan lifestyle.

Vegetarians miss out on lots of foods. No grilled burgers or franks at picnics. No holiday turkey or fries cooked in animal fat. Strict vegetarians may even forego honey made by bees. But vegetarians also tend to miss out on major health problems that plague many Americans. They generally live longer than the rest of us, and they’re more likely to bypass heart-related and other ailments.

The fact is, eating a more plant-based diet can boost your health, whether you’re a vegetarian or not.

What is it about the vegetarian lifestyle that can protect your health? And are there risks to being vegetarian? NIH-funded researchers are looking for answers. They’re exploring the many ways that diet and other factors affect our health.

Vegetarian meals focus on fruits and vegetables, dried beans, whole grains, seeds and nuts. By some estimates, about 2% of the U.S. adult population follows this type of diet.

People have many reasons for becoming vegetarians. Some want to eat more healthy foods. Others have religious or economic reasons or are concerned about animal welfare. “Vegetarian diets are also more sustainable and environmentally sound than diets that rely heavily on meat, poultry and fish,” says NIH nutritionist Dr. Susan Krebs-Smith, who monitors trends in cancer risk factors.

Most people think of vegetarian diets as simply eating plant foods and not eating meat, poultry and fish. “But in fact, there are many different types of vegetarian diets,” Krebs-Smith explains. “Some are more restrictive than others.”

Strict vegetarians, or vegans, eat plant foods and reject all animal products—meat, poultry, fish, eggs, dairy and sometimes honey. Those who also eat dairy products are called lacto vegetarians. Vegetarians who eat both dairy and eggs are called lacto-ovo vegetarians.

Some vegetarians eat fish but not meat or poultry. They’re called pescatarians (pesce is Italian for fish).

“Then there are the so-called flexitarians, or semi-vegetarians. These are people who eat a mostly vegetarian diet, but they occasionally eat meat,” says Jody Engel, a nutritionist and registered dietitian at NIH. “They might say ‘I’m a vegetarian, but I need to eat my burgers every Sunday.’ People tend to follow their own rules, which is one reason why it’s hard for researchers to study vegetarians. There’s so much variance.”

Despite the different definitions, “there’s tremendous agreement among nutrition experts and health organizations that a more plant-based diet is beneficial, whether you’re a true vegetarian or not,” says Krebs-Smith. “Most Americans don’t eat enough fruit, vegetables, legumes or whole grains. There’s a huge consensus that eating more of these foods would be a good idea for everyone.”

Vegetarian diets tend to have fewer calories, lower levels of saturated fat and cholesterol, and more fiber, potassium and vitamin C than other eating patterns. Vegetarians tend to weigh less than meat-eaters, and to have lower cancer rates. “Evidence also suggests that a vegetarian diet is associated with a lower risk of death from certain heart diseases, and that those who follow a vegetarian diet tend to have lower LDL [“bad”] cholesterol levels,” says Engel.

In some cases, though, it’s unclear if certain health benefits come from plant-based eating or from the healthy lifestyle of most vegetarians. “Vegetarians are generally more physically active and have healthier habits than non-vegetarians. They also typically have a higher socioeconomic status, at least in the United States,” says Krebs-Smith.

To tease out the effects of diet, scientists have to conduct large, carefully controlled studies that account for other factors. One of the world’s largest studies of plant-based diets is now underway at Loma Linda University in California. Cardiologist Dr. Gary Fraser is leading an NIH-funded team of scientists to analyze data on 96,000 Seventh-day Adventists in all 50 states and in Canada. Members of this religious group have unique dietary habits and a generally healthy lifestyle.

Adventists are encouraged to follow a vegetarian diet, but about half the population sometimes eats meat. These variable eating patterns allow scientists to compare a wide range of dietary habits and look for links between diet and disease.

To date, the researchers have found that the closer people are to being vegetarian, the lower their risk of diabetes, high blood pressure and metabolic syndrome (a condition that raises your risk for heart disease and stroke). “The trend is almost like a stepladder, with the lowest risks for the strict vegetarians, then moving up for the lacto vegetarians and then the pescatarians and then the non-vegetarians,” Fraser explains. Earlier studies found that vegetarian Adventists also tend to live longer than both meat-eating Adventists and non-Adventists. The vegetarians also have less coronary heart disease and lower rates of some cancers.

Because vegetarians by definition don’t eat meat, some people jump to the conclusion that simply cutting meat from your diet will lead to health benefits. “But it’s actually more complicated than that,” says Fraser. “Differences in life expectancy and other health matters might be related to the extra fruits, vegetables, nuts and legumes—including soy—that vegetarians tend to eat. You can’t necessarily conclude it’s based on the absence of meat,” he says.

Experts generally agree that vegetarians who eat a wide variety of foods can readily meet all their body’s needs for nutrients. “At any stage of life, you should be able to eat a healthy diet by consuming vegetarian foods. But it does take a little planning,” says Rachel Fisher, a registered dietitian involved in nutrition research at NIH.

Vegetarians need to be sure they take in enough iron, calcium, zinc and vitamin B12. Studies show that most vegetarians do get enough, in part because so many cereals, breads and other foods are fortified with these nutrients. “Vegans in particular need to be certain to get enough vitamin B12 and omega-3 fatty acids,” says Fisher. Omega-3—found in fish, flax seed, walnuts and canola oil—is important for heart health and vision.

Some vegetarians take dietary supplements to make sure they’re getting everything they need. It’s a good idea to talk to a registered dietitian or other health professional if you’re a vegetarian or thinking of becoming one.

Whether you’re a vegetarian or not, Fisher says, you can benefit from the high fiber, low fat and rich nutrients of a vegetarian diet. “Vegetarian foods can be so delicious, and they’re so good for you,” she says.

Try using a variety of spices and herbs to make things interesting. And make sure not to overcook your vegetables, or they might lose some of their valuable nutrients.

Tips for a Vegetarian Diet

• Meet protein needs by eating a variety of plant foods, nuts, eggs or dairy foods.
• Snack on unsalted nuts and use them in salads or main dishes.
• Vitamin B12 is naturally found only in animal products. Choose fortified foods such as cereals or soy products, or take a vitamin B12 supplement if you don’t eat animal products.
• Get calcium from dairy products and calcium-fortified soy milk, breakfast cereals or orange juice.
• Beans and peas have many nutrients and are recommended for everyone, vegetarians and non-vegetarians alike.

Numerous studies have shown how vegan diets affect body composition, particularly when it comes to losing weight. Vegan diets likely lead to weight loss because they are associated with a reduced calorie intake due to a lower fat content and a higher dietary fiber content. Calorie density is very important for reducing body weight. Consuming foods with lower calories is more advantageous for weight loss than reducing portion sizes. Foods of plant origin have a lower calorie density than foods of animal origin. Data from the Adventist Health Study (AHS) have shown that the body mass index (BMI) increases as the amount of animal foods in the diet increases. Furthermore, results from the European Prospective Investigation into Cancer and Nutrition – Oxford (EPIC-Oxford) study have shown that vegans gain significantly less weight as they age compared to omnivores. The European Prospective Investigation into Cancer and Nutrition-Physical Activity, Nutrition, Alcohol, Cessation of Smoking, Eating Out of Home and Obesity (EPIC-PANACEA) study, found a positive association between total meat consumption and weight gain, even after adjusting for energy intake: an increase in 250 g/day of meat led to a weight gain of 2 kg after 5 years (95% CI, 1.5–2.7 kg). In a study that examined a cohort of 49,098 Taiwanese adults, the percentage of participants with a BMI ≥ 27 kg/m2 was significantly lower among those following a vegetarian diet (10.9%) as compared to those following a non-vegetarian diet (15.4%). Furthermore, this study also found that for each year on a vegan diet, the risk of obesity decreased by 7%.

Vegan diets have been shown to have the lowest calorie density and the least amount of cholesterol among various plant-based diets. According to a study conducted by Kahleova et al. overweight participants with a body mass index between 28 and 40 kg/m2 were randomly assigned to follow a low-fat vegan diet in a randomized clinical trial. According to the study findings, the overweight group assigned to a vegan diet experienced a considerable decrease in fat mass and visceral fat compared to the control group. Research has shown that a vegan diet can help adults lose weight by replacing high-calorie items with low-calorie alternatives and maintaining a balance between energy intake and energy expenditure. Based on available evidence, the vegan diet should be considered a viable option for patients who are interested in preventing overweight and obesity or losing weight. Researchers report that a vegan diet is generally associated with a healthy lifestyle that excludes smoking and includes regular physical activity. It is very likely that the health benefits from such nutritional behavior are the result of the combination of these factors, and not only the diet alone. Such a lifestyle provides many benefits and can prevent some chronic lifestyle-associated diseases, including obesity and cardiovascular diseases (CVD).

Cardiovascular disease is a major cause of mortality and is currently responsible for a third of all deaths worldwide. CVD is a collection of different conditions that are directly related to the health of the heart. These include arteriosclerosis, arterial stenosis, arterial thrombosis, coronary heart disease and high blood pressure. Plant-based diets reduce CVD risk factors, as confirmed by a meta-analysis and systematic review of prospective cohort studies by Quek et al. in which they show a beneficial effect of plant-based diets in terms of reducing cardiovascular mortality and CVD. However, specifically in the context of a vegan diet, the systematic review by Kaiser et al. evaluated the usefulness of vegan diets in the prevention of cardiovascular disease. The evidence among the Western populations studied weakly suggests an association between vegan diets and the risk of cardiovascular disease. The risk of total CVD, coronary heart disease, acute myocardial infarction, primary stroke, haemorrhagic stroke and ischaemic stroke was assessed. None of the trials found a significantly increased or decreased risk of any cardiovascular complication in people who followed a vegan diet. The authors noted that due to the limited number of high-quality studies, the overall evidence on the role of a vegan diet in the development or prevention of CVD is weak. In this year’s systematic review and meta-analysis of prospective cohort studies, Dybvik et al. observed an 18% reduction in the relative risk of ischaemic heart disease among vegans. No clear association was observed between vegan diets and CVD or stroke. The authors indicated that the number of studies was limited and the associations unclear and imprecise.

Benefits of vegan diets can include reduced inflammation, blood pressure, total cholesterol, serum glucose, improved endothelial function, reduced risk of blood clots, reduction in body weight, etc.. These beneficial cardiovascular health results can be attributed to a lower intake of dietary cholesterol, saturated fat, trans fatty acids, processed meat, and a higher and more regular intake of fibre, vegetable protein, beta-carotene, vitamin C, vitamin K, folic acid and magnesium and potassium. The study by Pickering et al. highlights the importance of potassium and magnesium for the health of the cardiovascular system. The main role of potassium in the prevention of cardiovascular disease is due to its influence on maintaining electrolyte balance, reducing blood pressure, and the risk of stroke through its beneficial effects on endothelial function and vascular homeostasis, while magnesium is involved in the regulation of blood pressure and metabolism. It is worth noting that the balance between potassium and sodium is of crucial importance for the health of the cardiovascular system.

In particular, the soluble fiber fraction, through its effects on lowering total cholesterol and low-density lipoprotein (LDL) levels, better glycaemic control, weight loss, and reduced inflammation, provides a number of health benefits in the context of CVD risk reduction. According to Pereira et al. an increase in soluble fiber intake of 10 g per day can reduce the risk of a coronary event by 14% and the risk of coronary death by 27%. Furthermore, the above fiber fraction may have an effect on the production of short-chain fatty acids (SCFAs) in the colon, which in turn may potentially have an effect on cholesterol synthesis. Nevertheless, it is worth noting that in the systematic review and meta-analysis by Wang et al. vegetarian diets were effective in lowering blood levels of total cholesterol, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, and non-high-density lipoprotein cholesterol to a greater extent than control diets; however, it is unclear whether vegan diets have a similar effect. A vegan diet seems to exhibit greater efficacy in reducing overall and LDL cholesterol when compared to omnivorous control diets; nevertheless, its impact on HDL cholesterol and triglyceride levels remains inconclusive.

Vegan diets are also rich in polyphenols, which is relevant in relation to cardiovascular disease. The antioxidant capacity of polyphenolic compounds is known from in vitro studies, mainly through their role in the capture and neutralization of free oxygen and nitrogen species and protection against oxidative stress. This antioxidant capacity, possibly together with their ability to modulate nitric oxide (NO) production, enables polyphenolic compounds to contribute to the maintenance of vascular homeostasis. Through their role in inhibiting platelet aggregation, reducing vascular inflammation, modulating apoptotic processes, reducing LDL oxidation, and improving the lipid profile, polyphenols can also contribute to cardiovascular health.

The gut microbiome is another emerging pathway through which a healthy plant-based diet may influence the risk of CVD. Microorganisms in the gut metabolize a variety of dietary substrates, which can have an impact on cardiovascular health. The trimethylamine N-oxide (TMAO) pathway is an example. Choline and L-carnitine, compounds derived mainly from animal-based foods such as red meat, poultry, and fish, are broken down by microbes in the gut to produce trimethylamine (TMA), which is further broken down in the liver to form TMAO. Associated with an increased risk of cardiovascular events, TMAO is believed to affect heart health through cholesterol and sterol metabolism, inflammation, thrombotic, and atherosclerotic pathways. As a recent study did not find an association between TMAO and dietary factors, it is possible that the association of animal foods with heart disease risk through the TMAO pathway is modified by eating foods rich in TMAO precursors and by gut microbial composition. Certain phytochemicals (e.g., resveratrol) have been found to potentially inhibit TMAO production in animal model studies. Plant-based diets also differ from animal-based diets in several other microbiota-dependent metabolic pathways, including increased metabolism of dietary fiber and polyphenols, and decreased metabolism of bile acids and amino acids, which may mediate links to cardiovascular disease. To elucidate the likely complex pathways by which diet interacts with the intestinal microbial environment to influence cardiovascular health, larger studies with longer follow-up and repeated assessment of diet and microbiome are needed.

There are also limitations and risks associated with following a vegan diet for cardiovascular health, especially if the diet is poorly balanced, as vegans may have lower amounts of dietary nutrients such as eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), selenium, zinc, iodine, iron, calcium and vitamin B12, vitamin D, compared to non-vegans, which can lead to adverse cardiovascular effects. Van Winckel et al. stress that it is important to understand that both an unhealthy diet and a vegan diet can induce chronic inflammation, if the vegan diet contains insufficient amounts of nutrients and omega-3 fatty acids. One of the many issues in the context of vitamin B12 deficiency in a vegan diet is the risk of leading to hyperhomocysteinemia. As a result of reduced vascular elasticity and altered homeostasis, elevated levels of homocysteine induce vascular endothelial impairment. This is an important risk factor for CVD. It is also worth mentioning the problem of consuming large amounts of processed plant products in a vegan diet, meat substitutes and dairy substitutes, which can be high in sugars, salt, and trans fatty acids.

Most short-term studies on vegan diets do not provide accurate data on long-term effects on cardiovascular health, based mainly on changes in biomarkers. Following a vegan diet also brings about a number of health benefits in terms of cardiovascular disease, but is also associated with the risk of nutrient deficiencies. It seems that a well-balanced vegan diet, rich in high-quality plant-based foods such as whole grains, fruits, vegetables and nuts, based on unprocessed products, together with supplementation (for example, an algae-based DHA supplement in addition to regular consumption of sources of ALA and vitamin B12, vitamin D) may be considered a suitable route to the prevention of cardiovascular disease, but more research on this issue is needed. Although it requires more research and a personalized diet approach, a vegan diet may not only benefit heart health, but may also have the potential to regulate blood glucose levels and manage diabetes mellitus.

A chronic metabolic disorder called diabetes mellitus is characterised by persistently high blood glucose levels, insulin resistance, and insufficient amounts of insulin compared to physiological requirements. Due to the decreased sensitivity of the body to insulin hormone, which controls blood glucose levels, and the pancreas’ insufficient ability to produce enough insulin to compensate for this resistance, this syndrome develops.

The global diabetes prevalence in 20–79 year olds in 2021 was estimated to be 10.5% (536.6 million people), rising to 12.2% (783.2 million) in 2045. Just over half a billion people are living with diabetes worldwide which means that over 10.5% of the world’s adult population now have this condition.

Because a healthful, well-planned vegan diet may be inclusive of entirely whole plant foods such as fruits, vegetables, legumes, whole grains, nuts, and seeds, which are excellent sources of dietary fiber, it naturally contains a lot of fiber. Soluble dietary fiber can improve glycaemic control by delaying the process by which food leaves the stomach, resulting in slower glucose uptake and absorption. It is well established that a vegan diet can tackle important pathophysiological processes related to beta cell dysfunction and insulin resistance. A 16-week randomized controlled experiment with 75 overweight adults, half of whom followed a vegan diet, and the other half a control diet, illustrates this. The vegan group demonstrated a notable improvement in beta cell function and fasting insulin sensitivity compared to the control group. These two elements are recognized to be the main pathophysiological mechanisms driving type 2 diabetes. Another study has shown that fiber helps delay the absorption of glucose in the gastrointestinal tract, which causes blood glucose levels to gradually rise. This result may reduce the likelihood of insulin resistance and hyperglycemia. A study by Chester et al. showed that a low-fat vegan diet resulted in improved glycaemic control and decreased medication consumption in those with type 2 diabetes over the age of 50 years. According to the study, the weight loss effect of the vegan diet may account for a sizable amount of its effects on hemoglobin A1C levels, a measure of blood glucose control over time. A low-fat vegan diet was found to significantly improve glycaemic control in a 22-week randomized clinical trial, which included people with type 2 diabetes. In particular, the study found that the A1C readings in the vegan group dropped noticeably more than those of the other diet group. In a 12-week randomized clinical trial by Lee et al., participants diagnosed with type 2 diabetes were randomly assigned to follow a vegan diet or a conventional diet. Both diets led to lower HbA1c levels, but glycaemic control was better with the vegan diet (0.3–0.6% greater reduction) than with the conventional diet.

Quercetin, which is only found in plant foods, may be responsible for the effects of a vegan diet on the reduction of anxiety and/or depressive symptoms. Quercetin can act as a natural antidepressant by inhibiting the activity of monoamine oxidase (MAO), an enzyme that breaks down mood-regulating neurotransmitters such as serotonin, dopamine, and norepinephrine, resulting in higher levels of these neurotransmitters in the brain. This impact might reduce the signs and symptoms of anxiety and despair.

Nutrition plays an increasingly important role in maintaining optimal brain function as people age. Studies have shown a protective effect of a vegan diet against Alzheimer’s. Alzheimer’s disease is a neurological disease that typically develops with increasing age and is known to be the leading cause of dementia worldwide. It is defined by a steady deterioration in cognitive abilities, including memory, reasoning, and behavior. The effects of diet and lifestyle choices, including a vegan diet, on Alzheimer’s disease have received much attention from researchers.

Part of the protective mechanisms of a vegan diet could be attributed to its beneficial effect on the reduction of inflammatory markers in dementia and Alzheimer’s disease. Meat-based dietary patterns appear to be positively correlated with biomarkers of low-grade inflammation, whereas vegetable- and fruit-based diets are inversely correlated. Studies providing data on biomarkers of inflammation in vegans, however, are few and inconsistent. Menzel et al. found no significant differences in any of the seven inflammatory biomarkers measured. Participants who followed a vegan diet for more than 4.8 years were more likely to have lower hsCRP levels compared to those who followed a vegan diet for less than 4.8 years. This may suggest that diet length may be an important factor in reducing systemic inflammation. Šebeková et al. also found that plasma CRP levels were not significantly different between vegans and omnivores. In the other hand, Franco de Moreaes et al. identified lower values of inflammatory markers, CRP and TNF-α/IL-10 ratio in strict vegetarians compared to vegetarians and omnivores. Lastly, a recent meta-analysis showed that vegans have lower CRP levels than omnivores.

With the popularity of veganism rising rapidly, there is an increased need for scientific study to determine how a vegan diet affects human health, particularly in relation to cognitive functioning. A low-risk lifestyle adjustment that can help maintain cognitive function and prevent cognitive ageing is to switch to a vegan diet. Further research is needed to prove that a vegan diet can help prevent or counteract inflammation and subsequently help reduce the risk of Alzheimer’s disease.

Numerous health problems have been associated with adulthood and ageing, and the severity of these problems depends on various circumstances. A study by Rodrigues et al. found that ageing is related to a loss of bone mass, increasing the incidence of fractures with age. Osteoporosis is a degenerative skeletal condition that can increase the susceptibility of a person to fractures, especially in the hip, spine, and wrist. Key characteristics of osteoporosis include low bone mass and decreased bone mineral density. The health of an adult is greatly influenced by its diet, which is one of the key determinants. A vegan diet has some consequences, according to several studies conducted in the context of food. Bone health is one example. Bone health problems, which often develop with age, are substantially more common in women than in men. In general, high bone mineral density is preferred since it has a negative correlation with the risk of fragility fractures, especially in female adults. In other words, the lower the risk of fractures caused by decreased bone strength, the higher the concentration of bone mineral. Adopting a vegan diet can raise concerns about inadequate nutrient intake, which can eventually lead to lower bone mineral density (BMD). Certain nutrients, such as vitamin B12, vitamin D, calcium, and omega-3 fatty acids, may be insufficient in a vegan diet. This is so because, as cited by Richter et al. and Menzel et al., these nutrients are commonly present in animal products. Vegans showed lower bone mineral density than omnivores in a variety of bone locations, including the hip, femoral neck, and lumbar spine, according to a cross-sectional study conducted by Menzel et al., which included 36 vegans and 36 omnivores, as well as adults. Furthermore, compared to omnivores, vegans exhibited lower levels of calcium, vitamin D, and vitamin K. However, the bone turnover markers of the two groups did not show appreciable variations. The study findings indicated that vegans should consume enough calcium, vitamin D, and vitamin K to maintain strong bones because they may be more susceptible to osteoporosis and bone fractures. The study also emphasized how crucial nutrient balance is for vegan diets because vegans who consume an unbalanced diet run the risk of depleting many nutrients. Vitamin D, which is often obtained by exposure to sunlight but can also be found in foods such as fatty fish, egg yolks, and the liver, is crucial for the health of bones. The relevance of nutritional practices as a modifiable factor that affects bone mineral density has been acknowledged.

Sarcopenia and frailty syndrome are debilitating conditions primarily associated with aging-related changes in body composition, characterized by low muscle mass and strength. These conditions ultimately lead to an increased risk of adverse health outcomes such as disability, hospitalization, or death. It is estimated that sarcopenia affects 30% of individuals over 60 years old and 50% of those over 80 years old. Data analysis from 62 countries worldwide indicates a prevalence of frailty syndrome ranging from 12 to 24% of the population. This, in the face of an ever-increasing number of elderly people, is becoming a serious public health problem. A well-planned diet is essential for older people. Although the evidence base for the role of dietary protein in maintaining good muscle health in older age is strong, the importance of protein sources is an ongoing subject of research. With the increasing number of people adopting flexitarian, vegetarian, and vegan diets, scientists are highlighting the need to pay attention to the dietary habits of older people to prevent sarcopenia and frailty syndrome. The results of the study conducted by Sotos-Prieto et al. indicate that a healthful plant-based diet was associated with lower risk of frailty whereas an unhealthful plant-based diet was associated with higher risk. Adequate consumption of high-quality dietary protein combined with regular physical activity is crucial to the prevention of the aforementioned conditions among older people. Furthermore, increasing portion sizes could be helpful in improving the intake of protein and essential amino acids (EAAs) to address the challenge of the lower anabolic properties of plant-based foods and proteins. Essential amino acids are essential components found in dietary protein that play a crucial role in maintaining muscle growth and strength throughout an individual’s lifetime. Attention should be paid to the intake of branched chain amino acids (BCAAs), especially leucine, isoleucine, and valine. Ingestion of dietary protein induces hyperaminoacidemia, promoting muscle protein synthesis and inhibiting muscle protein breakdown through various pathways. However, scientific opinions on the use of a vegan diet among older individuals and its impact on the development of sarcopenia are highly divided. According to studies by Hengeveld et al. and Tieland et al., the lower quality of protein present in many vegan meals can be problematic, especially considering that a significant number of adults struggle to meet the recommended increase in dietary protein intake. According to Domić et al., older Spanish adults who consumed more animal protein than vegetable protein had a lower incidence of frailty. Additionally, researchers point out that several observational studies have shown a favorable correlation between animal-based protein and muscle mass and strength, indicating that a vegan diet might have negative effects on muscle mass and strength. The study conducted by Maroto-Rodriguez et al. provides intriguing results and a fresh perspective on the dietary habits of seniors. According to the researchers, diets with a high consumption of plant-derived foods and a lower consumption of animal-derived foods could potentially reduce the risk of frailty in elderly individuals. The study attributes positive health outcomes to the adoption of a plant-based diet, characterized by a significant intake of plant products and a lower intake of animal products. Unlike other vegetarian diets, a plant-based diet places emphasis on the quality of plant-based items. It associates the favorable impact of healthy plant-derived foods such as vegetables, fruits, whole grains, and nuts with improved health among individuals over 65, in contrast to unhealthy plant-derived products like refined grains, sugary beverages, and animal-based foods. The authors of the study suggest that the protective effect of a plant-based diet against frailty could be linked to the provision of essential nutrients. They highlight the antioxidant effects of vitamins C and E, carotenoids, and selenium derived from fruits and vegetables. These elements may protect against sarcopenia by reducing the exposure of muscle fibers to oxidative stress. However, biomarkers of selenium and zinc were lower in vegans, confirming that a sufficient supply of these trace elements is more difficult to achieve when following a plant-based diet. Additionally, the inclusion of legume and nuts protein might help prevent sarcopenia. The authors also point out the potential anti-inflammatory effects of fruits, olive oil, unsaturated fatty acids, nuts, or coffee, which may help mitigate the low-grade chronic inflammation associated with frailty. Similar results are presented by a Chinese study conducted among nearly 4,000 participants.

Researchers have shown that a vegan diet is linked to a reduced risk of frailty in men and older adults who lead a healthy lifestyle. More research is required to establish a vegan diet as a recommended dietary approach to prevent and minimize frailty among older adults. Furthermore, it should be considered to incorporate dietary interventions along with lifestyle changes to promote successful ageing, a factor that could also be significant for women.

Considering the substantial increase in the elderly population worldwide and the significance of the issue, future studies are needed to develop an optimal approach to nutrition and/or supplementation with isolated protein preparations for individuals who, for various reasons, choose to adhere to a vegan diet.

If you follow a vegan diet or one that does not include any forms of animal protein, you or your baby might not get enough vitamin B₁₂.

In a baby, B₁₂ deficiency can cause symptoms such as:

• Loss of appetite
• Slow motor development
• Being very tired
• Weak muscles
• Vomiting
• Blood problems

You can protect your and your baby's health by taking vitamin B₁₂ supplements while breastfeeding. Talk to your doctor about your vitamin B₁₂ needs.

When you reach for that bottle of vitamin C or fish oil pills, you might wonder how well they’ll work and if they’re safe. The first thing to ask yourself is whether you need them in the first place.

More than half of all Americans take one or more dietary supplements daily or on occasion. Supplements are available without a prescription and usually come in pill, powder or liquid form. Common supplements include vitamins, minerals and herbal products, also known as botanicals.

People take these supplements to make sure they get enough essential nutrients and to maintain or improve their health. But not everyone needs to take supplements.

“It’s possible to get all of the nutrients you need by eating a variety of healthy foods, so you don’t have to take one,” says Carol Haggans, a registered dietitian and consultant to NIH. “But supplements can be useful for filling in gaps in your diet.”

Some supplements may have side effects, especially if taken before surgery or with other medicines. Supplements can also cause problems if you have certain health conditions. And the effects of many supplements haven’t been tested in children, pregnant women and other groups. So talk with your health care provider if you’re thinking about taking dietary supplements.

“You should discuss with your doctor what supplements you’re taking so your care can be integrated and managed,” advises Dr. Craig Hopp, an expert in botanicals research at NIH.

Dietary supplements are regulated by the U.S. Food and Drug Administration (FDA) as foods, not as drugs. The label may claim certain health benefits. But unlike medicines, supplements can’t claim to cure, treat or prevent a disease.

“There’s little evidence that any supplement can reverse the course of any chronic disease,” says Hopp. “Don’t take supplements with that expectation.”

Evidence does suggest that some supplements can enhance health in different ways. The most popular nutrient supplements are multivitamins, calcium and vitamins B, C and D. Calcium supports bone health, and vitamin D helps the body absorb calcium. Vitamins C and E are antioxidants—molecules that prevent cell damage and help to maintain health.

Women need iron during pregnancy, and breastfed infants need vitamin D. Folic acid—400 micrograms daily, whether from supplements or fortified food—is important for all women of childbearing age.

Vitamin B12 keeps nerve and blood cells healthy. “Vitamin B12 mostly comes from meat, fish and dairy foods, so vegans may consider taking a supplement to be sure to get enough of it,” Haggans says.

Research suggests that fish oil can promote heart health. Of the supplements not derived from vitamins and minerals, Hopp says, “fish oil probably has the most scientific evidence to support its use.”

The health effects of some other common supplements need more study. These include glucosamine (for joint pain) and herbal supplements such as echinacea (immune health) and flaxseed oil (digestion).

Many supplements have mild effects with few risks. But use caution. Vitamin K, for example, will reduce the ability of blood thinners to work. Ginkgo can increase blood thinning. The herb St. John’s wort is sometimes used to ease depression, anxiety or nerve pain, but it can also speed the breakdown of many drugs—such as antidepressants and birth control pills—and make them less effective.

Just because a supplement is promoted as “natural” doesn’t necessarily mean it’s safe. The herbs comfrey and kava, for example, can seriously damage the liver.

“It’s important to know the chemical makeup, how it’s prepared, and how it works in the body—especially for herbs, but also for nutrients,” says Haggans. “Talk to a health care provider for advice on whether you need a supplement in the first place, the dose and possible interactions with medicine you’re already taking.”

For vitamins and minerals, check the % Daily Value (DV) for each nutrient to make sure you’re not getting too much. “It’s important to consider the DV and upper limit,” says Haggans. Too much of certain supplements can be harmful.

Scientists still have much to learn even about common vitamins. One recent study found unexpected evidence about vitamin E. Earlier research suggested that men who took vitamin E supplements might have a lower risk of developing prostate cancer. “But much to our surprise, a large NIH-funded clinical trial of more than 29,000 men found that taking supplements of vitamin E actually raised—not reduced—their risk of this disease,” says Dr. Paul M. Coates, director of NIH’s Office of Dietary Supplements. That’s why it’s important to conduct clinical studies of supplements to confirm their effects.

Because supplements are regulated as foods, not as drugs, the FDA doesn’t evaluate the quality of supplements or assess their effects on the body. If a product is found to be unsafe after it reaches the market, the FDA can restrict or ban its use.

Manufacturers are also responsible for the product’s purity, and they must accurately list ingredients and their amounts. But there’s no regulatory agency that makes sure that labels match what’s in the bottles. You risk getting less, or sometimes more, of the listed ingredients. All of the ingredients may not even be listed.

A few independent organizations conduct quality tests of supplements and offer seals of approval. This doesn’t guarantee the product works or is safe; it just assures the product was properly made and contains the listed ingredients.

“Products sold nationally in the stores and online where you usually shop should be fine,” Coates says. “According to the FDA, supplement products most likely to be contaminated with pharmaceutical ingredients are herbal remedies promoted for weight loss and for sexual or athletic performance enhancement.”

To make it easy to find reliable information, NIH has fact sheets on dietary supplements at ods.od.nih.gov/factsheets/list-all/. NIH also recently launched an online Dietary Supplement Label Database at www.dsld.nlm.nih.gov. This free database lets you look up the ingredients of thousands of dietary supplements. It includes information from the label on dosage, health claims and cautions.

For more personalized, on-the-go information about dietary supplements, check out NIH’s free updated app for your smart phone or tablet: My Dietary Supplements (MyDS).

The MyDS app provides the latest supplement information and lets you keep track of the vitamins, minerals, herbs and other products you take. You can even keep track of supplements taken by your parents, spouse or children.

“Deciding whether to take dietary supplements and which ones to take is a serious matter,” says Coates. “Learn about their potential benefits and any risks they may pose first. Speak to your health care providers about products of interest and decide together what might be best for you to take, if anything, for your overall health.”

Safe Use of Supplements

• Tell all of your health care providers about any dietary supplements you use. Some supplements can interact with medications or affect medical conditions.
• Read the label instructions for use.
• “Natural” doesn’t always mean safe. For up-to-date news about the safety of particular supplements, check nccam.nih.gov/news/alerts.
• Too much might be harmful. Don’t take more than the recommended dose.

Healthy eating is important at every age. Eat a variety of fruits, vegetables, grains, protein foods, and dairy or fortified soy alternatives. When deciding what to eat or drink, choose options that are full of nutrients and limited in added sugars, saturated fat, and sodium. Start with these tips:

Make simple changes

Create main dishes such as pasta primavera with vegetables and chickpeas, pizza topped with vegetables, veggie lasagna, tofu-vegetable stir-fry, and spicy bean burritos.

Think about plant-based protein

Eat a variety of plant protein foods such as black or kidney beans, cooked split peas, and yellow or green lentils. Nuts and seeds are also great options to help you meet protein needs.

Build strong bones with calcium

If you skip dairy, get calcium from fortified products like soy beverages, tofu, and some breakfast cereals and orange juices. Dark-green leafy vegetables like collard greens, spinach, and kale are sources of calcium, too.

Add nuts to your day

Choose unsalted nuts as a snack, or use them in salads or main dishes to bump up your protein, dietary fiber, and healthy fats. Slivered almonds or crushed walnuts are great on a green salad.

Have beans for dinner or lunch

Try a bean-based chili, three bean salad, or split pea soup. Beans, peas, and lentils, which are excellent sources of protein, fiber, folate, and several minerals, are recommended for everyone – vegetarians and nonvegetarians alike – because of their high nutrient content.

Enjoy a vegetarian snack

Snack on raw veggies and hummus – a Middle Eastern dip made from blended chickpeas (garbanzo beans). Hummus is rich in protein, dietary fiber, and several important minerals.

The benefits of healthy eating add up over time, bite by bite.