A healthy, nutritious diet is essential for your physical and mental well-being.
Veganism is gaining in popularity worldwide due to its reported health benefits, environmental benefits, and animal welfare benefits.
A vegan diet avoids all animal-based food products (beef, fish, poultry, eggs, and dairy products) while consuming plant-based foods.
Animal products have been a major part of Western diets for decades, with meat consumption seen as a symbol of status and wealth in soceity. Although meat is a good source of protein, vitamins and minerals, it could be detrimental to our health. Studies have shown that high intakes of red meat, and processed meat products have been linked to cardiovascular disease, obesity, and cancers (Pan et al., 2012; Song et al., 2016).
Vegan diets consist of plant-based foods rich in whole grains, legumes, nuts, seeds, fruits, and vegetables, while avoiding all animal-origin food products.
In this article we explain (in plain English!) the conclusions of scientific studies that have looked at veganism.
There are several variations of a vegetarian diet:
Drawbacks of Veganism
In this section, we will discuss the drawbacks of a vegan diet.
It is important to consult with your doctor or a dietitian before choosing to follow a vegan diet.
Although veganism has numerous health benefits, it is essential to educate yourself on ways to eat a balanced, healthful vegan diet, and avoid falling into the trap of consuming more processed, plant-based foods (refined carbohydrates such as pasta, white bread, crisps, and sweets) with low nutrient densities. These foods are generally lacking in fibre and essential nutrients which ultimately leads to nutrient deficiencies which can cause harmful effects to your health.
Potential drawbacks of an unbalanced, restrictive vegan diet are nutritional deficiencies in:
(Source: Melina et al., 2016)
Let’s cover each, in turn:
Vegans following an unbalanced, restrictive diet could be at risk of a low daily protein intake. It is important to ensure you are receiving adequate amounts of daily protein to meet your needs.
Dietary protein is essential for (Caballero, 2005):
It is possible to consume adequate amounts of protein (including all essential amino acids) with a vegan diet, if consuming a variety of plant-based foods throughout the day (Mangels, 2011).
Legumes (chickpeas, black beans, lentils, and soy) and nuts (almonds, walnuts, and cashews) are all good sources of protein, and provide many other beneficial nutrients (Messina, 2014).
Consult with a dietitian if you are concerned that you are not consuming enough protein in your diet.
Vitamin B12 is found mostly in animal-based food products (fish, meat, poultry, eggs, dairy products, and fortified cereals). Vegans are particularly at risk of vitamin B12 deficiency, with plant-based products containing little to no vitamin B12 (Green et al., 2017).
Vitamin B12 is essential for the nervous system and blood.
It plays an essential role in DNA synthesis, brain and nerve cell function, and red blood cells. Deficiency may lead to neurological disorders, autoimmune gastritis, and megaloblastic anaemia (Stabler, 2013).
Vegans should monitor their vitamin B12 levels, and supplement where necessary.
Omega-3 Fatty Acids
Omega-3 fatty acids play an essential role in the development and repair of brain, retina (eyes), and cell membranes (Melina et al., 2016).
There are various types of omega-3 fatty acids: ALA (alpha-linolenic acid) is found mainly in plant sources (seeds and nuts), while EPA (eicosapentaenoic acid) and DHA (docosahexaenoic acid) are found in animal sources (fatty fish). Vegan diets are generally absent of EPA and DHA (Sanders, 2009). Fortunately, ALA is able to convert into EPA (Melina et al., 2016).
It is possible to consume adequate amounts of omega-3 fatty acids with a vegan diet “Evidence suggests that n-3 needs of healthy individuals can be met with ALA alone, and that endogenous synthesis of EPA and DHA from ALA is sufficient to keep levels stable over many years” (Melina et al., 2016).
Plant-based sources of omega-3s include seeds (flax, chia, and hemp) and walnuts.
When choosing to follow a vegan diet, it is important to consume a variety of plant-based foods to ensure that you are consuming enough energy, protein, vitamins and minerals from various sources, this will ensure that your body is receiving adequate nutrients and prevents deficiencies.
Benefits of Veganism
Despite the drawbacks of veganism covered in the previous section, numerous studies have reported the many health benefits of a veganism.
In the sections that follow we highlight studies that have linked veganism with health benefits such as:
According to the Academy of Nutrition and Dietetics “An appropriately planned vegetarian, including vegan, diets are healthful, nutritionally adequate, and may provide health benefits for the prevention and treatment of certain diseases. These diets are appropriate for all stages of the life cycle, including pregnancy, lactation, infancy, childhood, adolescence, older adulthood, and for athletes” (Melina et al., 2016).
A vegan diet could aid in weight loss and weight management.
A review published in the journal, Nutrients, investigated the effect of plant-based diets on body weight, body mass index (BMI) and waist circumference on participants with type 2 diabetes (T2D) who usually consumed a diet containing meat. They found that adherence to a plant-based diet was effective in weight loss “vegan dietary patterns are effective in reducing body weight in overweight and obese adults as well as those with T2D” (Austin et al., 2021).
Research conducted by Huang et al. (2016), evaluating the effect of a vegetarian diet on weight loss, reported that participants who adopted a vegetarian diet had greater weight loss than those who adhered to a non-vegetarian diet “Vegetarian diets appeared to have significant benefits on weight reduction compared to non-vegetarian diets” (Huang et al., 2016).
Reduced Blood Pressure
A vegan diet may reduce your risk of developing high blood pressure.
A review published in the journal, Nutrients, examined the effectiveness of a vegetarian diet on reducing blood pressure. Vegetarian, including vegan diets were successful at lowering blood pressure “vegetarian diets are associated with significant reductions in blood pressure compared with omnivorous diets; a vegan diet demonstrated a greater reduction in systolic blood pressure” (Lee et al., 2020).
Reduced Diabetes Risk
Diabetes mellitus is a health condition characterised by glucose intolerance and insulin resistance. It affects more than 400 million individuals globally, and is considered one of the leading risk factors for cardiovascular disease.
Veganism may reduce your risk of developing diabetes.
A review published in the journal, Nutrients, looked at the influence of a vegetarian and vegan diet on diabetes risk. They found that a vegetarian, especially vegan diet was associated with a reduced risk of developing diabetes “a vegetarian diet has a protective effect against diabetes risk” (Lee & Park, 2017).
A study published in the journal, Nutrition, Metabolism and Cardiovascular Diseases, investigated the association of diet and risk of diabetes. Adherence to a vegan diet was associated with lower chance of developing diabetes “Vegetarian diets (vegan, lacto ovo, semi-) were associated with a substantial and independent reduction in diabetes incidence” (Tonstad et al., 2013).
Protective Against Cardiovascular Disease
Veganism could offer protective benefits against cardiovascular disease.
A study published in the journal, Nutrients, investigated the cardio-metabolic benefits of a plant-based diet. They found that a well-planned, healthful plant-based diet was able to control weight and blood-sugar levels, while providing protection against cardiovascular disease “plant-based diets may reduce the risk of coronary heart disease events by an estimated 40% and the risk of cerebral vascular disease events by 29%” (Kahleova et al., 2017).
Scientists from the University of Oxford examined the relationship between a vegetarian diet and the risk of developing ischemic heart disease (also known as coronary heart disease). They found that vegetarians had a 32% lower risk of IHD than non-vegetarians “Consuming a vegetarian diet was associated with lower ischemic heart disease risk” (Crowe et al., 2013).
According to Le & Sabate (2014), “Compared to lacto-ovo-vegetarian diets, vegan diets seem to offer additional protection for obesity, hypertension, type-2 diabetes, and cardiovascular mortality”.
Veganism may reduce the risk of developing metabolic syndrome.
Metabolic syndrome is a group of conditions such as obesity, diabetes, and high blood pressure which are risk factors for cardiovascular disease.
A study published in the journal, Nutrients, evaluated the effectiveness of a vegan diet in prevention and treatment of metabolic syndrome (MetS). A vegan diet was effective in prevention and management of MetS “this dietary pattern seems to be useful in the prevention and treatment of MetS and CVDs if well-planned by a nutritionist” (Marrone et al., 2021).
Veganism may offer protective benefits against cancer.
Scientists from The Department of Experimental and Clinical Medicine at the University of Florence, evaluated the link between vegetarian and vegan diets and risk of total cancer and specific cancer (colorectal, breast, prostate and lung). A vegan diet was linked to a lower chance of developing cancer, “Vegan diet conferred a significant reduced risk (−15%) of incidence from total cancer” (Dinu et al., 2017).
A study published in The American Journal of Clinical Nutrition, investigated the relationship between dietary habits and rate of prostate cancer. Adherence to a vegan diet resulted in a significantly reduced risk of developing prostate cancer “Vegan diets may confer a lower risk of prostate cancer” (Tantamango-Bartley et al., 2015).
Improved Gut Health
Veganism may lead to improved gut health.
A study published in Frontiers in Nutrition, investigated the differences in microbiomes of vegan and omnivorous individuals. They found that those adhering to a vegan diet had more health promoting compounds in their gut “Vegans had significantly lower abundances of potentially harmful (such as p-cresol, lithocholic acid, BCAAs, aromatic compounds etc.) and higher occurrence of potentially beneficial metabolites (SCFAs)” (Prochazkova et al., 2022).
A study published in the journal, Nutrients, examined the effects of a low-fat vegan diet on gut microbiota in overweight participants. The low-fat vegan diet beneficially influenced the composition of gut microbiota and lead to weight reduction and improved insulin sensitivity “A low-fat vegan diet induced significant changes in gut microbiota, which were related to changes in weight, body composition, and insulin sensitivity in overweight adults” (Kahleova et al., 2020).
A review published in Frontiers in Nutrition, analysed at the influence of a vegan diet on human gut microbiota. They found that a vegan diet produced a beneficial impact on gut microbiota and health “A vegetarian/vegan diet is effective in promoting a diverse ecosystem of beneficial bacteria to support both human gut microbiome and overall health” (Tomova et al., 2019).
Veganism could support the needs of athletes and may even improve performance.
Scientists from the University of Quebec, investigated the differences in endurance and muscle strength of vegans and omnivores. All participants adhered to either a vegan or omnivore diet for at least 2 years. Vegans had greater estimated VO2 max and submaximal endurance time to exhaustion “a vegan diet does not seem to be detrimental to endurance and muscle strength in healthy young lean women. In fact, our study showed that submaximal endurance might be better in vegans compared with omnivores” (Boutros et al., 2020).
A study conducted by scientists from Innsbruck, Austria examined the health status (body weight, mental health, chronic diseases, hypersensitivity reactions and medication intake) of vegan endurance runners compared to omnivores. They reported that a vegan diet provided optimal health conditions for endurance runners “a vegan diet, is associated with a good health status and, thus, at least an equal alternative to an omnivorous diet for endurance runners” (Wirnitzer et al., 2019).
Reduced Fibromyalgia Symptoms
Fibromyalgia is a medical condition which is characterised by pain affecting the whole body, leading to sleep problems, and emotional and mental distress.
Veganism may be an effective diet aiding in reduction of fibromyalgia symptoms and improving quality of life.
A review published in the International Journal of Environmental Research and Public Health, examined the effect of vegan and vegetarian diets on individuals with fibromyalgia. Vegan diets were effective at alleviating the negative symptoms of fibromyalgia “Mainly plant-based diets such as vegetarian or vegan diets seem to reduce fibromyalgia symptoms and improve the quality of life of these patients. Body composition, sleep quality, depression and body inflammation have improved following these dietary patterns” (Nadal-Nicolas et al., 2021).
Scientists from the University of Kuopio, in Finland investigated the effectiveness of a vegan diet in reducing fibromyalgia symptoms. Adherence to a vegan diet for 3 months resulted in reduced pain, joint-stiffness, and improved quality of sleep “vegan diet had beneficial effects on fibromyalgia symptoms” (Kaartinen et al., 2000).
Reduced Rheumatoid Arthritis Symptoms
Rheumatoid arthritis is an autoimmune disease, where the body’s immune system attacks healthy cells and leads to painful swelling and inflammation in affected joints.
Veganism could be effective at reducing symptoms of rheumatoid arthritis.
A study published in The Journal of Alternative and Complementary Medicine, evaluated the effect of a 4-week low-fat vegan diet on individuals suffering from rheumatoid arthritis. A significant reduction in all rheumatoid arthritis symptoms were observed. C-reactive protein (a marker for inflammation in the body) decreased by 16 %, and rheumatoid arthritis factor decreased by 10 % “patients with moderate-to-severe rheumatoid arthritis, who switch to a very low-fat, vegan diet can experience significant reductions in rheumatoid arthritis symptoms” (McDougall et al., 2002).
Scientists from the Department of Physiology at the University of Kuopio, Finland evaluated the effectiveness of a vegan diet rich in antioxidants on patients with rheumatoid arthritis. They reported that adherence to a vegan diet rich in vitamin C, carotenoids and vitamin E lead to a reduction in rheumatoid symptoms “rheumatoid patients subjectively benefited from the vegan diet rich in antioxidants, lactobacilli and fibre” (Hanninen et al., 2000).
Improved Psoriasis Symptoms
Psoriasis is a skin condition characterised by dry, red, itchy skin.
A vegan diet may assist in alleviating symptoms and improve skin condition.
A study published in the journal, Dermatology and Therapy, evaluated the effectiveness of dietary habits on psoriasis outcomes. Seventy percent of patients following a vegan diet reported an improvement in skin conditions “Specific diets with the most patients reporting a favourable skin response were Pagano (72.2%), vegan (70%), and Paleolithic (68.9%)” (Afifi et al., 2017).
Veganism offers environmental benefits such as reduced greenhouse gas emissions, reduced land use, and fertiliser use.
A study published in the journal, Sustainability, evaluated which diet has the lowest environmental impact on our planet. They found that a vegan diet had the least detrimental impact on our environment “the vegan diet is the optimal diet for the environment because, out of all the compared diets, its production results in the lowest level of GHG emissions” (Chai et al., 2019).
According to Springmann et al. (2018), “Dietary changes towards healthy, low-meat diets can be effective in reducing greenhouse gas emissions, moderately effective in reducing cropland use and fertiliser application in high-income and middle-income countries”.
In conclusion, scientific evidence supports the fact that a vegan diet provides numerous benefits to your health, including:
A well-planned, balanced vegan diet rich in healthful plant-based foods such as wholegrains, legumes, fruits, vegetables, nuts and seeds can provide you with the nutrition your body need to grow and stay healthy.
It is important to consult with your primary physician to monitor for deficiencies and supplement where necessary.