Vegan Diet: Healthy Or Harmful?

A vegan diet is a plant-based diet that excludes all animal products, including meat, dairy, and eggs. While some people adopt veganism for ethical or environmental reasons, others are drawn to the potential health benefits. Research suggests that a vegan diet can support weight loss, improve heart health, protect against certain cancers, and lower the risk of type 2 diabetes. However, a vegan diet may also be more demanding in terms of nutritional requirements, as it can be deficient in certain nutrients like vitamin B12, calcium, and iron. Well-planned vegan diets that include a variety of plant-based foods and supplements can help ensure adequate nutrient intake.

Nutritional deficiencies

Vitamin B12

Vitamin B12 is mainly found in animal products, and vegans may need to supplement their diet with vitamin B12 to prevent deficiency. Vitamin B12 is essential for cell growth and a healthy nervous system. Some vegan-friendly sources of vitamin B12 include fortified cereals and plant milk, nutritional yeast, and yeast spreads.

Iron

Iron is crucial for blood health, and while a vegan diet can be high in iron, the body absorbs iron from plant-based sources less efficiently than from meat. Good vegan sources of iron include wholemeal bread, iron-fortified breakfast cereals, dark leafy greens, and dried fruits like apricots, prunes, and figs.

Calcium

Calcium is essential for maintaining healthy bones and teeth. Vegans can get calcium from green leafy vegetables like broccoli and cabbage, fortified unsweetened plant-based milk, sesame seeds, tahini, and bread. However, it's important to note that spinach, while high in calcium, is not a good source as the body cannot fully digest it.

Vitamin D

Vitamin D is crucial for bone health and protecting against cancer and chronic health conditions. Sun exposure is an excellent source of vitamin D for vegans, but supplementation or consuming vitamin D-fortified foods may also be necessary during winter months or for those with limited sun exposure.

Omega-3 Fatty Acids

Omega-3 fatty acids are important for heart, eye, and brain function. Walnuts, flaxseeds, and seaweeds are good plant-based sources of omega-3. However, vegans should be mindful that plant sources of omega-3 may not have the same benefits for heart health as those found in oily fish.

Zinc

Zinc is important for the immune system and is found in beans, nutritional yeast, nuts, and oats. However, zinc absorption can be inhibited by phytates found in whole grains, so it's important to soak and sprout beans, seeds, and grains to improve zinc absorption.

Iodine

Iodine is essential for thyroid function, and a deficiency can lead to mental retardation and thyroid dysfunction. Vegans can get iodine from seaweed and fortified foods. However, it's important to monitor iodine intake as both overconsumption and underconsumption can lead to thyroid issues.

Overall, while a vegan diet can provide all the necessary nutrients, careful planning is required to avoid potential nutritional deficiencies.

Health problems

A vegan diet can be more demanding on your body if it is not well-planned. Poorly planned vegan diets may lead to nutritional deficiencies and health problems.

Nutritional Deficiencies

A vegan diet may not provide sufficient amounts of vitamin B12, niacin, riboflavin (vitamin B2), vitamin D, calcium, iodine, selenium, or zinc.

Vitamin B12 is mainly present in animal products and protects the nerves and red blood cells. Plant-based sources include fortified cereals and plant milk, nutritional yeast, and yeast spreads.

Iron is important for blood health and can be obtained from beans and dark leafy greens.

Calcium is crucial for bone health and can be obtained from tofu, tahini, and leafy greens.

Vitamin D protects against cancer and chronic health conditions and helps strengthen bones and teeth. It can be obtained from spending time in the sun and eating vitamin D-fortified foods.

Omega-3 fatty acids are important for heart, eye, and brain function, with walnuts and flaxseeds being good plant-based sources.

The potential health problems associated with a vegan diet are mainly due to nutritional deficiencies. These may include:

• Increased risk for certain types of cancer, stroke, bone fractures, preterm birth, and failure to thrive.
• Higher rates of depression and anxiety.
• Hair loss, weak bones, muscle wasting, skin rashes, hypothyroidism, and anemia.
• Gout, chronic kidney disease, and cardiovascular disease (due to high levels of uric acid).

However, it is important to note that these health problems are not inevitable and can be avoided by ensuring a well-planned and balanced vegan diet that includes a variety of plant-based foods and, if necessary, supplements or fortified foods.

Planning a Healthy Vegan Diet

To avoid potential health problems, it is important to plan a vegan diet carefully to ensure all nutritional requirements are met. This includes:

• Eating at least 5 portions of a variety of fruits and vegetables every day.
• Including fortified dairy alternatives, such as soy drinks and yogurts, and fortified foods or supplements for vitamin D, vitamin B12, iodine, selenium, calcium, and iron.
• Consuming beans, pulses, nuts, and seeds regularly.
• Choosing unsaturated oils and spreads and eating them in small amounts.
• Drinking plenty of fluids.
• Limiting the intake of high-fat, salty, and sugary foods.

Weight loss

A vegan diet can be an effective way to lose weight. Research shows that individuals consuming plant-based diets (PBDs) tend to have lower body mass indexes (BMIs) than those consuming non-PBDs. This is likely due to the fact that a vegan diet tends to be lower in calories, saturated fat, and cholesterol, and higher in fiber.

A literature review published in Frontiers in Nutrition found that a PBD is a beneficial approach to improving health, particularly in obese patients, with benefits including weight loss, improved cardiovascular health, lower blood pressure, and improved glucose metabolism.

Several studies have shown that a vegan diet can lead to significant weight loss. For example, a review of 15 clinical trials found that PBDs were associated with a mean weight loss of 3.4 kg, while another meta-analysis of clinical trials found that participants assigned to a PBD lost an average of 2.02 kg more than those assigned a non-vegetarian diet.

It is important to note that, as with any nutritional plan, weight loss on a vegan diet depends on overall calorie reduction and additional lifestyle changes. Simply eliminating animal products may not lead to weight loss if the diet is still high in calories and processed foods.

• Focus on whole, unprocessed plant-based foods such as fruits, vegetables, whole grains, legumes, nuts, and seeds. These foods are nutrient-dense and can support weight loss and overall health.
• Practice portion control and mindful eating. Even when consuming plant-based foods, overeating can hinder weight loss goals.
• Optimize protein intake by incorporating various plant-based protein sources such as legumes, tofu, tempeh, and seitan. Protein aids in satiety and supports weight loss efforts.
• Understand the role of fats and incorporate healthy fats in moderation, such as avocados, nuts, seeds, and plant-based oils. These provide satiety and contribute to overall satisfaction with meals.
• Balance macronutrients and aim for a balanced distribution of complex carbohydrates, proteins, and healthy fats. This supports sustained energy levels, promotes fullness, and aids in weight management.
• Prioritize physical activity in addition to a vegan diet for effective weight management. Engage in activities you enjoy, such as walking, cycling, dancing, or fitness classes, and include strength and resistance activities at least twice a week to maintain lean muscle mass while losing weight.

Lowered risk of chronic diseases

A vegan diet is associated with a reduced risk of chronic diseases, including cancer, heart disease, and hypertension. A study funded by the NIH/National Cancer Institute found that vegans had the lowest risk of these diseases compared to other dietary groups, including lacto-ovo-vegetarians, semi-vegetarians, pesco-vegetarians, and non-vegetarians.

The vegan diet is rich in fruits, vegetables, whole grains, and legumes, which are excellent sources of beta-carotene, fiber, and omega-3 fatty acids. This diet is also associated with lower intakes of saturated fatty acids. The vegan group in the study was the only group with a healthy weight range, while all other groups were, on average, overweight.

The health benefits of a vegan diet are further supported by a cohort study of 126,394 UK adults, which found that a healthful plant-based diet was associated with a 16% lower risk of all-cause mortality. This study also showed that an unhealthy plant-based diet, characterized by higher intakes of sugary drinks, snacks, and desserts, was associated with a 23% higher risk of all-cause mortality.

The positive impact of a vegan diet on chronic disease risk may be attributed to its ability to reduce obesity, low-grade inflammation, and impaired insulin sensitivity. Additionally, plant-based diets can beneficially affect the composition and function of the large intestinal microbiome, which has been linked to a reduced risk of cardiovascular disease and certain cancers.

Overall, a well-planned vegan diet that includes a variety of whole foods and fortified foods or supplements can effectively lower the risk of chronic diseases and promote overall health.

Ethical, environmental, and health reasons for veganism

Veganism is a diet and lifestyle that is growing in popularity. Vegans typically avoid all animal-based foods, such as meat, fish, eggs, and dairy, and often extend this to animal byproducts, like gelatin, and products produced by bees, such as honey.

There are several reasons why someone might choose to adopt veganism, including ethical, environmental, and health reasons.

Ethical Reasons

One of the main ethical reasons for veganism is the belief that it is wrong to exploit animals for human gain. This includes the belief that animals suffer or are stressed due to the conditions in which they are kept, and the ways in which they are killed for human consumption.

Environmental Reasons

Environmental vegetarianism and veganism are practised to create a sustainable diet and avoid the negative environmental impact of meat production. Livestock is estimated to be responsible for around 15% of global greenhouse gas emissions, with four-fifths of agricultural emissions arising from the livestock sector. The livestock industry is also the primary driver of biodiversity loss and deforestation, and it significantly contributes to water and land use, pollution, and unsustainability.

A shift towards plant-based diets has been advocated by several organisations, including the Intergovernmental Panel on Climate Change, the World Scientists' Warning to Humanity, and the World Wildlife Fund.

Health Reasons

Vegan diets are often promoted as being beneficial to heart health. They are also associated with weight loss, lower blood sugar levels, and improved kidney function. Vegans tend to have lower body mass indexes (BMIs) and lower blood sugar levels, and may have a lower risk of developing type 2 diabetes and certain cancers.

However, it is important to note that a poorly planned vegan diet may lead to nutritional deficiencies in vitamin B12, omega-3, calcium, zinc, iron, magnesium, and high-quality protein. These deficiencies may be associated with an increased risk of certain types of cancer, stroke, bone fractures, preterm birth, and failure to thrive.

In conclusion, veganism has several ethical, environmental, and health benefits. However, it is important to approach a vegan diet with care to ensure adequate nutrition and avoid potential health issues.

Frequently asked questions