Vegan Diet: Unhealthy And Unbalanced?

Veganism has been associated with adverse health outcomes, including nervous, skeletal, and immune system impairments, hematological disorders, and mental health problems. This is due to the potential for micro and macronutrient deficits, such as vitamin B12, omega-3, calcium, zinc, iron, and magnesium. Vegans are also at risk of consuming fewer essential amino acids and high-quality protein. However, some studies indicate a reduction in mortality associated with veganism and improvements in cardiovascular health, blood glucose control, and blood pressure.

Risk of vitamin B12 deficiency

Vitamin B12 is an essential micronutrient that plays a vital role in supporting red blood cell production, energy, metabolism, and nerve function. It is not found in plants, so vegans are at a much higher risk of vitamin B12 deficiency than vegetarians. This is especially true for pregnant women, with deficiency rates as high as 62%. In vegetarians, B12 deficiency is as high as 40%.

Vitamin B12 deficiency can cause a wide range of symptoms, including extreme tiredness, lack of energy, tinnitus, breathlessness, feeling faint, headaches, pale skin, noticeable heartbeats, loss of appetite, and weight loss. If left untreated, it can lead to nerve damage, which can affect balance and coordination. It can also cause a type of anaemia called ‘megaloblastic anaemia’, where the red blood cells are large and fragile and break down, causing an excess of bilirubin, which gives the skin and whites of the eyes a yellow tinge.

To prevent vitamin B12 deficiency, vegans should either eat fortified foods two to three times a day to get at least three micrograms of B12 or take a daily supplement of at least 10 micrograms. They can also take a weekly B12 supplement of at least 2000 micrograms. It is important to note that the less frequently you obtain B12, the more B12 you need to take, as it is best absorbed in small amounts.

The following foods are fortified with B12 and suitable for vegans:

• Some plant milks
• Some soy products
• Some breakfast cereals
• Yeast extract, such as Marmite or yeast flakes
• Some plant milk alternatives
• Soya yoghurts

Risk of iron deficiency

Vegans need up to 1.8 times more iron than people who eat meat. This is because non-heme iron from plant-based foods is less bioavailable, with absorption hindered by whole grains, legumes, and nuts due to their phytic acid content.

Iron is a mineral essential for proper growth and development. The body uses it to make hemoglobin and certain hormones. Hemoglobin is a protein in red blood cells that carries oxygen from your lungs to all parts of the body. Myoglobin, another protein made by iron, brings oxygen to your muscles.

Low levels of iron can lead to an iron deficiency called anemia. The symptoms of anemia include pale or yellowish skin, dizziness or lightheadedness, fatigue, low body temperature, and headaches, among others.

There is a misconception that a vegan diet is missing iron, however, vegans are no more likely to develop iron deficiency anemia than the general population. This is because their diet is typically high in vitamin C, which improves the absorption of non-heme iron.

• Blackstrap molasses
• Lentils
• Tofu and tempeh
• Spinach
• Beans, such as kidney beans, soybeans, and lima beans
• Swiss chard

Risk of calcium deficiency

Calcium is a crucial component of a healthy body. It is well known for its role in building and maintaining bones, but it is also important for muscle contraction, blood pressure regulation, nerve transmission, and blood clotting.

The human body does not produce calcium, so it is essential to consume enough through food sources. While dairy products are often considered the main source of calcium, there are also many plant-based sources, including:

• Chinese cabbage
• Kale
• Broccoli
• Collards
• Mustard greens
• Calcium-set tofu
• Navy beans
• White beans
• Almonds
• Tahini
• Dried figs
• Fortified products such as plant-based milk

However, it is not just the amount of calcium consumed that matters, but also its bioavailability – or how easily the body can absorb it. The bioavailability of calcium from plant sources depends on the extent to which oxalates or phytates are present, as these inhibit absorption. Blanching, soaking, and sprouting are effective ways to reduce the number of oxalates and phytates in vegetables without negatively affecting their nutritional composition.

The recommended daily calcium intake varies depending on age and other factors, but generally ranges from 350 mg for young children to 1,000 mg for adolescent boys. For adults, the U.S. Recommended Dietary Allowance is 1,000 to 1,200 mg per day.

A lack of calcium in the diet can lead to osteoporosis, or weakness of the bones, which increases the risk of fracture. This is because, when the body does not get enough calcium from food, it reabsorbs it from the bones, which act as a reservoir.

While low calcium intake can lead to osteoporosis, excessive intake (hypercalcaemia) can also cause health problems, including poor kidney function, tissue calcification, and constipation. However, developing hypercalcaemia is rare unless one consumes high amounts of dairy products, calcium supplements, or excessive amounts of calcium-enriched food. The maximum recommended intake for adults between 19 and 50 years old is 2,500 mg of calcium per day.

Research has shown that vegans tend to have lower calcium intakes than vegetarians and meat-eaters, and they should strive to meet calcium recommendations. While it is possible to meet these recommendations by eating greens alone, the average vegan probably won't without drinking a glass of a calcium-fortified beverage each day, eating calcium-set tofu, or taking a supplement.

Risk of zinc deficiency

Zinc is a mineral that is crucial for vital reactions in the body. It helps with cell growth and reproduction, processing nutrients, wound healing, a healthy immune system, healthy vision, and more. The recommended daily intakes for zinc are 7-8 mg for women and 9.5-11 mg for men.

Vegan diets have been associated with zinc deficiency. Meat, dairy, and eggs contain zinc, but some zinc-rich plant foods (e.g., nuts, seeds, and whole grains) have poor bioavailability due to the presence of phytate, which inhibits absorption in the gut. However, it is not difficult to prevent zinc deficiency by getting your daily dose from plant foods. The best plant sources of zinc include beans, lentils, tofu, tempeh, oats, wholemeal bread, whole wheat pasta, quinoa, brown rice, pumpkin seeds, hemp seeds, other nuts and seeds, and tahini.

At the other end of the spectrum, too little zinc over long periods can cause various skin problems, hair thinning, weak immune system, slow wound healing, tiredness, diarrhea, loss of appetite, mental slowness, and impaired vision.

Zinc deficiency can be prevented by including multiple sources of zinc in the diet and reducing phytate content through various methods such as soaking and sprouting beans, grains, and seeds, as well as cooking, fermenting, and leavening.

Some studies have shown that vegetarians have similar serum zinc concentrations to, and no greater risk of zinc deficiency than, non-vegetarians, despite differences in zinc intake. However, other studies have found that vegetarians may have a lower zinc intake than non-vegetarians, and their zinc status may be protected after an initial adjustment period.

Risk of higher rates of depression and anxiety

There is a relationship between veganism and depression, with studies showing higher rates of depression among vegans compared to the general population. However, the evidence is mixed, with some studies showing a positive effect of a vegan diet on mental health.

Nutritional Deficiencies

Nutrient deficiencies resulting from a vegan diet can negatively impact mental health and cause or worsen depression and anxiety. A vegan diet may be deficient in certain key nutrients such as vitamin B12, folate, omega-3 fatty acids, and amino acids, which are essential for brain function and mood regulation. Vitamin B12, for example, is important in regulating serotonin and other mood-controlling chemicals, and its deficiency can lead to a type of anemia that causes fatigue, forgetfulness, and lethargy. Omega-3 fatty acids play a crucial role in brain function, especially memory and mood. A well-planned vegan diet can help manage the risk of these deficiencies.

Individual Factors

The impact of a vegan diet on mood is highly dependent on the individual. Some people report improved mood and reduced anxiety when following a vegan diet, while others experience the opposite effect. For some, the stress of constantly defending their dietary choices to non-vegans or striving for perfectionism with veganism can contribute to anxiety. Additionally, it is suggested that people with pre-existing mental health issues may be more likely to adopt a vegan diet as a way to reduce their symptoms.

Diet Quality

The quality of the vegan diet also plays a role. A high-quality vegan diet, rich in whole foods, fruits, vegetables, nuts, seeds, legumes, and whole grains, is associated with reduced depressive symptoms. In contrast, a low-quality vegan diet, characterised by ultra-processed and refined foods, may be linked to an increased risk of depression.

Other Factors

Other factors that may contribute to the relationship between veganism and depression include biological, social, and cultural factors. For example, higher inflammation markers are present in individuals with depression, and a low-quality diet high in ultra-processed foods can contribute to inflammation. Additionally, food restriction and the exclusion of entire food groups in a vegan diet may also impact mental health.

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