Vegan Diets: Unhealthy And Unbalanced

Veganism is a lifestyle and diet that is growing in popularity, especially among young people. While a vegan diet has been linked to a decreased risk of cardiometabolic diseases, it has also been associated with adverse health outcomes, such as nervous, skeletal, and immune system impairments, and mental health problems.

Vegans are at risk of nutritional deficiencies, particularly in vitamin B12, which can lead to neurological and haematological problems. A lack of vitamin B12 has also been linked to an increased risk of certain cancers. Vegans may also be deficient in vitamin D, calcium, zinc, and iron, and are at a higher risk of bone fractures.

A vegan diet can be healthy, but it requires careful planning to ensure nutritional needs are met.

Lack of vitamin B12, which can cause neurological and haematological problems

Vitamin B12, also known as cobalamin, is essential for cell growth and a healthy nervous system. It is naturally found in meat, poultry, and eggs, which are all excluded from a vegan diet.

Vitamin B12 deficiency can lead to serious health issues, including neurological and haematological problems.

Neurological Problems

Neurological problems associated with vitamin B12 deficiency include elevated plasma homocysteine (Hcy) concentrations (hyperhomocysteinaemia), which is a risk factor for neurological disorders. Vitamin B12 deficiency can also cause pernicious anaemia and damage to the central nervous system (demyelination).

Haematological Problems

Haematological problems associated with vitamin B12 deficiency include megaloblastic anaemia, which can have serious clinical consequences. The symptoms of vitamin B12 deficiency appear gradually over time and can be obscured by high folate levels, which can mask some of the typical vitamin B12 haematological manifestations.

Preventing Vitamin B12 Deficiency on a Vegan Diet

It is important for vegans to regularly monitor their vitamin B12 levels and ensure they are meeting their daily requirements through supplements or fortified foods. Some common vegan-friendly foods that are fortified with vitamin B12 include cereals, bread, plant milk, and nutritional yeast.

Long-Term Health Risks

If left untreated, vitamin B12 deficiency can lead to irreversible detrimental health effects. There is also growing research suggesting that inadequate vitamin B12 intake may contribute to carcinogenesis, increasing the risk of certain types of cancer.

Special Populations at Risk

Pregnant women, breastfeeding women, and children are at a higher risk of vitamin B12 deficiency and require careful dietary planning to ensure adequate intake.

Lack of calcium and vitamin D, which can increase the risk of fractures

Calcium is needed to maintain healthy bones and teeth. Non-vegans get most of their calcium from dairy foods like milk, cheese, and yoghurt, but vegans can get it from other foods. Good sources of calcium for vegans include green, leafy vegetables like broccoli, cabbage, and okra, as well as fortified unsweetened soya, pea, and oat drinks, sesame seeds and tahini, dried fruit, and bread.

Vitamin D helps regulate the amount of calcium and phosphate in the body, keeping bones, teeth, and muscles healthy. Good sources of vitamin D for vegans include exposure to sunlight, fortified foods like fat spreads, breakfast cereals, and unsweetened soya drinks, and vitamin D supplements.

Vegans are at risk of calcium and vitamin D deficiencies, which can increase the risk of osteoporosis and bone fractures. A study reported that vegans had a greater incidence of overall fracture, leg fractures, and fractures in other major sites. The higher risk of fractures may be related to vegans' significantly lower calcium intake, reduced dietary protein intake, and lower BMI.

To avoid calcium and vitamin D deficiencies, vegans should ensure they consume enough calcium-rich foods and get adequate sun exposure. They may also consider taking supplements, especially during the autumn and winter months.

Lack of omega-3 fatty acids, which can cause cardiovascular disease and cancer

A vegan diet may be deficient in omega-3 fatty acids, which are mainly found in animal products. Omega-3 fatty acids are essential for human health, and their absence can lead to cardiovascular disease and cancer.

Omega-3 fatty acids, including eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), are crucial for maintaining good cardiovascular health. They can reduce the risk of atherosclerotic cardiovascular disease by lowering triglyceride levels, stabilising membranes, and exhibiting anti-inflammatory and anti-thrombotic properties. Studies have shown that omega-3 fatty acids can lower the risk of major coronary events, such as heart attacks and strokes. Additionally, they can help prevent unstable angina and the need for heart stenting procedures.

The human body cannot produce omega-3 fatty acids, so they must be obtained through diet. While some plant-based sources, such as chia, flax, canola, hemp, walnuts, and olive oil, contain omega-3 fatty acids, they are present in much higher quantities in animal-based foods. The exclusion of animal-sourced foods from a vegan diet can lead to a deficiency in omega-3 fatty acids, which has been linked to an increased risk of cardiovascular disease.

Furthermore, omega-3 fatty acids play a vital role in cancer prevention. Studies have shown that a diet rich in omega-3 fatty acids can reduce the risk of certain types of cancer, including colorectal, breast, cervical, and gastrointestinal cancers. This is because omega-3 fatty acids can help maintain healthy cell growth and a stable nervous system. A deficiency in omega-3 fatty acids can lead to elevated levels of plasma homocysteine, which is a risk factor for neurological disorders and cardiovascular problems.

In conclusion, a vegan diet may be deficient in omega-3 fatty acids, which are essential for maintaining cardiovascular health and preventing cancer. While plant-based sources of omega-3 fatty acids exist, they may not be sufficient to meet the body's requirements, especially when compared to animal-based sources. Therefore, vegans should be mindful of their omega-3 fatty acid intake to avoid potential health risks associated with deficiencies.

Lack of zinc, which can cause mental health problems

Zinc is an essential trace element required by all organisms for various biological processes. Its deficiency can lead to neuropsychiatric manifestations that can present as altered behaviour and cognition, reduced ability to learn, and depression. Clinical studies have shown that low levels of zinc intake contribute to the symptoms of depression and patients suffering from depression have a lower serum zinc level.

Zinc is predominantly sequestered within glutamatergic neurons, typically acting as an inhibitory modulator at the NMDA glutamate receptor. It is released into the synapse with glutamate and rapidly reaches micromolar ranges, a level at which it physiologically regulates many synaptic processes.

Zinc is an essential element obtained from dietary sources, particularly red meat, poultry, fish, and dairy. Its concentration is normally maintained by easy absorption in the digestive tract, but insufficiency can be related to dietary habits, ageing, medical comorbidities (including alcoholism and H Pylori) and numerous common medications (including antacids, diuretics, anticonvulsants, anti-retrovirals, hormones, steroids, other anti-inflammatories, and numerous cardiovascular medications).

Zinc deficiency can lead to depression, increased anxiety, irritability, emotional instability, and induced deficits in social behaviour. The hippocampus is a site of lifelong neurogenesis, with decreased BDNF expression and diminished neuro/synaptogenesis accompanying episodes of major depression. Rodents fed a diet deficient in zinc demonstrated reduced zinc levels in the hippocampal vesicles, an area of the brain that normally has higher concentrations, with accompanying decreases in progenitor cells and immature neurons. The contrary was observed with zinc-enriched diets, with an increase in progenitor cells.

Zinc interacts with BDNF levels and its deficiency thereby decreases neurogenesis and depressive symptoms ensue. An inverse correlation was observed between serum BDNF levels and depression severity in one clinical trial. The exact relationship between BDNF and zinc is being elucidated, although a possible role for zinc in synaptogenesis includes its role in transactivating TrkB, a crucial neurotrophic factor. Zinc's activation of TrkB is independent of BDNF activation and produces hippocampal mossy fibre potentiation. Further studies with mice suggest that not only zinc is required for mossy fibre potentiation, it can also inhibit it postsynaptically. This suggests that zinc may be required as a dual control to maintain homeostasis.

Zinc thus regulates synaptic plasticity, aiding in neurogenesis and preventing pathological states.

Lack of iron, which can cause fatigue and inability to concentrate

Iron is a crucial mineral for the human body, and a deficiency can lead to a range of health issues. Iron is needed to make haemoglobin, a protein in red blood cells that carries oxygen through your blood vessels. When the body doesn't get enough iron, it can't produce enough haemoglobin, leading to a condition called iron deficiency anaemia.

Iron deficiency anaemia is characterised by fatigue and an inability to concentrate due to a lack of oxygen reaching the body's tissues and muscles. This results in feelings of tiredness and exhaustion, as the heart has to work harder to pump oxygen-rich blood around the body.

Vegan diets have been associated with iron deficiencies due to the absence of animal-based foods, which are typically rich sources of iron. Plant-based sources of iron, known as non-heme iron, are less bioavailable, meaning the body finds it harder to absorb this type of iron.

To prevent iron deficiency and its associated symptoms, it is important to include iron-rich foods in the diet. For vegans, this may include dried fruit, sea vegetables, leafy green vegetables, and beans. Additionally, consuming vitamin C with plant-based iron sources can enhance iron absorption.

It is worth noting that fatigue and an inability to concentrate can have various causes and are not always related to iron deficiency. However, if these symptoms persist, it is advisable to consult a healthcare professional, who can perform the necessary tests and provide guidance on dietary changes or supplements to address any deficiencies.

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