Vegan Diet: Healthy Or Hazardous?

The vegan diet has gained popularity in recent years, with people choosing to adopt it for ethical, environmental, or health reasons. While a vegan diet has been linked to several health benefits, such as lower rates of heart disease, type 2 diabetes, and certain cancers, there are also potential health risks associated with this dietary pattern. One of the main concerns is nutritional deficiencies, especially in vitamin B12, omega-3, calcium, zinc, iron, magnesium, and high-quality protein. These deficiencies can lead to an increased risk of certain cancers, stroke, bone fractures, preterm birth, and mental health issues such as depression and anxiety. Additionally, vegans may experience hair loss, weak bones, muscle wasting, skin rashes, hypothyroidism, and anemia. However, it is important to note that these risks can be mitigated by choosing the right vegan foods and supplements. The impact of a vegan diet on health is a complex topic that requires further research, and it is always advisable to consult a healthcare professional before making significant dietary changes.

Risk of anaemia due to a lack of heme iron

A vegan diet can increase the risk of anaemia due to a lack of heme iron, which is more readily absorbed by the body than non-heme iron. Heme iron is found in animal products, while non-heme iron is found in vegan foods. As a result, vegans may need to be more vigilant about ensuring they consume enough iron.

Iron is essential for producing healthy red blood cells, which carry oxygen throughout the body. When iron levels drop too low, it can lead to iron deficiency anaemia, causing symptoms such as fatigue, dizziness, pale skin, low body temperature, and headaches.

While it is possible to get enough iron from plant-based sources, it is important to be aware of the factors that can hinder iron absorption. For example, certain foods like coffee, tea, dairy products, and dietary fibre can interfere with iron absorption. On the other hand, pairing iron-rich foods with vitamin C can enhance absorption.

To prevent iron deficiency anaemia, vegans should include plenty of iron-rich plant-based foods in their diet, such as whole grains, leafy greens, beans, legumes, and dried fruit. They may also consider taking iron supplements, especially if they have a history of anaemia or are at a higher risk for iron deficiency.

It is worth noting that meat-eaters are also at risk of iron deficiency anaemia, and that a well-planned vegan diet can provide adequate iron intake. However, the risk of anaemia due to inadequate iron absorption is a valid concern for those following a vegan diet.

Increased risk of depression with low omega-3 fatty acid intake

A vegan diet may lead to nutritional deficiencies and health problems. One of the most common deficiencies in a vegan diet is omega-3 fatty acids. Omega-3 fatty acids are primarily found in fish oil and certain marine algae. They are known to be important for normal metabolism and can easily travel through the brain cell membrane, interacting with mood-related molecules inside the brain. They also have anti-inflammatory actions that may help relieve depression.

Depression is a complex, polygenic, heterogeneous, multifactorial brain disorder that affects an individual's mood, energy, and enjoyment in life. It is considered the most widespread disease globally, with hundreds of millions of people suffering from major depressive disorder.

Research has shown that omega-3 fatty acids are effective in treating depression. Omega-3 fatty acids have been found to reduce the synthesis of eicosanoids, which are involved in inflammation and proinflammation. They also compete with arachidonic acid for amalgamation into membrane-based phospholipids, reducing cellular and plasma concentrations of arachidonic acid. Additionally, omega-3 fatty acids hamper the release of pro-inflammatory cytokines, which are linked to depression and bipolar disorder.

However, the data regarding the efficacy of omega-3 fatty acids in depression treatment are conflicted. Some studies have shown that omega-3 fatty acids are effective in treating depression, while others have found no significant benefit. The conflicting results may be due to various factors such as experimental design, sample size, biological and genetic differences among patients, and environmental variability.

Overall, omega-3 fatty acid deficiencies due to a vegan diet may increase the risk of depression. While some studies suggest that omega-3 fatty acids are effective in treating depression, more high-quality clinical trials are needed to confirm their efficacy and determine their long-term safety.

Risk of vitamin B12 deficiency

Vitamin B12 is an essential nutrient that is not made by plants, and therefore unfortified plant-based foods are not a reliable source. As a result, vegans are at a high risk of vitamin B12 deficiency. This is because B12 is only found in substantial quantities in animal products, which are passed through the food chain from the bacteria that make it.

Vitamin B12 is integral to two vital cellular metabolic reactions and is essential for the synthesis of blood cells and brain nerve tissue. Low vitamin B12 status and deficiency are more common in vegans, largely due to low dietary exposure.

The symptoms of vitamin B12 deficiency may be subtle and are often ascribed to stress or other lifestyle events. Even as more symptoms manifest, they may be misinterpreted, because vitamin B12 deficiency can occur without serum levels being below the usual diagnostic cut-off. Signs and symptoms include cognitive changes (such as depression, memory impairment, confusion, psychosis, and tiredness), dyspnoea, loss of sensation, postural hypotension, muscle weakness, or loss of mental and physical drive.

The British Dietetic Association advises that those following a vegan diet should use certified vitamin B12 supplements and consume B12-fortified foods.

Preventing B12 Deficiency

To get the full benefit of a vegan diet, vegans should do one of the following:

• Eat fortified foods two or three times a day to get at least three micrograms (mcg or µg) of B12 a day
• Take one B12 supplement daily providing at least 10 micrograms
• Take a weekly B12 supplement providing at least 2000 micrograms

Inhibition of zinc absorption

Zinc is a vital mineral that supports several bodily functions, including DNA and protein synthesis, growth and development, immune and metabolic functions, and wound healing. While zinc can be sourced from meat, liver, and red meat, it can also be obtained by eating a well-balanced plant-based vegan diet. The recommended daily allowance of zinc is 9.5mg for adult men and 7mg for adult women.

Plant-based sources of zinc include tofu, cashews, sunflower seeds, garbanzo beans, lentils, peanuts, almonds, pecans, tempeh, kidney beans, peas, chia seeds, walnuts, peanut butter, corn, pinto beans, pistachios, miso, and broccoli.

However, zinc absorption may be inhibited by the presence of phytates, commonly found in whole grains and legumes. This can be mitigated by food processing techniques such as fermentation, soaking, and sprouting. Additionally, taking iron supplements close to meals may inhibit zinc absorption as the two nutrients compete for uptake. To enhance zinc absorption, it is recommended to consume protein-rich foods along with zinc supplements and include legumes and nuts, which are high in both zinc and protein.

Zinc deficiency can lead to impaired wound healing, poor growth and development, delayed sexual maturity, behavioural issues, hair loss, dry skin, acne, diarrhoea, and loss of appetite.

Low intake of iodine

Iodine is a mineral that the body uses to make certain hormones, such as those produced by the thyroid gland. A low-iodine diet is usually recommended for those undergoing radioactive iodine therapy for thyroid cancer.

A vegan diet may be low in iodine if it does not include iodized salt or sea vegetables. Iodine deficiency can lead to an enlarged thyroid gland, hypothyroidism, and impaired mental and physical development in infants and children. Vegans are advised to have regular and reliable sources of iodine, such as iodized salt, iodine supplements, or certain sea vegetables like kombu or hiziki.

However, it is easy to get too much iodine from sea vegetables, which can also cause health problems. High-iodine sea vegetables should be limited, and it is recommended to consult a doctor before taking iodine supplements.

Low Iodine Intake and Vegan Diets

Vegan diets that do not include iodized salt or sea vegetables may be low in iodine. Iodine is necessary for the proper functioning of the thyroid gland, and a deficiency can lead to health problems.

Health Risks of Low Iodine Intake

Iodine deficiency can cause an enlarged thyroid gland, known as goiter. It can also lead to hypothyroidism, a condition where the thyroid gland does not produce enough hormones. Additionally, iodine deficiency can impair mental and physical development in infants and children.

Recommended Sources of Iodine for Vegans

To ensure adequate iodine intake, vegans are advised to include regular and reliable sources of iodine in their diets. Iodized salt is one simple way to meet iodine needs, as it is commonly available and can be used in cooking and at the table.

For those who prefer to avoid salt, iodine supplements can be an alternative source. However, it is recommended to consult a doctor before taking any supplements, as too much iodine can also cause health problems.

Certain sea vegetables, such as kombu or hiziki, can also serve as sources of iodine. However, it is important to limit the consumption of high-iodine sea vegetables, as it is easy to get too much iodine from these sources.

Overall, while a vegan diet may be low in iodine, there are simple ways to ensure adequate intake, such as including iodized salt or taking iodine supplements. However, it is important to be cautious and not exceed the recommended daily intake of iodine, as excessive iodine can also have negative health effects.

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