Are there any health risks associated with a vegan lifestyle?
Animal products are important sources of protein, non-saturated fats, iron, vitamins, and minerals in standard Western diets. Vegans are required to find alternative sources of these nutrients, and poorly planned vegan diets may provide insufficient amounts of the following nutrients:
- Beneficial (Omega 3) fats
Diets that do not include fish, eggs, or sea vegetables (seaweeds) generally lack the beneficial Omega 3 fats EPA and DHA, which are important for optimal nervous system, cardiovascular, eye and joint health. Omega 3s also keep inflammation levels in the body low. Humans are able to convert the plant-based Omega 3 fat α-linolenic acid, found in nuts and seeds into EPA and DHA, albeit with a fairly low efficiency and not in the amounts required to achieve the aforementioned benefits.
Compared with non-vegetarians, vegetarians, and especially vegans, tend to have lower blood concentrations of EPA and DHA. Vegans can obtain DHA and EPA from micro-algae oil supplements, as well as from foods fortified with DHA and EPA.
- Vitamin B-12
This nutrient is needed to protect nerves and produce healthy red blood cells. Vegans typically have a higher prevalence of vitamin B-12 deficiency. Vitamin B-12 deficiency can result in anaemia, fatigue, mood disturbance, memory and concentration difficulty, and abnormal neurological symptoms such as paresthesia (pins and needles). B-12-fortified plant foods, such as fortified soy, seaweed, cereals, and nutritional yeast can replace lost intake. Vitamin B-12 intake can also be augmented through vitamin supplements.
This is an important nutrient for absorbing oxygen into the blood and transporting it to the cells in the body. There is no greater risk of iron deficiency if you’re a vegan or vegetarian; in fact, most people on plant-based diets actually get more dietary iron. However, most people on plant-based diets usually have lower ferritin levels, which is a marker of how much iron is stored in the body.
This is because heme-iron (found in meat and animal sources of protein), is absorbed in substantially higher quantities by the body than non-heme iron found in plant foods. This means that vegans have to eat substantially more non-heme iron to get the equivalent amount of iron from animal sources. Dried beans and dark leafy greens are rich sources of iron and vitamin C, which improves the absorption of non-heme iron. Using a cast-iron skillet to prepare meals is a good way to increase the iron content of food.
This mineral is crucial for bone health and skeletal development. Vegans are at risk of falling short of the recommended daily intake for calcium. Eating more tofu, tahini, almonds and green, leafy vegetables can help to top up calcium levels.
- Vitamin D
This vitamin protects against multiple cancers and chronic diseases and helps to strengthen immunity, bones and teeth. Regularly consuming more Vitamin-D-fortified foods and spending time in the sun can help to supplement the natural production of vitamin D in the skin. In the UK, sun exposure is inadequate during the winter months to ensure sufficient production of Vitamin D in the skin.
According to guidelines issued by Public Health England, adults and children over the age of one should have 10 micrograms (mcg) of vitamin D every day during the winter months. This means that some people may need to consider taking a supplement or ensure a sufficient intake of foods fortified with vitamin D.
Deficiency of this mineral can lead to hair loss, poor healing of wounds, immunological problems, skin problems and reproductive hormone imbalance. Vegans are often considered to be at risk for zinc deficiency due to the high phytate content of a typical vegan diet. Phytates – a common component of grains, seeds, and legumes, bind zinc and decreases its availability for absorption by the body. Nuts and seeds are excellent sources of zinc, some of the best being pumpkin seeds, sunflower seeds, walnuts, cashews, almonds, pecans, chia seeds, and hemp seeds.
Most people know that the maintenance of healthy muscles requires a sufficient intake of protein. However, all of our body’s tissues and organs require protein for general maintenance, and for making new cells. Our bodies require different types of protein in different tissues and for different functions. Proteins are made up of building blocks called amino acids. When we eat proteins, they are broken down by our digestive tract into individual amino acids, which are then absorbed into the bloodstream.
Amino acids are transported to our organs and tissues where they are rebuilt to form the exact protein we need, in the right place. Our bodies are also capable of converting one type of amino acid to another. There are certain amino acids which are cannot be produced by the body, a.k.a. essential amino acids (EAAs), and which can only be found from dietary sources.
All animal-based proteins are complete sources of protein as they contain all of the EAAs required by the body. EAAs are not all present in any single plant-based food.
Therefore, replacing meat in the diet should be done by introducing (or increasing) intake of a range of vegan foods to make sure all EAAs are covered. Knowledge of which foods to mix together is therefore crucial for maintaining optimal health and functioning.
It is also important to stay away from nutrient-poor, fast-food vegan options. Instead, base your diet around nutrient-rich whole plants and fortified foods.