Recently, vegan diets have experienced an increase in popularity, thanks, in part, to celebrities like Zac Effron, Benedict Cumberbatch and Beyonce, to name a few. This diet has been trending, but it’s not just a celebrity-inspired fad, it has more health benefits such as:
- higher content of fibre, folic acid, vitamins C and E, potassium, magnesium and many phytochemicals;
- many of the foods are rich in unsaturated fats;
- contain less saturated fat and cholesterol and more dietary fibre;
- vegans tend to be slimmer, have lower serum cholesterol and lower blood pressure, reducing their risk of heart disease.
Unfortunately, veganism may pose some health threats. In this article, we’ll discuss the possible risks and how to avoid the pitfalls commonly associated with such a diet.
Specific nutrients are lacking or hard to find in an exclusively plant-based diet. As vegans, we should keep an eye on vitamins (like B12 and A), minerals (such as calcium, iron and zinc), long-chain fatty acids (omega 3), other polar lipids and a balanced amino acid spectrum.
Vitamin Deficiencies on a vegan diet
The vegan diet is usually very low in vitamin B12 and A. Because these vitamins are lacking in plant-based foods, it is hard for the body to get enough to absorb from them.
Vitamin B12 is the “Energy Vitamin” because it plays an essential role in the production of the red blood cells, and the proper functioning of your nervous system. It is also necessary for the production of DNA needed to make new cells. Without it, the instructions for building these cells are incomplete and cells are unable to divide.
Deficiency of vitamin B12 causes tiredness, lack of energy, muscle weakness, problems with the nervous system, pins and needles (paresthesia), disturbed vision, depression, confusion, problems with memory, understanding and judgement, anaemia, heart conditions, temporary infertility, pregnancy complications and congenital defects.
B12 is only found naturally in animal foods and yeast extracts, so supplementation is a must for vegans.
Vitamin A is vital to make sure the immune system works properly, to help with eye health and night vision and to maintain healthy teeth, bones and skin.
Although the vegan diet rarely lacks vitamin A, as it is present as beta-carotene, some vegans may need to supplement this vitamin, particularly those with recurrent respiratory system infections and poor sleep.
Our bodies convert beta-carotene into vitamin A. However, some people do not carry out this conversion easily. A good tip to increase absorption of beta-carotene from fruits and vegetables, is to consume it with a fat source, e.g. a study shows that eating a carrot with avocado or oil dressing will increase the conversion of vitamin A by almost 7 times as compared to eating carrots alone.
Mineral Deficiencies
Vegans should keep an eye on their intake of calcium, zinc and iron. This is because these minerals are less available from plant-based food, other compounds hinder their absorption, and they are relatively scarce in the soils they are grown in.
Calcium is a crucial mineral to keep our bones and teeth healthy, help our muscles work efficiently and support the function of our nervous system.
Achieving the recommended daily amount of calcium can be difficult, not only because the foods vary significantly in the amount of calcium they contain, but also the body absorbs the calcium in various foods differently. For example, spinach, rhubarb, beans, seeds, nuts, and grains are high in calcium, but they also contain oxalic acid and phytic acid. These two acids bind with the calcium and prevent the body from absorbing it.
Also, foods that contain high levels of sulfur amino acids or with diuretic effects (such as coffee, cereals, nuts and seeds) increase the urine excretion of calcium.
Iron is another mineral that vegans may struggle to absorb.
Heme iron contains a protective structure known as a porphyrin ring. This ring makes it easier for the body to absorb the iron due to its protecting effects from other elements or compounds in proximity and by shielding it from acids, phytates or other potentially harmful elements that interfere with the iron absorption process. Also, the presence of specific proteins in the system helps to give the body’s heme absorption rate a boost. Iron found in animal products is a heme type while non-heme iron, commonly found in plant foods, can be converted to a usable form. However, due to the low absorption rate, it may remain in the gut causing side effects.
A good meal plan, rich in the iron cofactors (like vitamin C and B12), can improve iron absorption from a plant source.
Lastly, vegans need to be especially aware of zinc, since its availability is lower in plant foods and it can vary depending on how much zinc is in the soil where they were grown.
The body requires zinc to produce over 300 enzymes used to enhance immune function, recovery, wound healing, fertility and eye health.
We can find zinc in beans, legumes, and grains. Phytic acid can hinder zinc absorption, like it does to calcium. However, by soaking or sprouting grains and beans before cooking, you can reduce the phytic acid content.
Amino Acid Imbalance
Amino Acids are the structural units of the proteins. They give our bodies structure as part of our muscles and bones, help fight infection, carry oxygen and assist growth and tissues repair.
Amino acid deficiency can cause hair, nail, and skin problems, weakness, muscle fatigue, increased hunger, slowed healing, decreased immune system response, mood changes and adrenal exhaustion.
A vegan diet may be short on some amino acids; only hemp and soy products have a complete spectrum, closely mimicking those found in human proteins. Other plant-derived proteins have a lower percentage of at least one amino acid, creating some deficiencies.
Always blend your grains and legumes to achieve a complete amino acid range.
Omega-3 Deficiency
There are three main forms of omega-3’s: eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), and alpha linolenic acid (ALA). Most of the health benefits of omega-3 are linked to EPA and DHA.
A vegan diet is rich in the ALA form. Sources are seeds, nuts and vegetable oils.
It’s commonly estimated that just 5%-10% of ALA is converted to EPA and 2%-5% makes it to DHA. Also, only 1% of the western population and 3% of the eastern population has the enzyme for the conversion. So, this means 90% of your EPA and DHA is being lost during digestion. To make things worse, a plant-based diet is very high in omega 6, which makes it harder to convert ALA to EPA and DHA, reducing the conversion rate by an additional 50%.