Summary
By eliminating all products coming from animals, people following a vegan diet are exposed to some deficiencies. In fact, they provide nutrients that are essential to the body to function and which are less present in a plant-based diet. Here are the 5 nutrients and food supplements that can be used to replace the foods not consumed in a vegan diet and avoid deficiencies.
Vitamin B12, an essential food supplement for vegan
Vitamin B12 or cobalamin, participates in many biochemical reactions including the formation of red blood cells (in synergy with vitamin B6, vitamin B9 and iron), cell renewal and the formation of DNA. Vitamin B12 is one of the few vitamins that can be stored in the body (glycogen reserves), allowing the body to have some reserves for several years. The needs recommended by the ANSES (National Agency for Food, Environmental and Work Safety) in the update of its guidelines is 4µg per day for adults. Vitamin B12 has the particularity of being contained only in products of animal origin, but not in any product from plants. That’s why, vegans are strongly exposed to a vitamin B12 deficiency. In the 2017 update of its nutritional guidelines, ANSES recommends that anyone following a vegan diet should increase their B12 intake by consuming vegan food supplements or products with similar characteristics.
Vitamin D when you are vegan
Vitamin D is involved in many physiological processes. It helps the intestinal absorption of calcium, participates in the regulation of the immune system and in muscle contraction. Vitamin D is taking a special place among vitamins because its intake is provided both by food and by synthesis of the body after exposure to ultraviolet rays (UV). The daily needs estimated by the ANSES are 15µg per day for adults. The main sources of vitamin D are animals, like cod liver oil, fish with high fat, eggs and cheese. Vitamin D for vegans would then be necessary, especially when exposure to sunlight during the year does not cover all the needs.
Iodine in case of a vegan or vegetarian diet
Iodine is a trace element that is involved in the functioning of the thyroid gland, especially in the synthesis of thyroid hormones such as triiodothyronine (T3) and tetra-iodothyronine (T4), which has an important role in the processes of growth and cell maturation as well as in thermogenesis (regulation of body temperature). If the body doesn't have enough Iodine, the metabolism can go wrong and have serious consequences for your balance and well-being. The foods that contain Iodine the most are fish, shellfish and milk. Iodized salt and seaweed are also good sources of iodine and are available to buy in shops. Plants do not contain an interesting quantity of iodine to cover the needs estimated at 150µg per day according to the ANSES. Moreover, sea salts and salty seasonings such as soy sauce are generally not filled in iodine. The same is true for salt used for industrial food (ready meals, canned food...). Therefore, vegans who do not consume iodized salts or seaweed salts may be at risk of iodine deficiency.
Selenium, an important trace element
Selenium is also a trace element present in the body, in a really low quantity but it's quite important. Its antioxidant action role is well known, which helps fight free radicals. It has an impact on the protection of the skin, as well as on the quality of the vision. It also participates in the good maintenance of the immune system. The main sources of selenium are: cheese, fatty fishes (salmon, herring...), liver, poultry. Vegetables are interesting sources of selenium but only when they come from regions with rich soil, which is not always the case. In fact, taking a vegan food supplement containing selenium can be useful in regions of Europe where the soils are poor in selenium like France.
Omega 3: supplementing with EPA and DHA when you are vegan?
Omega 3s are anti-inflammatory fatty acids that limit platelet aggregation and are involved in brain structure. Among the omega 3, we have : alpha-linolenic acid (ALA) with a short chain from EPA (eicosapentaenoic acid) and DHA (docosahexaenoic acid) with a long chain. The vegan diet, by not consuming seafood, is deprived of DHA. The body is able to convert ALA into DHA. However, according to some studies, the efficiency of this conversion is low and exposes vegans to omega 3 deficiencies in the form of DHA. The main source of omega 3 in the form of vegetable DHA available to date is a microalgae named: Schizochytrium, that you can get with a food supplement.
