Updated: Jun 22, 2022
More and more people are switching to a plant-based diet which can be either flexitarian, vegetarian or vegan. The last is based on a strict plant-based diet. It excludes meat, dairy products, fish and also products derived from insects such as bee products. Some people adopt this diet for their health, the rights and respect of animals, the environment and much more. By eliminating many foods from your diet, you may be missing out on certain micronutrients and macronutrients. In order not to suffer from any nutrient deficiency, it is necessary to be well guided on this subject. Contact me for specific advice. This text explains the 7 nutrients that can be the most problematic, either rarer or more difficult to absorb when following a vegan diet. Divided into two parts, this article first reveals the roles and sources of micronutrients and then the macronutrients that you need to be aware of when being vegan.
Iron, Folic Acid et vitamin B12
Iron helps in the production of red blood cells and in the transport of oxygen in the blood. Anemia can be caused by iron deficiency, vitamin B12 (cobalamin) deficiency, vitamin B9 (folate) or the 3 together and other medical conditions. On the one hand, non-heme iron (plant origin) is more difficult for our body to absorb than heme iron (animal origin). It is therefore essential to include foods containing iron in our diet such as tofu, lentils, quinoa, white beans, fortified cereals, certain dark green leafy vegetables, dried apricots, etc. (Health Canada, 2018). On the other hand, vitamin C (ascorbic acid) helps in the absorption of iron. It is found in many fruits and vegetables such as oranges, peppers, strawberries, tomatoes, etc. Then, consuming drinks or foods containing caffeine (coffee, tea, etc.) reduces the absorption of iron. It is best to take these last 2 hours before or after iron-rich meals or snacks (Montreal Diet Dispensary, 2011). Usually, it is not necessary to take an iron or vitamin C supplement. If you already have anemia, the iron supplement will be necessary and of course a doctor should be involved. Ideally, a dietitian will also be involved.
On the other hand, vitamin B12 is found in fortified vegetable drinks, nutritional yeast (Vegetarian Association of Montreal, 2019) and certain fortified cereals (NHS). Since the sources are very limited in a vegan diet, it is possible that a vitamin B12 supplement is advised. For more information, you can contact me or another nutritionist.
Calcium and Vitamin D
On the other hand, in keeping our bones and teeth healthy, calcium and vitamin D play very important roles.
Sources of calcium: soy products (fortified soy beverage & firm and extra firm tofu), fortified drinks (rice, nuts, oats, etc.), sesame butter (tahini), white beans, broccoli, bok choy, almonds ( Health Canada) and supplements.
Sources of vitamin D: fortified drinks (soy, rice, nuts, oats, etc.), fortified margarines, exposure to sunlight and supplements.
This mineral helps in many aspects of our cellular metabolism. It plays a role in our immune function, in synthesizing our proteins, in healing wounds, in our DNA synthesis and more.
Sources of zinc: pumpkin seeds, nuts (almonds, cashews), chickpeas, kidney beans, green peas and oats (National Institutes of Health, 2021), tofu, tempeh, lentils, black beans, quinoa (Healthline), etc.
Protein is a macronutrient that gives you energy. It is used for the development and maintenance of our tissues, helps chemical reactions in our body to occur and much more (Van De Walle, G., 2018).
The quality of plant-based protein varies, but a person following a vegan diet can easily meet their protein needs with adequate calories and a variety of high-protein plant foods. If we only consume plant-based protein during a day, it is important to vary our sources to meet our nutritional needs. You can find more information on this by clicking on this link.
An essential lipid is a molecule that our body cannot produce. So we have to find it in our food. This is the case with omega-3s. It is used for the structure of our cell membranes. It is also used to make other molecules in our body that have functions in our cardiovascular, pulmonary, endocrine and immune systems. In an omnivorous diet, fishes are a great source of omega-3 and obviously avoided in a vegan diet. Therefore it is essential to replace this source with other vegan sources of omega-3.
Source of Omega-3: plant oils (flax, soybean and canola seeds), chia seeds, walnuts, edamame, etc. (National Institutes of Health, 2021)
Thanks to a varied diet, it is possible to meet all our nutrient needs while following a vegan diet. The key to success is the planning of our meals. For a diet adapted to your needs and for more information, contact me. It will be my pleasure to enlighten you on this subject.
See you next time,
Karine Drouin, Registered Dietitian
Dispensaire de diététique de Montréal. (2011). Comment augmenter l’absorption du fer? Retrouvé le 14 mars 2021 au https://www.dispensaire.ca/article/augmenter-absorption-fer-supplement/
Harvard Health Publishing. (2019). Should you be taking an omega-3 supplement? Retrouvé le 19 mars 2021 au https://www.health.harvard.edu/staying-healthy/should-you-be-taking-an-omega-3-supplement
Healthline. (n.d.) Top 10 Vegan Sources of Calcium. Retrouvé le 21 mars 2021 au https://www.healthline.com/nutrition/vegan-calcium-sources#The-bottom-line
Healthline. (n.d.). Zinc: Everything You Need to Know. Retrouvé le 8 Avril 2021 au https://www.healthline.com/nutrition/zinc#sources
Les diététistes du Canada. (Mai, 2018). Ce que vous devez savoir au sujet de la vitamine B12. Retrouvé le 14 juin 2021 au https://www.unlockfood.ca/fr/Articles/Elements-nutritifs-(vitamines-et-mineraux)/Ce-que-vous-devez-savoir-au-sujet-de-la-vitamine-B12
Les diététistes du Canada. (2020). What You Need to Know About Following a Vegan Eating Plan. Retrouvé le 19 mars 2021 au https://www.unlockfood.ca/en/Articles/Vegetarian-and-Vegan-Diets/What-You-Need-to-Know-About-Following-a-Vegan-Eati.aspx
Link, R. (Juillet, 2017). The 7 Best Plant Sources of Omega-3 Fatty Acids. Retrouvé le 6 Avril 2021 au https://www.healthline.com/nutrition/7-plant-sources-of-omega-3s#TOC_TITLE_HDR_2
National Health Services (NHS). (Août, 2018). The Vegan Diet. Retrouvé le 24 mars 2021 au https://www.nhs.uk/live-well/eat-well/the-vegan-diet/
Santé Canada. (2008). Nutrient Value of Some Common Foods. Retrouvé le 24 mars 2021 au https://www.canada.ca/content/dam/hc-sc/migration/hc-sc/fn-an/alt_formats/pdf/nutrition/fiche-nutri-data/nvscf-vnqau-eng.pdf
U.S. Department of Health & Human Services. National Institutes of Health. (Mars, 2021). Omega-3 Fatty Acids. Retrouvé le 6 Avril 2021 au https://ods.od.nih.gov/factsheets/Omega3FattyAcids-HealthProfessional/
U.S. Department of Health & Human Services. National Institutes of Health. (Mars, 2021). Riboflavin. Retrouvé le 8 Avril 2021 au https://ods.od.nih.gov/factsheets/Riboflavin-HealthProfessional/
U.S. Department of Health & Human Services. National Institutes of Health. (Mars, 2021). Zinc. Retrouvé le 6 Avril 2021 au https://ods.od.nih.gov/factsheets/Zinc-HealthProfessional/
Van De Walle, G. (2018). 9 Important Functions of Protein in Your Body. Healthline. Retrouvé le 25 décembre 2020 au https://www.healthline.com/nutrition/functions-of-protein#TOC_TITLE_HDR_8