Can Triathletes Be Vegan?

February 02, 2017

What is a Vegan Diet?

A vegan diet is one in which animal products including meat, fish, egg, dairy and derivatives are totally avoided. Some vegans will also avoid other non-plant products such as honey.  The reasons for becoming vegan range from being environmentally-friendly, doing less damage to the animal community and doing it for personal/health reasons.

People embracing the vegan diet are at low risk of heart disease and cancer because of the very high intake of fruits and veggies and lower intake of saturated fats (from meat and dairy). Furthermore, having a diet favouring legumes, nuts, seeds and whole grains over processed foods will favour a healthy digestive system and diminish the risk for chronic diseases. The benefits conferred by this diet do not seem to come from the avoidance of animal products, but from the higher intake of phytochemical, fibre, antioxidants and vitamins.

Is a Vegan Diet Suitable for Endurance Athletes?

This diet is suitable for endurance athletes since it is a high-carbohydrate diet (fruits, veggies, legumes, whole grains). Athletes embracing the vegan diet are also low consumers of food additives, sugary foods and processed foods, which make these vegan people even healthier. According to a recent case-study of a vegan triathlete from the University of Witten in Germany, cardiac output and respiration are supporting the demand of the body and the vegan athlete is able to demonstrate a high performance on a long-continuous distance. There is no proven difference that the omnivorous triathlete performs better than his vegan competitor.

Protein Sources:

Protein sources in the vegan diet are numerous: beans, nuts, seeds, tofu, tempeh, meat analogues, whole grains. These protein sources are often called "incomplete" (except from soybeans and quinoa). On their own they do not contain all the essential amino acids needed by the body compared to meat or milk that are considered "complete". However, one must know that over the course of the day, the body will be able to get all the essential amino acids from different plant-protein sources. In fact, pairing of different protein sources is needed but not necessarily at each meal. Planning is vital for the athlete to make sure the number of grams of protein needed to sustain the training is met.


Individuals consuming a vegan diet could be at risk of iron deficiency.

Vegans can also be at risk of zinc and calcium deficiencies, but these are uncommon if your diet is well balanced. 

Vitamin B-12 is not found in fruits, vegetables, legumes, nuts nor grain products. Vitamin B-12 comes from animal products. Therefore, vegans have to find a way to add it to their diet. Symptoms of vitamin B-12 deficiency include anemia, fatigue, poor digestion, poor focus and concentration. In the long term, a diet poor in B-12 can lead to dementia, stroke and poor bone density. To avoid this situation, look for B-12 enriched foods (such as enriched non-milk beverage and enriched nutritional yeast) at your grocery store or take supplements if needed. The majority of vegans need to take the supplement (RDA 6 µg) in order to decrease the risk of heart disease and pregnancy complications.

Overall, the vegan diet can provide significant health benefits when adequately consumed. To ensure right energy intake, nutritional adequacy and diversity among vegan options, meet with a dietitian!


Marina Parent

Dietitian-nutritionist, dtp.




Leischik, R., & Spelsberg, N. (2014). Vegan Triple Ironman. Case-Reports in Cardiology, 1-4.

Vesanto , M., Winston, C., & Levine, S. (2016, December). Position of the Academy of Nutrition and Dietetics: Vegetarian Diets. Journal of the Academy of Nutrition and Dietetics, 116(12), 1970-1980.

Photo Credit: Freepik


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