Athletes And The Vegan Diet: Here's What You Should Know
Game Changers, a recent Netflix special on the impact of a vegan diet, caused quite the buzz in the sports science world. While many in the science community are debunking and clarifying the research and evidence behind the film’s claims, I’m more concerned about supporting the vegan athlete with the knowledge needed to perform at the highest level. The vegan diet requires more diligent planning and attention to specific nutrient intakes than does the omnivore diet, and the demands of training and recovery have their own particular needs.
Micronutrient Considerations
The vegan diet, with its higher-than-average intake of fruits and vegetable, provides ample vitamins, minerals, and antioxidants, with a few exceptions.Vitamin B12 is found only in animal products, so vegans are not able to obtain it in sufficient amounts in their diets. As such, an estimated 50 percent of vegans are deficient in vitamin B126 and supplementation is recommended for vegan athletes.Iron carries oxygen throughout the body; so low iron can manifest as weakness, fatigue, shortness of breath on exertion, dizziness, drowsiness, and irritability.*
Athletes need approximately 1.5 times as much iron as non-athletes.And vegans probably need almost twice as much iron from their diet as non-vegans because plant-based sources of iron are absorbed more poorly than animal-based iron. Blood loss from injury and muscle damage, as well as GI bleeding associated with extreme endurance activities, further decreases the body's iron stores. But always check iron levels before assuming extra iron supplementation is needed.Zinc is an essential mineral that must be obtained in the diet or via supplementation. Zinc is vital for growth, immune function, testosterone metabolism, and numerous other functions inthe body.*
The majority of zinc in most diets comes from animal products, and although whole grains contain zinc, large intakes of whole grains are associated with a decrease in the amount of zinc absorbed because of zinc’s propensity to bind to compounds found in whole grains.Calcium, essential for optimal bone and muscle health,* is another mineral often lacking in vegan athletes because it is found primarily in dairy products, and although there are plant-based sources of calcium, compounds in these plants can inhibit calcium absorption.
Vegans consume 40-percent less calcium than non-vegans, resulting in a higher risk of bone fractures. Vegan athletes are encouraged to look for fortified milk alternatives and juices, or calcium supplements, to obtain the recommended 1,300 mg of calcium daily.Vitamin D protects a number of important functions in the body.* In addition to supporting healthy bones and muscles, it supports cardiovascular health and immune function.* Vitamin D is synthesized from exposure to sunlight and is lacking in most foods, vegan or otherwise. Because the importance of vitamin D in athletes is well established, supplementation should be considered.