A dietitian specializing in sports nutrition can give advice about whether someone like your son can securely switch to a vegan, plant-based diet, and the best way to do that.
You can find the names of registered sports dietitians at the Academy of Nutrition.
Vegan athletes do need to be active about consuming sufficient protein, said Nancy Clark, a sports nutrition expert and the author of “Nancy Clark’s Sports Nutrition Guidebook.” Plants, seeds and soy supply protein but in a form that is less absorbable than protein from meat. So “you need to eat a lot of it,” Clark said. “I have clients who say, ‘Oh, I put a few chickpeas in my salad.’ That’s not going to do it. You should eat cupful of chickpeas.”
Vegan athletes also may require supplements of B12, a vitamin found only in meat, and possibly of calcium, she said, especially if they are young and growing.
Interestingly, football players sometimes shy away from vegan diets because it is hard to eat enough plant-based calories to add bulk. So you, your son and his coach might wish to take into account whether he wants to be the most willowy player on the field and synthesize his diet accordingly
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