There's no set age when it's "OK" for a child to begin a vegan approach. Typically, mothers should breastfeed for four to six months, but once a baby begins solid foods, it's appropriate to replace meat products with mashed or pureed tofu or beans, along with soy yogurt and cheese, Johnson says. Still, parents and doctors should monitor growth to make sure vegan kids are getting sufficient calories and protein.
A vegan approach doesn't have to be all or nothing, either: "You don't have to adopt it 100 percent," Tallmadge says. "Even if you're close to it and you still get small amounts of animal products, you're still making a huge difference in the world, the environment, the lives of animals, and your own nutrition and health."