Soy milk is the closest equivalent to cow's milk, Sylvia North, New Zealand-based registered dietitian, told Insider.
It's high in protein, contains essential amino acids, and is often fortified with calcium for bone health.
Soy milk is also a good post-workout option because of its protein content, according to Smith. It contains 8 grams per cup — the same as cow's milk — and is considered a heart-healthy food for those at risk of cardiovascular diseases.