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Lots of foods contain protein, even vegetables While a carrot doesn't give you much, a piece of chicken is loaded with protein Between the two extremes are more plant-based proteins Besides chicken, a weight lifter could opt for beef, turkey, whey, or pork What is the best source of protein for a body builder: are animals still on top of the food chain Hard Science Proteins have been explored and explained by scientists in order to determine their levels of Branched Chain Amino Acids
