Protein is the building block on muscle and other tissues. It’s the foundation of any bodybuilding or strength development goal. But the World Health Organization has some unkind words for certain proteins. A review of evidence by 22 scientists put processed meats in the same cancer risk category as tobacco smoking and asbestos. Their findings are published in The Lancet.

In addition to high biological value protein, red meat from cattle is a good source of B vitamins, iron and zinc. Researchers determined that risk increases with consumption, so they suggest red meat should be considered a once in a while food.

True Strength Moment: A healthy, balanced diet should include a variety of whole foods, which remain in as a close to their natural state as possible. Red meat falls into this category, and it’s up to you how often to put it on the menu. Processed meats like bacon, sausage and hot dogs are a different story.