Milk is the main ingredient in cheese; cow's, goat's, and sheep's milk are most commonly used. The milk is allowed to thicken (often with the addition of rennin or rennet, and enzyme) and separate into curds and whey. The whey is drained, and the curds are used to make cheese.

Because cheese is made from milk, it's a good source of calcium. It's also high in fat and sodium. Consider the nutritional values from our chart for a one-ounce serving of certain cheeses.