Nonfat means containing little or no fat. When you see nonfat on a milk carton or yogurt container, it tells you that nearly all the fat has been removed. Nonfat milk, also called skim milk, looks thinner and more watery than whole milk because the creamy fat that normally rises to the top has been skimmed off.

Fat is one of the nutrients in food that gives flavor and a smooth, rich texture. When fat is removed to make something nonfat, the taste and feel often change. Nonfat yogurt tastes tangier and less creamy than regular yogurt. Nonfat cheese melts differently than regular cheese.

People choose nonfat foods for different reasons. Some prefer the lighter taste. Others want fewer calories or are following their doctor's advice about their diet. But nonfat doesn't always mean healthier: sometimes manufacturers add extra sugar to nonfat foods to make up for the flavor lost when fat was removed.

The opposite of nonfat is full-fat or whole, like whole milk, which contains all its natural fat.