Size Matters: Your Guide to Healthy Portion Sizes

Potato Chips

Standard size: 2 ounces
Better-for-you size: 1 ounce

Calorie difference: 154

"Snack sizes are often twice as big as they were 30 years ago," says Michael Jacobson, PhD, the executive director of the Center for Science in the Public Interest. "And even though the labels on the bags may say they serve two or more, many people polish off the entire contents themselves." One of the most popular snacks, potato chips, may contribute more to long-term weight gain than many other foods or drinks: A study in the New England Journal of Medicine found that for every additional serving of chips a person consumes daily, they gain nearly two pounds every four years.

Lessen plan

Choose popped as opposed to fried chips to get more food (about 23 crisps versus 13) for fewer calories. If you prefer the classic version, opt for a one-ounce package or split a bigger bag with a buddy.