Before you start the day with a bowl of granola, check the math: If you use your eyeballs to measure a portion of this crunchy cereal, then just one meal can add up to an extra 500 calories a day, says Jayne Hurley, RD, senior nutritionist at the Center for Science in the Public Interest (CSPI). Here’s how to keep an eye on common culprits (and cut them down to size).

Problem Foods
Soft drinks: One serving is 8 ounces—not even half the standard 20-ounce bottle you drink.

Ice cream: A 4-ounce serving is really the kiddie-sized cup at an ice-cream shop, Hurley says.

Soup: According to the CSPI, one can of this nourishing meal usually contains more than two servings.

Problem Solvers
Measure! A 3-ounce serving of meat is the size of a card deck; a ¼-cup serving of nuts is golf-ball sized; and 1 cup of cooked pasta is roughly the size of a baseball.

Don’t eat from the container. “You’ll work your way to the bottom,” Hurley warns.

Pre-portion. Buy individual-sized snacks, or measure servings and baggies.