The public-relations department at Kraft sent me some samples of South Beach Diet 100-calorie cracker packs. The crackers were good, but the concept of 100-calorie snack-packs wasn't new. Still, as I nibbled I got to thinking again about portion control. I still can't believe how little you get for 100 calories. There hasn't been one occasion when I saw a prepackaged snack and thought, "Wow, look at all that." The last time I was wowed was when I did a column on fruit and found out that peaches were only 60 or so calories each.

The point is that most of us would be surprised by how little we get for our calorie buck. Research shows we underestimate how many calories we consume. In fact, we underreport the amount of food we eat by about 45 percent. One study showed that on average, junk foods were underestimated by more than 600 calories. Even registered dietitians can underestimate their caloric consumption by 16 percent.

The average person should consume 1,600 to 2,500 calories per day. (You can find your daily caloric budget at www .dietdetective.com/weight loss/caloriebudget/.)

With this in mind, I thought a little lesson in "what you get for the calories" would be helpful. There will be a quiz at the end to see how nutrition savvy you really are.

Here are a few examples of calorie values. (All exercise equivalents are based on a 155-pound person.)

WHAT YOU GET FOR ABOUT 10 CALORIES