A Big Disconnect: Calories In, Calories Out

It's not shocking to hear that there's a disconnect between what Americans know about healthy eating and what we actually put in our mouths. The proof is in the pudding: Now, more than ever, Americans are fat. (In a study looking at heart disease published this week, more than 60 percent of white, Hispanic, and African-American participants between 45 and 84 were overweight, and more than 30 percent were obese. Only Chinese-Americans, of whom 33 percent are overweight and a mere 5 percent obese, bucked the trend.)

There are a host of reasons, but you can boil a lot of them down to this: We generally put away more than we burn off through daily activity and exercise. A "diet disconnect" survey released today by the International Food Information Council Foundation (a group funded by the food, beverage, and agricultural industries) found that 44 percent of those surveyed didn't balance what they ate with what they burned off. Only 15 percent knew the number of calories they needed to consume every day to maintain their weight.

That's because it's not particularly easy to figure it out. You can do some back-of-the-envelope math to estimate your resting metabolic rate—the number of calories you burn just by lying around all day—and then add in what exercise and other activity you do, but some of the RMR formulas are outdated. And that simple math can't always account for the nonexercise activity you do during the day. Here's a helpful calculator that takes into account how many hours you sleep, putz around the house, walk around without breaking a sweat, and exercise more vigorously. Put in all your info, and it will tell you how many calories, plus how many grams of carbs, fat, and protein, you should be eating each day to maintain or lose weight (you can choose a 1- or 2-pound loss per week).

Once you've got the number, you can aim for that many calories. Be careful, though, to read labels, since it's easy to underestimate the number of calories you're consuming. Here's a database of common foods.