Keep lunch light for easier weight loss - msnbc.com

If you've heard it once, you've heard it 4 million times: In the battle of the bulge, calories matter. Now, a new study to be published in the October issue of the journal Appetite shows just how simple cutting calories, without the hunger, can actually be.

The secret is portion-controlled meal replacements.

But you don't have to purchase one of those expensive high-fiber, or high-protein replacements touted by commercial diet groups. A cup of soup and a piece of fruit is just as good.

In their study, researchers from Cornell University measured the food intake of 17 study participants for five weeks, Monday through Friday. In week one, the group could choose foods from a lunch buffet. During weeks two and three, half of the group had to choose from six store-bought portion-controlled foods averaging about 200 calories, including a Kashi Bar, Campbell's Soup in Hand, Smucker's Uncrustables, Lean Pockets and Chef Boyardee Pasta. The participants could add an apple into the mix. At breakfast and supper, the participants could eat as much as they wanted, including two snacks during the day. In weeks four and five of the study, the remaining group followed the same portion-controlled plan.

Over the course of 10 days, all participants consumed 250 fewer calories per day, and lost a little more than one pound. None reported feeling hungry. In one year, that kind of weight loss could add up to as much as 25 pounds.

The study shows "the body is lousy at regulating energy consumption," says lead author David Levitsky, Professor of Nutritional Sciences and Psychology. What that means is that under-eating at one meal doesn't mean you're going to pig out at your next meal. And regulating calorie intake — even in relatively small increments on one day — doesn't mean you're going to overeat the next day.

When it comes to why meal replacements work, the answer is portion and calorie control, not the high fiber or protein content, according to the study authors. The researchers say you don't need to break the bank buying expensive pre-packaged marketed meal replacements. Rather, you can eat a yogurt and an apple or whatever you want from an array of readily accessible pre-packaged food items that control for calories and portion size. "The food industry has learned how to make us eat a little bit more each day," Levitsky says. "This is one little tool in the arsenal to help stop the cycle."

There's nothing magic about controlling calories only at lunch. You can do it for any meal you want, even two meals, says Madelyn Fernstrom, TODAY's diet and nutrition editor. Fernstrom is also director of the Weight Management Center at the University of Pittsburgh Medical Center.

Commercial meal replacements are expensive, but if you have the money and don't want the hassle of creating your own, don't discount them. "A meal replacement simply means you have no question about calories," she says. "So I don't care what people use, because every little bit of calorie savings adds up over time."

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