Study participants given a low-calorie lunch did not make up for the lower calorie intake at other meal and snack times during the day

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If you want to lose weight without making drastic changes to your diet, eating a smaller lunch may be just the change you need to make. In fact, a very small change can make a substantial difference, especially over time.

Researchers at Cornell University monitored the food intake of 17 volunteers for five weeks. During week one, the participants ate all of their meals and snacks from a buffet. For the next two weeks, half of the volunteers chose one of six pre-packaged, commercially-available portion-controlled foods for their lunch. Each of the meals had approximately 200 calories. The other half of the group continued to eat from the buffet. All the subjects could eat whatever they wanted for the rest of the day.

After two weeks the two groups switched, with the other group eating the calorie-restricted meals at lunch, while the original calorie-restricted group returned to the free-choice buffet. The researchers regularly tracked the calorie intake of the participants.

Those who ate the pre-packaged, portion-controlled lunches consumed nearly 250 calories less on the low-calorie lunch days resulting in a loss of 1.1 pounds per person in two weeks. What is interesting is that the study participants did not make up for the lower calorie intake at other meal and snack times on the days they ate portion-controlled lunches. According to the researchers, they were able to sneak in calorie reductions without the body noticing.

David A. Levitsky, lead author of the study and professor of nutrition at Cornell, said this study contradicts the prevailing thinking that if a person creates a calorie deficit, they will make up for it later by eating more. This study showed no evidence of that.

Doctoral student Carly Pacanowski, co-author of the study, suggested that small reductions in calorie intake to compensate for the abundant food choices in our society may be a way to help prevent weight gain. Consuming portion-controlled lunches a few times a week is just one simple, inexpensive way to consume fewer calories without going on a diet. Over a year's time, such a regimen could result in the loss of at least 25 pounds.

The study will be published in the October issue of the journal Appetite.

Image: REUTERSKena Betancur.

This article originally appeared on TheDoctorWillSeeYouNow.com.

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