Weekend May Derail Your Diet, Study Finds

Whether it's working out during the week or ticking off calories and fat grams, many of us try to do our due diligence. However, for some of us -- once the clock strikes 5 p.m. on Friday -- all bets are off.

According to a study published in the Fall 2009 issue of the Journal of Public Policy & Marketing, some of us consume up to 400 more calories during the weekend. Keep up that streak weekend after weekend, and you're looking at almost 21,000 extra calories per year, which equates to nearly six extra pounds. Yikes!

Researchers attribute weekend over-eating to simply having more time to eat, especially during breakfast, as well as for overcompensating after a light meal by indulging with the next.

J. Jeffrey Inman, professor of marketing at the University of Pittsburgh, and Adwait Khare of Quinnipiac University, analyzed data from 600 individuals, who tracked their eating habits as part of a survey used for American food companies. Twelve percent of the participants consumed nearly 400 extra calories.

The good news is that 35 percent of people only consumed an extra 37 calories during the weekend, and some even decreased calorie consumption. Twelve percent of participants who ate more during breakfast, lunch and dinner racked in an extra 400 calories.

"It's possible that people [who consumed 400 more calories on the weekend] have a very busy weekly schedule," said Khare. "It's a chance to unwind, relax and really enjoy their food. There is also a social aspect to eating [on the weekend,] and socialization increases consumption."

Although an extra 37 calories seems to pale in comparison to 400, keep in mind that we're working with 52 weeks in a year, and even those calories can result in almost 2,000 extra calories per year, which equates just over half a pound.

"These small things add up," said Khare. "The impact is much more than what the weekend can seem like. For many people, it can be a significant increase."

However, other research has found that having an off day from a diet can help you stay on track and feel emotionally satiated. If you do have a cheat day in your diet, make sure it's not an all-out binge.

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