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It's usually Prevention editors testing the latest diets at our company. So we were surprised when we found out that our accounting department had challenged our human resources (HR) folks to a work diet duel.

HR accepted the challenge, a three-month weight-loss contest in which the winners (or, more appropriately, the losers) are treated to lunch on the other team's tab. Everyone weighed in, chose any diets and exercise plans they wanted to work with, and they were off.

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Downsize the Office
Diets at work just make sense.

"We spend most of our waking hours with each other," says accounting's Tom Pogash, who started the competition.

Research agrees: Work diet groups work better than solo dieting. It's convenient, and support is always a cubicle away. Plus, weight loss competitions boost morale, improve employee/manager relations, and reduce sick days and health care costs.

“I knew my co-workers were concerned about my health, and so was I," admits senior accountant Jeff Hampton, whose wake-up call came when his mom, who's also overweight, had a heart attack. "The group momentum gave me the motivation I needed to get serious about losing weight. Since we've begun, everyone—including those not competing—has helped by offering encouraging words. I'm sleeping better at night, and I have more energy."

According to Heather Rodale Stoneback, vice president of leadership development and nominated head of the HR group, "Doing this as a team is really wonderful. We all share recipes and challenges over lunch. There is no peer pressure whatsoever, just lots of support. And we laugh a lot more these days too."

More from Prevention:  7 Ways to Workout Out At Work

Pep Talks
Lunches and coffee breaks are common gathering times at work, so using them for support seems natural. "When the midafternoon munchies strike, there's always somebody around to suggest a healthy snack or a quick walk," says Pogash. (Check out these snack-free ways to boost your energy at work.)

Although everyone is doing their own thing regarding food and exercise, the diets obstacles are often the same. "I'm moderating my portions, and my coworker is doing a low-carb diet, but we both struggle with nighttime hunger and finding time to work out. It helps to talk about it at lunch," says HR coordinator Jessica Glick, who's lost six pounds.

HR director Carrie Holler agrees: "Knowing I'll check in with someone tomorrow keeps me on track tonight." She's down 10 pounds so far.

"We used to have tons of sweets, but not now," says Marian Schneck, accounting director, who's lost seven pounds. "Even nonparticipants help out by keeping our work areas free of junk food."

Results
The accounting department brought home the gold with a total loss of 133.2 pounds. Human resources lost 49.8 pounds. Both groups celebrated their diets' success with a lunch hosted by HR.

The accounting group presented HR with consolation prizes of jump ropes and handgrips. And HR gave accounting a box of beef jerky and chocolates. (A little sabotage, perhaps?)

Everyone had a fun time and agreed to make the challenge a yearly event. They all felt the work diets contest had a positive effect on their health and their waistlines.

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