Researchers at University of Birmingham in the UK have just confirmed everything you already knew deep down in your heart: It's your friends' fault! According to their new study, being with your friends is one of top three temptations that might cause a dieter to cheat. The other two? Late night cravings, and duh, duh, dum... alcohol.

What makes us give in?

In the days before she founded Weight Watchers, Jean Nidetch often described herself as a fat wife with a fat husband, surrounded by fat friends. She was a classic people person who knew exactly how much her family and friends influenced her. She also wisely understood a diet just wasn’t going to work unless her friends were battling the bulge right beside her. For this reason, the very first step she took before she began the diet that changed her life (as well as the lives of thousands) was to invite her overweight friends over to her house so that they all could discuss secrets and tips for losing weight. This was the birth of Weight Watchers, an international success singled out by U.S. News & World Report four years in a row as the Best Plan for Weight Loss.

What many diets, no matter how good, often don't tell people is, What leads you to cheat? Wanting to investigate exactly which factors were most likely to cause dieters to stray from the leafy and fat-free, the team of English researchers designed an experiment that created a community record in real-time, what is known as an ecological momentary assessment. Next, the team enlisted 80 people who were either part of a weight-loss group or were dieting on their own to participate in a one-week study. Then, having been given special cell phones, participants kept an electronic diary and recorded all the temptations that came their way as well as all the situations and times when they gave in to these temptations. Finally, the researchers analyzed all the data they had collected.

What conclusions did they draw from these 80 records of cheating? Participants gave in to their temptations just over 50 percent of the time, and they were especially vulnerable in the evening. Unsurprisingly, the stronger the temptation, the more likely a participant was to lapse. Oddly, compared with either sugary snacks or overindulging on regular food, the dieters were also more likely to give in to their cravings for a good stiff drink. Plus, the participants' willpower weakened most usually when they were out with friends.

"In the fight against obesity, we need to help people become more aware of the various personal, situational, and environmental factors that expose them to dietary temptations,” Dr. Heather McKee stated in a press release. ”In doing this, we can help them to develop the necessary skills to cope successfully with dietary temptations and prevent lapses."

Following a lapse, the researchers stress the importance of bolstering a dieter’s belief in her or his own ability to reach a weight-loss goals. Or, in the language of Weight Watchers: Refocus. Reenergize. Stay Inspired. Overcome Challenges.

Source: McKee HC, Ntoumanis N, Taylor IM. An Ecological Momentary Assessment of Lapse Occurrences in Dieters. Annals of Behavioral Medicine. 2014.