Los Angeles Times

If there’s no caramel cheesecake, you’re not likely to eat any. But plop one down on a table among a group of friends, and the forks come out. That’s a simple scene that embodies some of the complex mechanisms that make it so hard for people to lose weight and keep it off.

English researchers trying to sort out what tempts dieters and what makes them give in to temptation looked at a group of 80 people, mostly women, over seven days, giving them phones and apps to record instances of temptation: how they felt, what was happening and whether they took a bite or a sip. Over the week, they recorded 898 instances of temptation.

Some of the factors these researchers reported recently were no surprise: Being around friends, late-night cravings and alcohol have a major effect. Another factor include being tired. Who hasn’t stopped at the supermarket after a long day and bought foods they might better have left on the shelf?

But while some of those might seem obvious, the researchers are looking at exactly what’s going on. Would it help, for example, if you had a phone app to record your feelings every time you happened upon a bowl of chips?

“The findings help piece together the complex jigsaw surrounding the daily predictions of dietary temptations and help us to better understand how dietary temptations and lapses operate,” the researchers wrote in the journal Annals of Behavioral Medicine.

British dietitians have ranked lack of willpower as more important to the development of obesity than genetics, the researchers said.

The 80 participants were part of a weight-loss group or were dieting on their own. For a week, they were asked to fill out a phone diary each time they were tempted.

Participants gave into temptation a little more than half the time, according to their diaries. They were vulnerable at night and more likely to have an alcoholic drink than a sugary snack.

One thing that appeared to help dieters was an ability to focus on long-term goals.

No surprise, they reported they were more aware of their eating because they were carrying around the phones. And one of the limits of the work will surely ring true with dieters: The study was just seven days long. What happened on the eighth day?