Of course, people can control how they respond to their appetite, but when life gets in the way -- stress, hunger pangs, snacks in the break room -- it makes it that much harder to go against biology.
Willpower isn't a long-term strategy
Sure, ultimately you can choose to snack on baby carrots instead of potato chips, or order the kale salad instead of the bacon cheeseburger. But this weight-loss strategy only works for so long, especially if you are constantly faced with repeated temptations.
"We make hundreds of decisions every day that relate to whether I should consume something or not," Dr. Grunvald says. "You can do that for a short period of time, but just by willpower over the long term it doesn't work at all. It's a very challenging, complex problem that just doesn't work for most people."
You can only pass the free snack table at work so many times before you finally give in and grab that cookie or bag of pretzels. And when that happens, people tend to beat themselves up and wind up back at square one.
"Using self-control or willpower alone can lead to discouragement when the inevitable hiccups and setbacks happen," adds obesity medicine specialist Dr. Nitin Kumar of the Bariatric Endoscopy Institute. "If willpower is the weight-loss method, the implication is that weight gain is due to lack of willpower."