Lose weight: Year after year, it’s America’s No. 1 resolution. Maybe it’s yours.

But, as you probably know all too well, most weight-loss resolutions end up broken. Research from the University of Scranton suggests that one-third of people who ring in the New Year with resolutions throw in the towel by February. Meanwhile, a quarter of resolvers don’t even make it a full week. But experts say that perhaps willpower isn’t the problem. Making a resolution to lose weight in the first place is.

Why is weight-loss a bad resolution?

“A lot of people in the health and wellness industry have known this for a long time – that diets and resolutions to lose weight don’t work for the vast majority of people,” says Michelle May, M.D., physician and author of Eat What You Love, Love What You Eat. “Rather, dieting or focusing on weight loss leads to weight cycling and long-term weight gain.”

For instance, research from Traci Mann, currently the principal investigator at the University of Minnesota’s Health and Eating Lab, shows that while most people can lose about 5 to 10 percent of their starting weight on any given diet, they actually end up gaining more weight than what they originally lost. And, get this: Mann says these people would be healthier in the long term if they just maintained their weight, versus stressed their body with yo-yo dieting.

What’s more, one International Journal of Obesity study of more than 2,000 sets of twins found that twins who intentionally tried to lose weight just one time in their lives were about two to three times more likely to become overweight in the future, compared to their genetically identical, non-dieting counterparts. Plus, the more often one twin tried to lose weight, the greater his or her risk of subsequent weight gain.

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“Unfortunately, when people gain back the weight, they think it’s just them. They think the diet worked because they lost weight initially, but that they ultimately failed,” May says. “That couldn’t be further from the truth. The diet is what failed.”

‘The Diet Starts Tomorrow’: Bad Resolution 101

Unfortunately, when your weight-loss efforts have a start date, they more than likely also have an end date – whether they’re focused in the kitchen or the gym.

Indeed, when most people decide to lose weight, they don’t start working on it right that instant. They put it off to Jan. 1 – and overeat healthy foods and avoid exercise right up until the ball drops. The diet starts tomorrow, they say. “It’s a zero to 100 mentality that is destined to fail,” says Joseph DeBaun, training manager at DavidBartonGym Uptown in New York City.

Plus, most people just dread the concept of trying to lose weight. “People treat ‘weight loss’ as a sort of punishment for all of the times that they were ‘bad’ in the last year,” May says. That black-and-white, “I’m either being good or bad” mindset in turn makes people hyper-focused on what they “can’t” do or eat, May says. It makes weight loss feel impossible, and is associated with poor body image and disordered eating. It doesn’t make healthy living a sustainable part of one’s lifestyle, but rather a sentence to serve.

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New Year, New Approach

All possible procrastination aside, for many people, Jan. 1 can feel like a chance for a fresh start, a perfect time to make a change. So if you don’t make a resolution, what’s the right way to go about making healthy changes in the coming year?

May suggests using the time to reflect on your biggest healthy-living challenges of the past year, and think through how you might surmount them in the next one. Be mindful not to frame any new approaches as “fixes” for your mistakes, but rather as lifestyle improvements, DeBaun says.

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So maybe it’s taking post-meal walks or shopping for fresh foods more often, rather than hitting the drive-thru line. Or just getting to bed on time. Whatever changes you decide are right for you, it’s best to work on integrating them slowly. That way, they’re more likely to become habits rather than part of an unsustainable weight-loss saga. “You have to take on a much more realistic approach, and if zero is your starting point on December 31 then shoot for a 1 on Jan. 1 and build from there,” he says.

And, above all else, remember that if any of those changes aren’t something you can or want to do for the long haul, you need to find a different approach. “To make a sustainable change, the things you are thinking about doing in the New Year need to be things you can do every day for the rest of your life,” May says. That’s when healthy weight loss happens.

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