Attempting Weight Loss Linked to Reduced Risk of Death

IRP Research Overturns Common Concerns About ‘Weight Cycling’

Tuesday, December 8, 2020

man chopping vegetables in his kitchen

New IRP research suggests that repeatedly losing and regaining weight is better for health than never losing weight at all. Image source: UConn Rudd Center for Food Policy & Obesity

With 2021 less than a month away, many of the more than 200 million Americans who are overweight or obese are beginning to consider making weight loss their New Year’s resolutions — perhaps not for the first time. While trying to lose weight only to ultimately regain it may be disappointing, a new IRP study suggests that repeated attempts at weight loss significantly reduce a person’s risk of dying.1

Many individuals who lose weight gain some or all of it back within a few years. Recent studies put that figure between 65 and 80 percent,2,3 odds that might be less than encouraging for individuals who want to lose weight to improve their health. Add in studies that suggest there are health risks associated with so-called ‘weight cycling’ — repeatedly losing and gaining significant amounts of weight — and it’s enough to make anyone give up before even getting started.

“There’s this idea in the scientific literature that weight cycling is bad,” says IRP senior investigator Sonja Berndt, Pharm.D., Ph.D. “As a result, doctors often are not sure what to advise their patients, and the patients start to think, ‘Why should I even attempt to lose weight, since I’ll just gain it back again?’”

However, some scientists, including Dr. Berndt, are skeptical of past studies that link weight cycling to an increased risk of dying. Many of those studies did not take into account whether the participants’ weight loss was intentional, a significant methodological shortcoming because many people who are ill — and therefore more likely to die — lose weight without trying to. Some past research also failed to take into account other factors associated with weight changes, such as a person’s starting weight and health-related behaviors like smoking.

women exercising on treadmill

The habits required for weight loss, such as exercising and eating more healthfully, likely explain the health benefits of repeatedly attempting to lose weight. Image source: UConn Rudd Center for Food Policy & Obesity.

In an attempt to improve on past studies, a team of IRP scientists led by Dr. Berndt analyzed data from more than 100,000 men and 61,000 women to determine the relationship between the number of times a person has tried to lose weight and his or her odds of dying from any cause. Contrary to studies claiming that weight cycling is bad for health, the IRP researchers found that the more times a person purposefully lost at least five pounds over a 20-year period, the less likely he or she was to die during the follow-up period, even if that person regained the lost weight. In other words, repeatedly losing and re-gaining weight was better than giving up after one or two attempts or, worse still, never trying to lose weight at all.

“These people who are attempting weight loss many times are likely engaging in lifestyle changes that are beneficial for them,” Dr. Berndt explains. “Maybe they’re eating healthier foods or maybe they’re exercising more during each of these weight loss attempts, and over time those benefits accumulate because they have more time during which they are engaging in healthy behaviors. Even if they were not successful at losing weight, because they were engaging in these healthy behaviors, they saw a benefit.”

The IRP researchers saw the same relationship between attempted weight loss and a reduced risk of death regardless of participants’ starting weight, and they also observed a trend suggesting that more weight loss attempts might decrease the risk of dying from cancer and cardiovascular disease in particular. In addition, among a subset of individuals who had never tried to lose weight, those who lost weight unintentionally were more likely to die than those who maintained their weight or gained weight, lending support to the idea that it is important for studies to differentiate between deliberate and unintentional weight loss.

Dr. Sonja Berndt

Dr. Sonja Berndt

Interestingly, the study also found that people who lost 100 pounds or more in total over the 20-year period were less likely to die if they lost the weight over many smaller attempts but not if they lost all the weight in a few large efforts. This suggests that going to extreme measures to drop large amounts of weight all at once may not be an effective strategy.

Unfortunately, the IRP researchers lacked more detailed data about the methods the participants’ used to lose weight, limiting their ability to draw broad conclusions about what strategies might be most effective. Future studies that collect that sort of data and gather information from participants more frequently could produce important insights into how people should go about losing weight. Regardless of the details, though, the IRP study suggests that weight cycling is not as problematic as past research made it seem.

“The more you try, the better — that’s our take home message,” Dr. Berndt says. “If you’re overweight or obese, you shouldn’t think, ‘I tried once and I failed, so I’m not going to try again.’ It’s still good to try even if you fail.”

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References:

[1] Increased frequency of intentional weight loss associated with reduced mortality: a prospective cohort analysis. Willis EA, Huang W, Saint-Maurice PF, Leitzmann MF, Salerno EA, Matthews CE, Berndt SI. BMC Med. 2020 Sep 17;18:248. doi: 10.1186/s12916-020-01716-5.

[2] Long-term weight loss maintenance. Wing RR, Phelan S. Am J Clin Nutr. 2005 Jul; 82 (1 Suppl):222S-225S. doi:10.1093/ajcn/82.1.222S.

[3] Long-term weight loss maintenance in the United States. Kraschnewski JL, Boan J, Esposito J, Sherwood NE, Lehman EB, Kephart DK, Sciamanna CN. Int J Obes (Lond). 2010 Nov;34(11):1644-54. doi: 10.1038/ijo.2010.94.

Category: Science