Women with repeated attempts at weight loss, even if the weight is regained, have modestly greater weight loss at an obesity management clinic than women without such a history, data suggest.
In a retrospective study of data for more than 11,000 participants in a weight-management program, the frequency of weight loss was significantly correlated with the total lifetime weight loss in men (r = 0.61, P < .0001) and women (r = 0.60, P < .0001).
“It should be harder for you to lose weight when you’re older, as opposed to younger. That’s just biology,” study author Sean Wharton, MD, PharmD, medical director of the Wharton Medical Clinic, Burlington, Ont., told this news organization. But older people “have practiced a whole lot more than younger people. That’s probably one of the big things” in their favor, he added.
Dr. Wharton also is a clinical adjunct professor at York University, Toronto, and the lead author of 2020 Canadian clinical practice guidelines on obesity.
The current data were published in Obesity.
Practice makes perfect?
The prevalence of obesity is increasing. It is uncertain whether frequent weight losses help or hinder future weight-loss attempts. The effect of age at overweight on future weight loss attempts is also unclear.
To examine these questions, the current researchers analyzed the experiences of patients with obesity treated at the Wharton Medical Clinic Weight Management Program, Hamilton, Ont. At enrollment, participants responded to a questionnaire that elicited information about basic demographics, past weight loss and health practices, medical history, and family medical history. Patients did not receive any stipend for their participation and consented to the use of their medical data for research purposes. The investigators assessed weight change through a retrospective review of electronic medical records.
The study examined a data set that included 36,124 patients who were predominantly White, middle-aged women. “Although this is reflective of the demographic that is most commonly seeking obesity management in North America, the applicability of these findings to other groups is unclear,” wrote the investigators.
As a group, women under age 40 lost 1.7 kg, while those from ages 40 to 60 lost 3.2 kg, and women older than 60 lost 4.2 kg. Weight loss among men was greater and followed a similar pattern. Men under age 40 lost 3.0 kg, those between ages 40 and 60 lost 4.2 kg, and those older than 60 lost 5.2 kg.
To examine how long participants had been trying to lose weight, the investigators analyzed their age of overweight onset. Most participants reported having become overweight before age 40 and having lost at least 4.5 kg at least once in their lifetime. Older women with a longer history of losing weight had better results during the study.
In middle-aged and older women, but not men or younger women, earlier age of overweight onset and lifetime weight loss were associated with modestly greater weight loss at the clinic. When the researchers assessed women age 60 and older, they found that those who had an age of overweight onset before age 10 lost 4.9 kg on average, while those whose age of overweight onset was between ages 20 and 39 lost 4.3 kg. Women with an age of overweight onset above 40 had a weight loss of 3.5 kg.
The finding of greater weight loss in older women who were experienced in dieting was surprising, said Dr. Wharton. It may reflect the effects of perseverance and lifestyle changes. “The other thing is that [older women] also have more time. They have more availability. They make more appointments. They have the ability to be more focused,” said Dr. Wharton.
The Wharton Medical Clinic operates within the Ontario Health Insurance Plan, and all services are provided at no charge to the patient, which may reduce the selection bias against patients with low socioeconomic status, wrote the investigators.