Weight loss may aid health even if some pounds return

People who lost weight through an intensive behavioral weight loss program saw health benefits, possibly even if they later regained some weight, according to a new analysis of more than 100 studies.

Researchers found that compared with those who did not, people who went through an intensive weight loss program registered better results for blood pressure, cholesterol and an indicator of diabetes for at least five years.

Some studies have suggested that a pattern of weight loss followed by regain may increase cardiovascular risk.

Many doctors and patients fear that regaining weight renders attempts to shed pounds "pointless," Susan A. Jebb, co-senior author of the study, said in a news release. The research appeared Tuesday in the American Heart Association journal Circulation: Cardiovascular Quality and Outcomes. "This concept has become a barrier to offering support to people to lose weight."

But Jebb, a professor of diet and population health at the University of Oxford in England, said the new work "should provide reassurance that weight loss programs are effective in controlling cardiovascular risk factors and very likely to reduce the incidence of cardiovascular disease."

People affected by obesity or who are overweight are at increased risk for high cholesterol and high blood pressure, both of which heighten risk of cardiovascular disease. They also are at risk for insulin resistance, a precursor to Type 2 diabetes. Behavioral weight loss programs can help people lose weight by encouraging lifestyle and behavior changes, such as eating healthy foods and increasing physical activity.

For the new analysis, researchers combined the results of 124 studies. They totaled more than 50,000 participants, with an average follow-up of 28 months. Participants had a body mass index of 33, which is considered obese, and a median age of 51.

Weight loss across the different studies ranged from 5 to 10 pounds on average, and weight regain averaged from about a quarter to three-fourths of a pound in a year.

Participants who lost weight through an intensive program were compared with people in a less-intensive or no program. On average, in the intensive group:

– systolic (top number) blood pressure was 1.5 mmHg lower at one year, and 0.4 mmHg lower at five years;

– the percentage of HbA1c, a protein in red blood cells used to test for diabetes, was reduced by 0.26 at both one and five years;

– the ratio of total cholesterol to HDL ("good") cholesterol was 1.5 points lower after one year and five years.

"For people with overweight or obesity issues, losing weight is an effective way to reduce the risk of Type 2 diabetes and cardiovascular disease," Jebb said.

In a preliminary finding, the decreased risk of being diagnosed with cardiovascular disease or Type 2 diabetes appeared to remain lower even after weight regain. However, few studies followed people for more than five years, and "more information is needed to confirm whether this potential benefit persists," Jebb said.

The researchers acknowledged limitations, including that research published after 2019 was not included in the review.

An accompanying editorial by Dr. Vishal N. Rao and Dr. Neha J. Pagidipati of Duke University School of Medicine in Durham, North Carolina, commended the work and emphasized that much remains to be understood about various weight loss interventions.

The editorial noted that behavioral weight loss programs constitute the backbone of weight management in clinical practice but often are resource-intensive, and emerging medication therapies are expensive.

"The present study has interesting implications for the impact of weight regain that may occur after pharmacologic therapies," they wrote. "What is still unknown is whether these temporary improvements in weight and cardiometabolic risk factors after weight loss intervention (behavioral or pharmacological) lead to long-term clinical benefit. In other words, is it better to have lost and regained than never to have lost at all?"