It’s no secret that excess weight is a killer. Overweight and obese people are at increased risk for high cholesterol and high blood pressure, two factors that increase risk of cardiovascular disease, and insulin resistance, a precursor to type 2 diabetes. Globally, excess weight contributed to 2.4 million deaths in 2020, according to the American Heart Association’s 2023 statistical update.
Intensive weight loss programs can help people lose and maintain a healthy weight by encouraging lifestyle and behavior changes, such as eating healthy foods and increasing physical activity. Unfortunately, it’s common for participants to regain some weight after participating in such programs. And some observational studies have suggested that this pattern of weight loss followed by weight regain could increase cardiovascular risk.
However, a new research review published in Circulation: Cardiovascular Quality and Outcomes disputes that notion, finding that weight loss was associated with a five-year decrease in risk factors for cardiovascular disease and type-2 diabetes—even if some of that weight was regained.
For this review, researchers examined the results of 124 different studies that followed more than 50,000 participants, with an average follow-up of 28 months. Studies in the analysis included diet and/or exercise interventions, partial or total meal replacement, intermittent fasting, or financial incentives contingent on weight loss. The studies took place in a variety of settings, including in-person, app-based, and over the phone.
Researchers used the combined results of the studies to estimate changes in risk factors for cardiovascular disease and Type 2 diabetes after weight loss. The average weight loss across the different studies ranged from 5 to 10 pounds, while weight regain averaged 0.26 pounds to 0.7 pounds a year. Participants were an average age of 51, with a body mass index of 33, which is considered obese.
After analyzing the results, the researchers found that, compared to people in less intensive programs and those in no weight loss programs, participants who lost weight through an intensive weight loss program had lower risk factors for cardiovascular disease and Type 2 diabetes. These lower risk factors lasted for at least five years after the weight loss program ended:
- Systolic blood pressure was 1.5 mm Hg lower at one year, and 0.4 mm Hg lower at five years after participation in an intensive weight loss program.
- 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 good (HDL) cholesterol was 1.5 points lower at both one year and five years.
The results also showed that a decreased risk of being diagnosed with cardiovascular disease or type 2 diabetes appeared to remain lower even after weight regain. However, few of the reviewed studies followed people for more than 5 years, so the study authors noted that more research is needed to determine whether this benefit persists.
“Many doctors and patients recognize that weight loss is often followed by weight regain, and they fear that this renders an attempt to lose weight pointless,” says study co-senior author Susan A. Jebb, PhD, of the University of Oxford in the United Kingdom. “Our findings should provide reassurance that weight loss programs are effective in controlling cardiovascular risk factors and very likely to reduce the incidence of cardiovascular disease,” she said.
While encouraging, the results of this review are far from definitive. As an editorial accompanying the review notes, “The present study has interesting implications for the impact of weight regain that may occur after pharmacologic therapies,” they write. “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?”