A systematic review published in Circulation: Cardiovascular Quality and Outcomes found that participating in an intensive behavioral weight loss program and making lifestyle changes can lead to a decrease in risk factors for cardiovascular disease (CVD) and type 2 diabetes (T2D) for at least 5 years, even if the weight is regained. According to Susan Jebb, PhD, a professor of diet and population health at the University of Oxford, this concept has become a barrier to offering support to individuals who need to lose weight. Losing weight is an effective way to reduce the risk of T2D and CVD for those who have overweight or obesity issues.
The study analyzed the results of international scientific studies updated no later than 2019, comparing risk factors for CVD and T2D among individuals who followed an intensive behavioral weight loss program to those who followed a less-intensive or no weight loss program. The analysis included different diet and/or exercise interventions, intermittent fasting, partial or total meal replacement, or financial incentives that were affected by weight loss, and took place in various settings, including app-based, in person, and telephone.
The combined results of 124 studies, which involved more than 50,000 individuals with an average follow-up of 28 months, were used to estimate changes in risk factors for CVD and T2D after weight loss. The average weight loss ranged from 5 to 10 pounds, with an average weight gain of 0.26 to 0.7 pounds per year. The investigators found that those who participated in an intensive weight loss program and lost weight had lower risk factors for CVD and T2D that lasted for at least 5 years after the program ended.
The results showed that the systolic blood pressure averaged 1.5 mm Hg lower at 1 year and 0.4 mm Hg lower at 5 years after participation in an intensive weight loss program. Additionally, the percentage of hemoglobin A1c was reduced by 0.26 at both 1 and 5 years after participation, and the ratio of total cholesterol to high-density lipoprotein cholesterol was 1.5 points lower at 1 and 5 years after participation.
Most trials look at whether new treatments are effective and focus on weight change in the short-term rather than the effect on later disease. Individual studies are often too small to detect differences between groups in the incidence of cardiovascular conditions because, fortunately, they affect only a small proportion of the whole group, and studies may not continue long enough to see the effects on ‘hard’ outcomes, such as a new diagnosis of type 2 diabetes or a heart attack.
Susan Jebb, PhD, a professor of diet and population health at the University of Oxford in the United Kingdom.