Long-term weight loss effects on all cause mortality in overweight/obese populations

Abstract

This systematic review assesses the long-term effectiveness of weight loss on all cause mortality in overweight/obese people. Medline, Embase and Cinahl were searched (1966–2005). Cohort studies and trials on participants with Body Mass Index ¡Ý25 kg/m2, with weight change and mortality with ¡Ý 2 years follow-up were included finally identifying 11 papers based on 8 studies. There may be gender differences in the benefits for all cause mortality. The impact of weight loss in men on mortality was not clear with some studies indicating weight loss to be detrimental, while a recent cohort study showed benefits, if it were a personal decision. Other studies with no gender separation had similarly mixed results. However, one study indicated that overweight/obese women with obesity related illness, who lost weight intentionally within one year, had significantly reduced mortality rates of 19% -25%. In contrast, studies of overweight/obese diabetics irrespective of gender, showed significant benefit of intentional weight loss on mortality in a metaanalysis, HR=0.75(0.67- 0.83). There is some evidence that intentional weight loss has long-term benefits on all cause mortality for women and more so for diabetics. Long-term effects especially for men are not clear and need further investigation.National Health Service (NHS) R&D Health Technology Assessment Board