Menopause Live (12 November, 2012) From IMS

The repetitive loss and regain of body weight, referred to as weight cycling, appears to be a prevalent phenomenon, with an incidence ranging from 10 to 40% in Western countries. Studies have reported mixed findings on behavioral and physiological changes over successive weight loss attempts, including worse compliance and effects on body fat distribution, energy expenditure, and specific co-morbidities [1]. 

In a recently published study report by Mason and colleagues, 439 overweight, inactive, postmenopausal women were randomized to: (1) dietary weight loss with a 10% weight loss goal (n = 118); (2) moderate-to-vigorous intensity aerobic exercise for 45 min/day, 5 days/week (n = 117); (3) both dietary weight loss and exercise (n = 117); or (4) control (n = 87). Women were categorized as non-, moderate (past history of three episodes of weight losses of ≥ 4.5 kg), or severe cyclers (past history of three episodes of weight losses of ≥ 9.1 kg). Moderate (n = 103) and severe (n = 77) cyclers were heavier and had less favorable metabolic profiles than non-cyclers at baseline. Mason and colleagues concluded that a history of weight cycling does not impede successful participation in lifestyle interventions or alter the benefits of diet and/or exercise on body composition and metabolic outcomes [1].

Comment

The prevalence of obesity has reached epidemic proportions in many parts of the world. Obese and overweight women are constantly striving to attain ideal weight and, in the process, many of them go through weight cycles. Although some studies have reported an adverse effect of weight cycling on body composition and chronic disease risk, there has been no mechanism postulated to explain this phenomenon, nor have larger studies substantiated this. 

The association of weight cycling with death was examined among 55,983 men and 66,655 women in the Cancer Prevention Study II Nutrition Cohort from 1992 to 2008. A weight cycle was defined as an intentional loss of 10 or more pounds (≥ 4.5 kg), followed by regain of that weight. Their results did not support an increased risk of mortality associated with weight cycling [2]. The same authors have also studied the effect of weight cycling on risk of endometrial cancer and have found no increase in risk [3].

Although weight cycling may have some effect on disease risk, the serious health problems resulting from obesity are clearly understood. So it is important that women are encouraged to lose weight by a combination of calorie restriction and moderate exercise. As the National Task Force on Prevention and Treatment of Obesity had concluded two decades ago, obese individuals should not allow concerns about hazards of weight cycling to deter them from efforts to control their body weight [4].

Jyothi Unni
Jehangir Hospital, Pune, India

References

1. Mason C, Foster-Schubert KE, Imayama I, et al. History of weight cycling does not impede future weight loss or metabolic improvements in postmenopausal women. Metabolism 2012 Aug 13. Epub ahead of print
http://www.ncbi.nlm.nih.gov/pubmed/22898251
2. Stevens VL, Jacobs EJ, Sun J, et al. Weight cycling and mortality in a large prospective US study. Am J Epidemiol 2012;175:785-92.
http://www.ncbi.nlm.nih.gov/pubmed/22287640
3. Stevens VL, Jacobs EJ, Sun J, et al. Weight cycling and risk of endometrial cancer. Cancer Epidemiol Biomarkers Prev 2012;21:747-52.
http://www.ncbi.nlm.nih.gov/pubmed/22362825
4. Weight cycling. National Task Force on the Prevention and Treatment of Obesity. JAMA 1994;272:1196-202.
http://www.ncbi.nlm.nih.gov/pubmed/7741844