July 12, 2010 -- Losing weight may help modestly reduce hot flashes in menopausal women, researchers say.
Hot flashes, also known as hot flushes, are common in menopausal women. They typically cause sweatiness and redness in the face and can be disruptive and last for five or more years. Past research suggests that a higher body mass index (BMI) -- a measurement of height and weight -- is associated with more severe hot flashes, but whether losing weight could make a difference has remained unclear.
Study author Alison J. Huang, MD, of the University of California at San Francisco and colleagues randomly assigned 338 overweight or obese women to either an intense, behavior-oriented weight loss program or to a health education program. The women were taking part in a study on urinary incontinence. Participants in the intensive weight loss program had a goal to lose 7% to 9% of their body weight in 6 months. They met with experts weekly and were encouraged to exercise for 200 minutes per week, such as brisk walking, and follow a 1,200 to 1,500 daily calorie diet. The health education program required women to attend four one-hour sessions that addressed nutrition and healthy living.
The women’s average age was 53, they had a BMI of 25 or higher, and had urinary incontinence. At the beginning of the study, 154 women reported that they were bothered by hot flashes. Among this group, a total of 141 provided data about their hot flash symptoms six months after the start of the study.
Sixty-five of the 141 women said they were less bothered by their hot flashes six months after participating in the weight loss program, 53 reported no change, and 23 women reported a worsening of symptoms. Compared with those in the health education program, women who were in the weight loss program and were bothered by hot flashes had more than twice the odds of reporting a measurable improvement after six months.
Improvements were associated with decreases in weight, BMI, and waist size. However, there were no significant associations between changes in flashing symptoms and exercise, calorie intake, blood pressure, and overall physical and mental function.
The findings are published in the July 12 issue of Archives of Internal Medicine.
"Among women who were at least slightly bothered by flushing at baseline, the intensive lifestyle intervention was associated with significantly greater decreases in weight, body mass index, abdominal circumference, and systolic and diastolic blood pressure relative to the control group,” Huang and her team write. "No statistically significant effect of the intervention on self-reported physical activity, total calorie intake or overall physical or mental functioning was observed. Our findings indicate that women who are overweight or obese and experience bothersome hot flushes may also experience improvement in these symptoms after pursuing behavioral weight loss strategies; however, improvements in weight or body composition may not be the only mediators of this effect.”