Overweight women who suffer from bothersome hot flashes may find some relief by losing some weight, hints a new study published today.

In the study, women who participated in a program that encouraged them to exercise more and eat less improved their hot flashes more that a group with little weight-loss coaching.

“We’re pretty excited to have this evidence that ... women who lose weight can improve their symptoms,” study chief Dr. Alison Huang of the University of California, San Francisco, told Reuters Health.

At least 2 out of 3 women in the United States suffer from hot flashes at some point during menopause, and studies have shown that heavier women get more severe and more frequent hot flashes, Huang and colleagues note in the Archives of Internal Medicine.

Huang and her colleagues followed a group of 338 overweight and obese women who were participating in a study for women with incontinence - which is not related to menopause symptoms, Huang said, and so shouldn’t have affected the results.

Two-thirds of the women were put through a program that educated them on healthy weight-loss strategies. They were also given meal plans and coupons for Slim-Fast products and were told to record their daily exercise.

The other group went to a few educational sessions on weight loss and health.

About half of the women in both groups started the study complaining of hot flashes. At the beginning of the study and again after six months, these women were weighed and measured and they filled out questionnaires about their eating and exercise habits and about their recent hot flash symptoms.

Women in the weight-loss program dropped an average of more than 16 pounds and cut more than 2 inches off their waistlines over the six months, compared to about 4 pounds and 1 inch in the other group. And women who shed more pounds and waistline inches reported greater improvement in their hot flash symptoms.

Almost half of women who got intensive weight-loss coaching saw improvements in their hot flashes, whereas 12 percent said their hot flashes got worse. In women without the intervention, 40 percent got better and a quarter reported worse symptoms.

The authors measured symptoms as “slightly,” “moderately,” “quite a bit,” and “extremely” bothersome, and most women who reported better or worse symptoms moved over one category over the course of the study.

Scientists still don’t know precisely what causes hot flashes, Huang said. Hot flashes are likely related to hormonal changes - particularly the fall in estrogen levels - that happen during menopause. “For all women (in menopause), the estrogen levels go down and stay down,” she noted, but not all women suffer from hot flashes.

It’s also unclear why overweight women seem to suffer more from hot flashes than their slimmer peers, the investigators note in the Archives of Internal Medicine. It could be a result of “insulation” from the extra fat itself, or hot flashes could be related to lifestyle differences between overweight and non-overweight people, they suggest.

Hot flashes can be relieved with hormone therapy. But Huang said widely-publicized reports linking hormone therapy to an increased risk of heart disease and breast and ovarian cancer in some women have left many women “very reluctant to take hormone therapy. That has really left a big hole in our treatment regimen.”

That’s why weight loss as a way of controlling symptoms is so appealing, Huang said.

And while women with the best results in the study had the help of diet and exercise coaches to encourage them in their weight-loss efforts, Huang said that dropping even a few pounds could help overweight women improve their hot flashes.

“We hope what this study will do is help give women some motivation if they’re overweight ... that the efforts that they make through diet and exercise can have immediate benefits,” she said.

The study was funded by government grants. Some of the authors also receive grant money from pharmaceutical companies.

SOURCE: Archives of Internal Medicine, online July 12, 2010.