If you are a woman heading for menopause, here’s another reason to maintain a normal weight: a recent study published in the American Journal of Epidemiology showed that women who were overweight were more likely to experience vasomotor symptoms compared to women of normal weight. The higher their percent body fat, the more likely the women were to experience hot flashes and night sweats.

This is new information; it has previously been thought that women who were heavier actually had fewer hot flashes compared to those who were thin. This is because adipose (fat) tissue, especially fat in the abdomen, produces estrogen from precursor hormones that are made in the ovary and adrenal glands.

Heavier women tend to have higher circulating levels of estrogen than thin women and these higher levels were felt to reduce a woman’s risk of hot flashes. Higher levels of estrogen have other benefits — they lower the risk of osteoporosis. On the negative side, higher circulating blood levels of estrogen in heavy women increase the risk of breast cancer and other cancers, including uterine cancer.

The majority of women in the United States experience some type of vasomotor symptoms as they move through menopause, including hot flashes and night sweats. The specific cause of these symptoms is unknown, but they are presumed to be due to changing levels of estrogen on the temperature regulation centers in the brain.

When estrogen levels drop in the brain during menopause, even in heavy women, this triggers the body to release heat, leading to a hot flash. Since body fat is more insulating than other tissues, women with more body fat probably have a harder time dissipating body heat when a hot flash comes on — hence, a more uncomfortable or more prolonged hot flash. Some studies have suggested that exercise may reduce hot flash occurrence; given the present study, it’s possible that exercise may reduce hot flashes through its impact on body fat.

So, there you have one more reason to exercise and maintain your weight as you hit the menopause. What else can help to reduce hot flashes? Reducing your intake of alcohol and hot beverages, stopping smoking and wearing loose-layered clothing are all beneficial.

Topical progesterone cream, available in health food stores, is also effective for some women. Other alternative therapies like black cohosh and red clover are sometimes helpful, but their benefits are not huge; phytoestrogens including soy have been more disappointing they tend to have a very high placebo effect. Prescription meds like Effexor, Neurontin, and Clonidine can reduce symptoms by about 50 percent, but they also have side effects.

In the end, if you’re doing everything you can to reduce your symptoms, and your quality of life, including your sleep, is compromised because of hot flashes and sweats, then estrogen may be indicated — it reduces hot flashes by about 80 percent, and more recent data has shown that the risk of hormone therapy is really pretty low for women in the early menopause.

It does not seem to increase risk of heart attack, stroke, or breast cancer in younger menopausal women and may in fact be associated with lower total mortality. The lowest dose that relieves symptoms should be used, and its use should be limited to two to three years, if possible.