Researchers Pinpoint Causes Of Post-Menopausal Weight Gain

Post-menopausal women tend to carry excess weight in their stomachs more than the hips and thighs, where where a woman's fat storage is usually concentrated, and a new study points to a link between proteins and estrogen as the reason why.

After menopause proteins that correspond with fat storage become more active in a woman's body, causing fat storage patterns shift. The link between estrogen and body fat storage has been well documented, but the underlying causes were poorly understood.

But new research from Dr. Sylvia Santosa at Concordia University's Department of Exercise Science sheds lights on the connection between fat storage and estrogen by examining the fat storage process at the cellular level.

Santosa, who partnered with Dr. Michael Jensen of the Mayo Clinic in Rochester, Minn., has found that the proteins that are most active in post-menopausal women the ones that correspond with fat storage.

"The fat stored on our hips and thighs, is relatively harmless," Santosa said in a statement. "But the fat stored around the abdomen is more dangerous. It has been associated with diabetes, heart disease, stroke and even some cancers. When post-menopausal women put on more abdominal fat, they dramatically increase their risk for these health problems. Given these dangers, it is very important to understand the how the lower levels of estrogen associated with menopause changes where fat is stored."

The research compared pre- and post-menopausal fat storage in 23 women with similar ages, body mass indices and body fat composition. The similarities allowed Santosa to isolate the effects of estrogen on fat absorption and storage.

The team analyzed the enzymes and proteins associated with fat storage in the thighs and abdomen and determined that the cells stored more fat after menopause than before. The changing cell structure is responsible for post-menopausal women burning less that than pre-menopausal women.

"Taken together, these changes in bodily processes may be more than a little surprising - and upsetting - for women who previously had little trouble managing their weight,"  Santosa said.

The increased cellular activity in post-menopausal women is not specific to the abdominal region, but more fat stored overall results in more abdominal fat.

"The information revealed by our study is valuable not only to post-menopausal women and their doctors, but to obesity studies more generally. A clearer picture of which proteins and enzymes increase fat storage makes those productive targets for future medical advances in the fight against obesity," Santosa said.