Finally, research bears out what many postmenopausal women have suspected all along: Menopause can make you hungry.
For years, researchers have sought to determine whether changes in lifestyle or changes in the body are the driving force behind the sizable, and usually unwelcomed change in appetite that may accompany the end of a woman's fertility. Researchers at Oregon Health and Science University in Portland have found that plummeting ovarian hormones may account for the 12 percent jump in the number of women who are overweight in midlife compared to women in their 20s and 30s.
For most women, menopause sets in between the ages of 45 and 55. The body stops producing eggs and diminishes the production of estrogen and progesterone, dominant hormones related to a woman's reproductive system.
To assess the effects of diminished estrogen and progesterone secretion on appetite, researchers studied hunger levels in monkeys with blunted sex-hormone production. Their conclusions, presented at the annual meeting of the Society for Neuroscience, revealed plunging hormones caused the otherwise healthy monkeys to increase their food intake by 67 percent, resulting in significant and rapid weight gain. By the end of the six-week study, the chubby primates averaged an increase of 5 percent in body weight.
Lead researcher Judy Cameron, a professor of obstetrics and gynecology at Oregon Health and Science University, believes this study has profound implications for women approaching midlife because from a reproductive perspective, monkeys and humans are virtually identical.
The study also found that just as some women sail through midlife without gaining an ounce, there were a few lucky monkeys in the study. "Some animals ate considerably more, but didn't gain weight, while others gained quite a bit," says Cameron. She speculates that estrogen affects not only food intake but perhaps metabolism and activity level, as well.
Unlike appetite, activity and metabolism are two factors women can at least partially control through regular exercise, especially weight or resistance training. Women not only have to make up for a greater appetite, they must also contend with a body that burns fewer calories than it did years before. Even thin women aren't immune to this: Studies have shown that women of all sizes are likely to gain weight during menopausal years.
"With menopause and advancing age, women lose muscle mass," says Cynthia K. Sites, an associate professor of obstetrics and gynecology at the University of Vermont in Burlington. "Muscle is metabolically active tissue and burns more calories at rest than does fat, so when muscle is lost, metabolism slows."
Battling postmenopausal weight gain takes plenty of effort, but it is possible, says Cameron. The standard weight-loss advice applies here, including eating food that is high in fiber and low in calories, as well as watching portion size. Boosting exercise and paying close attention to eating habits can be enough to stave off some of the extra pounds.
A report in the Journal of the American Medical Association found that American women are putting on extra pounds much earlier and faster than did women of previous generations.