Menopausal weight gain presents surmountable challenge

Weight gain at menopause results from a combination of factors, including hormonal shifts, age-related metabolic changes and decreased physical activity.

Besides increased BMI, menopause can lead to changes in the distribution of body fat, prompting a shift from lower-body adiposity to abdominal adiposity. This weight gain and change in weight distribution are associated with increased risk for metabolic syndrome, type 2 diabetes and certain types of cancer.

To minimize these health risks, maintaining a normal body weight throughout life should be an important priority for all women. However, losing weight during menopause can be more challenging than earlier in life.

“Midlife and the menopause transition is a time when women typically gain weight, and losing it is difficult because there are multiple things going on,” Rebecca C. Thurston, PhD, professor of psychiatry, clinical and translational science, epidemiology and psychology at the University of Pittsburgh, told Endocrine Today. “Women’s physiology is changing, their lives are very busy, and they’re caring, oftentimes, for partners, children and aging parents, so it is a challenge.”

Mechanisms of menopausal weight gain

The average amount of weight gain during menopause is 5 lb, and 4.5 lb during 3-year follow-up, according to JoAnn V. Pinkerton, MD, FACOG, NCMP, executive director of The North American Menopause Society (NAMS) and division director of midlife health at the University of Virginia Health System.

“Weight gain is believed to be more related to aging and lifestyle changes than to menopause itself,” Pinkerton told Endocrine Today. “The difficulty with weight loss is believed to be most related to age-related changes, such as decreased metabolism and becoming less active and more sedentary. This is worsened by the fluctuations and then declines in women’s own estrogen levels.”

According to Gloria Richard-Davis, MD, FACOG, NCMP, professor and director of the division of reproductive endocrinology and infertility in the department of obstetrics and gynecology at the University of Arkansas Medical Services, estrogen synergizes with adipose tissue genes to increase subcutaneous fat in the buttocks and thighs and decrease abdominal fat deposition.

“The loss of estrogen postmenopause, independent of aging, increases total body adipose tissue and decreases lean body mass, but does not increase overall weight,” Richard-Davis told Endocrine Today. “The Study of Women’s Health Across the Nation (SWAN) revealed weight gain postmenopause, and that is highest in women who undergo surgical menopause. Additionally, racial differences were seen, with African-American women having the highest BMI.”

Risks associated with abdominal fat

The abdominal fat deposition common to menopause begins to accumulate as early as 3 to 4 years before menopause, Pinkerton said. The distribution of fat is also affected by stress and lack of physical activity.

“Hormonal fluctuations seen with perimenopause, along with metabolic changes related to aging, put women, particularly African-American women, at higher risk for metabolic syndrome, which in turn puts them at higher risk for diabetes and heart disease,” Pinkerton said.

Richard-Davis said central obesity seen in menopause correlates to increased risk for cardiovascular disease, but she added that decreases in estrogen may increase CVD risk through other mechanisms as well.

“Women’s CV risks do increase postmenopause, as we lose the protective effect of estrogen,” she said. “Estrogen has a positive effect on lipid profile, increasing HDL, which is a protective lipid, and decreasing LDL, a lipid associated with atherosclerosis.”

Obesity, hot flashes

A series of investigations conducted as part of the SWAN study, for which Thurston was an investigator, revealed correlations between weight at menopause and vasomotor symptoms.

“For many years, we believed that women who had more body fat, or who were heavier, would have fewer hot flashes,” Thurston said. “This was based on the theory that women with more body fat have more estrogen and, therefore, should have fewer hot flashes. Thus, women who are thinner should have more hot flashes. That’s called the ‘thin hypothesis.’”

Based on some hints in the literature that contradicted this hypothesis, Thurston and colleagues began to investigate it through a series of evaluations of SWAN study data. The first study was a cross-sectional analysis of data from the SWAN heart study, which explored the associations between abdominal adiposity and hot flashes in menopausal women.

“What we found was that women with more abdominal adiposity actually had more hot flashes,” Thurston said.

Earlier studies had looked solely at BMI, which does not differentiate between fat mass and lean mass, and the researchers decided next to assess total percent body fat in the full SWAN cohort.

They found that higher percent total body fat was associated with more hot flashes, Thurston said.

“Then we looked at changes in body fat over time, and we found that women who gained weight during the menopause transition were more likely to have more hot flashes at the subsequent visit,” Thurston said.

As the women from the SWAN cohort continued to age, Thurston re-evaluated them using hot flash monitors and hot flash diaries. She found that once again, findings were surprising.

“What we found was exactly the opposite of what was expected. In this study, higher body fat was associated with fewer hot flashes, as if the thin hypothesis were true,” she said. “We started wondering, what is going on here?”

This shift occurred because, in the later study, the women were substantially older and were more often past menopause, Thurston said, adding that there appears to be a modification by chronologic or ovarian aging such that for women who are younger or earlier in the menopause transition, more body fat is linked to more hot flashes, and when they are older and well past their final menstrual period, more body fat is linked to fewer hot flashes.

“Once women are older and their ovarian function has stopped, and the only source of estrogen is their body fat, we find that more body fat tends to be associated with fewer hot flashes,” Thurston said.

This "flipping" of the association between body fat and vasomotor symptoms is consistent with the pattern observed in SWAN in the associations between body fat and estradiol, Thurston said.

Earlier in the transition, heavier women have lower levels of estradiol in relation to thinner women, but in the postmenopausal phase, this association is reversed, such that women with more body fat or higher BMI have higher levels of estradiol, she said.

“Like many things in the menopause transition, it is dynamic over the course of the menopause transition,” Thurston said. “It depends on a woman’s age or menopausal stage.”

Benefits of weight loss

Thurston said she and colleagues have studied whether weight loss would, in turn, be associated with reduced hot flashes across the menopausal transition. She conducted a pilot study of 40 women and found some evidence that intentional weight loss in the perimenopausal or early postmenopause stage of the transition was helpful in reducing hot flashes.

“This was an underpowered pilot study, and we’re trying to get the full trial funded by the NIH,” she said.

Nevertheless, Thurston said, losing excess weight during and after menopause is definitely important to many aspects of overall health.

“If women are overweight or obese, they should take steps to get into that normal-weight category, for many reasons,” she said. “One is for their CV health. Obesity is such a strong risk factor for so many problems. Living a healthy lifestyle and maintaining a healthy weight not only helps women to feel better, but also makes them healthier.”

Reversing menopausal weight gain

Many methods exist for controlling weight gain or achieving weight loss, but healthy diet and exercise remain the most reliable.

“A daily caloric deficit of 400 kcal to 600 kcal, regular physical activity, low fat intake, consumption of fruits and vegetables, and ongoing behavior support all have been associated with sustained weight loss,” Pinkerton said. “The implementation of the American Heart Association’s general diet and lifestyle recommendations may decrease the risk for CV and noncardiac disease.”

Pinkerton said regular physical activity has been found to decrease the risk for breast and colon cancer, dementia, myocardial infarction, stroke, depression, loss of lean muscle mass and bone loss, all while improving immune system function.

“One study showed that just 1 hour of walking daily cut the risk for obesity by 24%,” she said. “Fewer hot flashes, fewer health risks, increased well-being — there are so many benefits to being active, whether women choose gardening, yoga, walking, biking or swimming for at least 30 minutes.”

Richard-Davis said exercise in menopause should not necessarily be exclusively focused on aerobic workouts.

“Weight-bearing exercise is especially important in menopause, both for weight and bone protection,” she said.

For women with obesity that does not respond to lifestyle changes, other options might help improve their capacity for weight loss, Pinkerton said. NAMS has reviewed some of these strategies in its clinical recommendations. Pharmacologic options include medications, such as phentermine hydrochloride, dimethylpropane, orlistat (Alli, GlaxoSmithKline; Xenical, Hoffmann-La Roche), loriciferan and phentermine/topiramate extended release.

“Decisions about these medications should be made in conjunction with a weight specialist,” Pinkerton said. “In addition, there are bariatric surgical options for weight loss for those unresponsive to medical approaches, which generally effect greater weight loss in the morbidly obese and higher rates of resolution of comorbid conditions than lifestyle or pharmacologic options.”

Hormone therapy may attenuate the abdominal adiposity associated with menopause, Pinkerton said. For many menopausal women, however, incorporating healthier habits is often sufficient to achieve weight loss and maintenance.

Physical activity and dietary modification are essential to weight loss and maintenance, Thurston said. One of her key recommendations for successful weight loss is to track all daily food intake and exercise through a food diary.

“There are many online apps and phone apps that are good for this. Work with your physician or health care provider to set a calorie goal, and track your food and exercise,” she said. “Every behavioral change we want to implement, we have to know where we’re at when we start, and we have to hold ourselves accountable.”

Thurston’s other top piece of advice is what she referred to as “stimulus control” — simply keep tempting foods out of sight.

“Keep those cookies or that candy out of your cupboard, and keep them out of your desk at work,” she said. “Don’t try to depend on willpower — willpower is a myth. You really have to keep your food environment conducive to healthy behaviors.” – by Jennifer Byrne

References:

Gold EB, et al. Menopause. 2017;doi:10.1097/GME.0000000000000723.

Shifrin JL, et al. Menopause. 2014;doi:10.1097/gme.0000000000000319.

Thurston RC, et al. Am J Epidemiol. 2009;doi:10.1093/aje/kwp203.

Thurston RC, et al. Menopause. 2008;doi:10.1097/gme.0b013e31815879cf.

Thurston RC, et al. Obstet Gynecol. 2012;doi:10.1097/AOG.0b013e31824a09ec.

For more information:

JoAnn V. Pinkerton, MD, FACOG, NCMP, can be reached at Division of Midlife Health, University of Virginia Health System, Charlottesville, VA 22908; email: pinkerton@menopause.org. Rebecca C. Thurston, PhD, can be reached at University of Pittsburg, Department of Psychiatry, Room 206, Pittsburgh, PA 151218; email: thurstonrc@upmc.edu.

Gloria Richard-Davis, MD, FACOG, NCMP, can be reached at Department of Obstetrics and Gynecology, University of Arkansas Medical Services, Freeway Clinic, 5800 W. 10th St., Little Rock, AR 72205-7199; email: garicharddavis@uams.edu.

Disclosures: Pinkerton reports receiving grants/research support and travel funds from Therapeutics Inc. (all fees to the University of Virginia). Richard-Davis reports consulting for Pfizer. Thurston reports no relevant financial disclosures.