February 2015 Issue

Boomer Health: Weight Gain and Menopause
Sherry Coleman Collins, MS, RDN, LD
Today's Dietitian
Vol. 17 No. 2 P. 16

What's behind the increase in unwanted pounds and what can be done about it?
As women travel through the lifecycle, their bodies naturally change in response to hormonal shifts that usher them out of the fertile phase of life. For many women, the fifth decade typically begins the season of menopause accompanied by weight gain, achy joints, muscle loss, and lack of energy. Time constraints often make it a challenge to counter these physiologic changes, since regular physical activity and eating a healthful nutrient-dense diet often take a backseat to other priorities.

Researchers say the average weight gained during menopause is a little more than 1 lb (0.5 kg) per year.1 Hormones are responsible for and affect many of the body's processes, but many people have asked, "Do hormones influence weight gain?" It's clear that the pounds begin to creep up for many women in their 50s. But is this inevitable?

With reduced calorie needs as women age, weight gain is inevitable if they don't eat healthfully and increase physical activity.2 Fewer calorie needs usually result from a decrease in physical activity, loss of lean muscle mass, and a subsequent reduction in resting energy requirements. And it doesn't take much to gain weight.
Researchers propose that significant long-term weight gain among women may be the result of eating as few as 10 extra calories per day.3

According to Julie Schwartz, MS, RDN, CSSD, LD, certified wellness coach and owner of Balanced Nutrition Coach in Tampa, Florida, many of her clients in their mid-40s are experiencing weight gain, and they blame it on perimenopause or menopause." [But] after further conversations the consistency is that most people in this age group begin to drastically decrease their purposeful, planned activity and their spontaneous activity." Schwartz says many of her clients also eat out more often and are consuming more calories.

Chris Rosenbloom, PhD, RDN, CSSD, FAND, professor emerita at Georgia State University and owner of Chris Rosenbloom Food & Nutrition Services in Atlanta, says, "Many women experience not only some weight gain, but also changes in body composition after menopause. I think some of the changes are inevitable, but lifestyle factors are huge in preventing weight gain."

The Science
Aside from reduced physical activity and dietary habits, pinpointing other reasons why women gain weight during menopause is an area of ongoing scientific investigation that has multiple hypotheses. It's documented that energy needs decrease with aging primarily because of decreased energy output.2 In a study by Brown and colleagues of more than 8,000 Australian women between ages 45 and 55, researchers found that menopause was an independent risk factor for weight gain.3 Over five years, study participants gained slightly more than 1 lb (0.5 kg) per year on average. After adjusting for biological and behavioral variables, the researchers found that, in addition to menopause, less exercise, quitting smoking, hysterectomy, and spending more time sitting all were independently associated with weight gain.3 In other research, Blanck and colleagues found that, among more than 18,500 postmenopausal women with an average weight gain of 10 lbs over seven years, both high amounts of nonoccupational sedentary behavior and lack of recreational physical activity were independent predictors of weight gain among the women.4 As a result of their research, Brown and colleagues recommended that all women going through menopause receive counsel on the potential for weight gain and ways to prevent it.3 It's possible that hormonal shifts, such as decreases in estrogen, progesterone, and testosterone, may be associated with weight gain, but these findings haven't been conclusive in human studies. In animal models, lack of estrogen has been linked to weight gain due to reduced energy needs and overeating, along with decreased energy expenditure as a result of reduced physical activity.1 So the causes of weight gain even among mice appear to be multifactorial.

Shifting Body Composition
However, weight gain isn't always reflected in increased pounds on the scale. Menopausal women tend to experience a shift in body composition in the form of abdominal fat even if they aren't prone to it before menopause. In a survey of 16,000 women, no difference was found in self-reported BMI between premenopausal and menopausal women; however, BMI didn't and still doesn't measure body composition.1 To add to the theory that this change in body composition is hormone related, hormone therapy in menopausal women has been shown to prevent accumulation of abdominal fat in aging women. Some researchers have found that women given estrogen therapy at menopause were leaner than those who didn't receive it; however, other studies have found no difference.5 Researchers propose the shift in body composition also may be a result of reduced muscle mass due to decreased physical activity, lifestyle changes, and genetics.5

Is Weight Gain OK?
While weight gain in menopause has been associated with increased chronic disease risk, some experts believe that a small to moderate weight gain may not be detrimental to health. In a 2001 study, researchers found that a moderate weight gain of 22 lbs (10 kg) over a 17-year period had a cardioprotective effect among menopausal women.6 Researchers hypothesized that the protection could be due to increased estrogen, originating from a rise in fat cells. It's important to note that, even with the weight gain, the women who experienced cardioprotection maintained a normal BMI (25 kg/m2). This protection wasn't seen among women who gained the same amount, but whose BMI was categorized as overweight or obese. Because the risks associated with overweight and obesity, such as breast cancer, cardiovascular disease, and type 2 diabetes, outweigh the current evidence supporting moderate weight gain in menopause, the Academy of Nutrition and Dietetics recommends that postmenopausal women achieve and maintain an optimal weight.7 "Considering the majority of women are overweight or obese, which is one risk factor for increased chronic disease, intuitively [accepting weight gain in menopause] doesn't make sense, and there isn't strong evidence to support [this idea]," Schwartz says. Yet, in a review of approximately 3 million women (not all postmenopausal), researchers found an increased risk of all-cause mortality in those with clinically defined obesity (BMI of ≥30), but not with overweight (BMI of 25 to <30).8 The authors suggested that it may be prudent to recognize that individuals can be metabolically healthy, yet overweight. For example, a review of BMI as a measure for metabolic health suggested that being slightly overweight may be helpful for some people, such as those with chronic disease, since extra weight may help in weathering complications due to their disease.9 The authors also indicated that waist circumference should be used in conjunction with BMI, since abdominal girth is known to be an indicator of chronic disease risk.9 In contrast, Blanck and colleagues' review, which examined weight gain among postmenopausal women over seven years, reported that weight gain of just 10 to 15 lbs is known to increase risk of heart disease and diabetes, and a 20- to 45-lb increase raises stroke risk.4

Taking Action
Whether hormonal changes or lifestyle factors cause weight gain, researchers agree that many women will require fewer calories postmenopause to maintain a healthy weight, which is only accomplished by either burning more calories through physical activity or eating fewer calories. A sensible approach is to do both. Research has shown that diet and exercise can help women avoid or reduce weight gain associated with menopause. In a study by Lee and colleagues of 34,000 women with a mean age of 54, those who exercised at moderate intensity for 60 minutes per day experienced about one-half as much weight gain as those who didn't exercise.10

Physical activity has many benefits in menopausal women, such as weight management, improved balance and flexibility, muscle mass maintenance, and better quality of life. In addition to moderate-intensity exercises including hiking, biking, and swimming, Rosenbloom recommends strength training. Age-related muscle atrophy usually begins at age 50 when a loss of both muscle mass and strength of about 10% to 15% per decade occurs. "Progressive, resistance strength training has been shown to increase muscle hypertrophy and strength, but even lifetime physical activity cannot completely buffer the age-related declines in muscle fiber loss," Rosenbloom says. Likewise, Schwartz encourages a moderate to high level of aerobic activity three times per week, plus some type of muscle-strengthening exercise. "This will serve to support a calorie-controlled diet and will help spare muscle tissue during weight loss and increase the thermodynamic activity of the body," Schwartz says.

While encouraging menopausal women to eat fewer calories and increase physical activity, it's important to recognize that they may be experiencing some of the early effects of aging such as reduced flexibility and balance, achy and stiff joints, and decreased muscle mass, all of which can contribute to fatigue and disinterest.
However, increasing physical activity by taking two to three 10-minute walks per day or two 15-minute walks per day can help counter fatigue and inspire clients to begin a daily exercise routine. Dietitians can recommend clients partake in aerobic exercise and strength training classes at their local YMCA or fitness facilities in their area and even consider yoga, which can address strength and flexibility issues simultaneously.

In addition to physical activity, developing healthful eating habits is essential since menopausal women have less room in their diets for calorie-rich snacks and desserts. Rosenbloom and Schwartz recommend women practice mindful eating, control portions, and focus on nutrient-dense foods such as fruits and vegetables.
Since losing weight can be daunting, especially if women have a significant amount to lose, Rosenbloom recommends setting a goal with clients to not gain weight. "If weight loss is hard, then just try to maintain where you are instead of gaining 1 to 2 lbs each year," she says. "By the time you're 70, that can be an extra 20 lbs."

Whatever goals are set, it's essential to assess clients' readiness for change, evaluate their nutrition and health literacy, and learn what motivates them. As a certified wellness coach, Schwartz suggests dietitians use MyPlate to teach clients what to eat and how much to eat, and encourage them to move a little more today than they did yesterday. If a client has retired, Schwartz suggests they focus on finding a new routine. "For many people," she says, "enrolling in a program that incorporates more intensive lifestyle behavior therapy is helpful."

The research supports that some changes in women's bodies during menopause are inevitable. However, women can prevent significant weight gain with consistent moderate-intensity exercise and a calorie-controlled, nutrient-dense diet. "The only sure way to lose or control body weight is to reduce or control calories," Schwartz says.

— Sherry Coleman Collins, MS, RDN, LD, is a private practitioner in Atlanta, specializing in food allergies and sensitivities, digestive disorders, and nutrition communications.

References
1. Davis SR, Castelo-Branco C, Chedraui P, et al. Understanding weight gain at menopause. Climacteric. 2012;15(5):419-429.

2. Bernstein M, Munoz N. Academy of Nutrition and Dietetics. Position of the Academy of Nutrition and Dietetics: food and nutrition for older adults: promoting health and wellness. J Acad Nutr Diet. 2012;112(8):1255-1277.

3. Brown WJ, Williams L, Ford JH, Ball K, Dobson AJ. Identifying the energy gap: magnitude and determinants of 5-year weight gain in midage women. Obes Res. 2005;13(8):1431-1441.

4. Blanck HM, McCullough ML, Patel AV, et al. Sedentary behavior, recreational physical activity, and 7-year weight gain among postmenopausal US women. Obesity. 2007;15(6):1578-1588.

5. Panotopoulos G, Raison J, Ruiz JC, Guy-Grand B, Basdevant A. Weight gain at the time of menopause. Hum Reprod. 1997;12(Suppl 1):126-133.

6. Singh P, Haddad E, Knutsen S, Fraser G. The effect of menopause on the relation between weight gain and mortality among women. Menopause. 2001;8(5):314-320.

7. Cox JT, Chapman-Novakofski K, Thompson CA. Practice Paper of the Academy of Nutrition and Dietetics Abstract: nutrition and women's health. J Acad Nutr Diet. 2013;113(11):1544.

8. Flegal KM, Kit BK, Orpana H, Graubard BI. Association of all-cause mortality with overweight and obesity using standard body mass index categories: a systematic review and meta-analysis. JAMA. 2013;309(1):71-82.

9. Heymsfield SB, Cefalu WT. Does body mass index adequately convey a patient's mortality risk? JAMA. 2013;309(1):87-88.

10. Lee IM, Djoussé L, Sesso HD, Wang L, Buring JE. Physical activity and weight gain prevention. JAMA. 2010;303(12):1173-1179.