Menopause & Weight Gain

AFS Education

It is common for women to gain weight during mid-life, and it’s often blamed on hormonal changes related to perimenopause, menopause or treatment for those changes (i.e. hormone therapy). In the blog we will explore some of the research and science around potential body composition changes around menopause.

Changes as a result of declining levels of estrogen and progesterone

Changes in these hormones usually start between the ages of 45-55. Ovaries slow egg production and eventually stop. As a result, the ovaries produce less estrogen and progesterone. Menstrual cycles start to change, and menopause-related symptoms may appear (hot flashes, night sweats, etc.).

Is weight gain a side effect? What does the scientific research tell us?

There is quite a bit of research on this topic. Studies have looked at: women of the same age but in different stages of menopause; the rate of weight change in connection with menopausal status and hormonal changes; and ethnic variances. SWAN (Study of Women’s Health Across the Nation) conducted a large weight survey with 16,000 participants. In this survey no difference in BMI was found between premenopausal and post-menopausal women after age and other variables were adjusted for. SWAN did another study with a smaller group of women who were divided by ethnicity. The median weight of the women in the study did not differ by menopausal status. The average weight gain over the 3 year study was 4.5 pounds and was determined to be unrelated to menopausal status. Thus, the evidence seems to indicate that weight gain during menopause is not a direct result of hormonal changes.

If it’s not the hormones, why is it so much harder to lose weight or even maintain it?

Though these mid-life hormonal changes do not cause weight gain, there are factors that can contribute to weight gain.

• Changes in fat accumulation

Scientific evidence shows that estrogen depletion can cause a change in the distribution of body fat aka where we store our fat. Fat accumulation shifts to the abdominal area (even if a woman previously carried body fat mostly in her hips and thighs), which can change her overall shape and appearance. Much of that fat seems to be visceral fat, which is stored internally in the abdomen around the organs. Though hormonal fluctuations during perimenopause/menopause do change WHERE fat is accumulated, they do not cause fat mass to be gained. It still takes a 3500 calorie surplus to gain a pound of fat. That said, seeing fat appear where it didn’t used to be can certainly give the impression of weight gain.

• Changes in Energy Levels

Night sweats can cause sleep disruptions, leaving you feeling tired, irritable and less energetic. This can make it less likely that you will exercise, and overall decrease daily levels of physical activity. Additionally, when you do exercise, decreased energy can affect the intensity level at which you workout. All of these factors may result in less calories being expended over the course of a day, week, or year, and thus fat accumulation

• Changes in Activity Levels

Women generally become less physically active during their 40s and beyond. This change is due to lifestyle changes, such as the demands of work, kids, etc., replacing or taking priority over physical activity. At any age, burning fewer calories from being less active and not changing caloric intake increases weight and fat mass.

• Changes as a Result of Aging

·        Decreased lean mass (as you lose muscle your metabolic rate will slow). This happens as we age typically at a rate of 1-2% per decade, but it is largely due to decreased activity levels.

·        Decreased aerobic capacity. This declines 5-15% per decade starting at age 25. Decreased aerobic capacity means you have to increase the amount of time spent to expend the same number of calories as you did 10 years ago. The lower your activity levels, the greater the decrease.

·        Decreased caloric needs as a result of decreased activity levels.

What if I’m on hormone therapy?

Studies show that hormone replacement therapy is not associated with weight gain OR increased abdominal fat. In fact, it may prevent the abdominal fat accumulation associated with estrogen depletion. Studies have mostly shown a reduction in overall body fat, improved insulin sensitivity and lower rates of type 2 diabetes. That being said, AFS doesn’t have any recommendations one way or another on HRT and that is something to be discussed with a doctor.

So.. does menopause cause weight gain?

“There is no scientific evidence that menopause or hormone therapy is responsible for midlife weight gain.” North American Menopause Society

Studies have consistently shown that lifestyle and age, not menopause, do not CAUSE weight gain, although they may work to create an environment where it becomes easier to. Hormonal changes, however, do affect the patterns of fat distribution, causing greater accumulation in the abdominal area. Decreased energy needs along with decreased energy expenditure due to feeling ill, or shifting life priorities may also contribute to fat gain.

What is the best thing to do to prevent middle age weight gain? Monitor calorie intake (and make reductions if needed), exercise, and include resistance training to preserve lean mass. Also, keep hope! Menopause does not mean you are doomed to weight gain; you still have control even if things become harder.