Hormone Changes That Affect Women During Menopause

The number on the scale may start creeping upward. Your waistline may change. Muscle definition may  decrease. Fat that was once carried primarily around the hips and thighs may increasingly accumulate  around the abdomen. 

It is tempting to blame all of this on “getting older.” Aging certainly plays a role, but research shows that the menopause transition brings its own changes in body composition. 

Menopause and aging are happening at the same time 

This is an important distinction. 

Women often enter perimenopause during the same years that age-related changes in muscle mass,  physical activity, sleep, and energy expenditure are occurring. 

Large studies suggest that overall weight gain during midlife is influenced substantially by aging, while  menopause has an additional effect on what that weight is made of and where fat is stored. (PubMed) The Study of Women’s Health Across the Nation, or SWAN, followed women through the menopause  transition and found something particularly interesting: as women entered the menopause transition, the  rate at which they gained fat approximately doubled and lean mass began to decline. These changes  continued until roughly two years after the final menstrual period. (PubMed) 

So two women can weigh the exact same amount on the scale while having very different metabolic health. One may have more muscle and less visceral fat. 

The other may have less muscle and more abdominal fat. 

That is why body composition can matter as much as body weight. 

Estrogen changes where fat tends to accumulate 

Estradiol levels fluctuate significantly during perimenopause and eventually decline after menopause. As estrogen decreases, women’s fat distribution tends to shift from a more traditionally “pear-shaped”  pattern around the hips and thighs toward a more central abdominal pattern. 

Longitudinal research has demonstrated increases in central and visceral adiposity across the menopause  transition. (PubMed) 

This matters because visceral fat is not simply stored energy. 

Visceral adipose tissue surrounds internal organs and is metabolically active. Higher levels are associated  with insulin resistance, abnormal lipids, inflammation, cardiovascular disease, and type 2 diabetes. So when a woman says: 

“My weight hasn’t changed very much, but my body looks completely different.”

There may be a physiologic explanation. 

Muscle is part of the equation 

Another important change involves lean mass. 

The SWAN study found that lean mass began decreasing during the menopause transition while fat mass  increased. (PubMed) 

Muscle is metabolically important tissue. It also plays a major role in glucose disposal, mobility, strength,  bone health, and maintaining metabolic function as we age. 

This is why simply trying to make the scale go down is not always the best goal. 

A woman who loses ten pounds but loses a significant amount of muscle along with it may be metabolically  worse off than someone who loses less total weight while preserving or gaining muscle. 

Sleep can make the problem harder 

Perimenopause can also bring: 

  • Hot flashes 
  • Night sweats 
  • Difficulty falling asleep 
  • Frequent waking 
  • Anxiety or mood changes 

Poor sleep isn’t merely inconvenient. 

Experimental research in women has shown that chronic sleep restriction can reduce insulin sensitivity  even without weight gain. A randomized study also found reduced insulin sensitivity after sleep restriction  in postmenopausal women. (PubMed) 

That creates another potential connection between menopause symptoms and metabolic health. This is why “just eat less” can be an incomplete answer 

Calories still matter. But telling a woman in menopause simply to “eat less and exercise more” ignores the  underlying changes affecting body composition. 

A more complete approach considers: 

  • Menopause stage 
  • Nutrition 
  • Protein intake 
  • Strength training 
  • Sleep 
  • Insulin resistance 
  • Thyroid function when clinically indicated 
  • Medications 
  • Stress 
  • Muscle mass 
  • Cardiometabolic risk factors 
  • Menopause symptoms 
  • Whether hormone therapy is medically appropriate 

What about hormone therapy? 

Menopausal hormone therapy should not be prescribed simply as a weight-loss drug. Its strongest evidence and established indications are for treatment of menopausal symptoms such as hot  flashes and night sweats, genitourinary symptoms, and prevention of bone loss in appropriately selected patients. Treatment needs to be individualized according to age, time since menopause, medical history,  symptoms, dose, route, and risk factors. (PubMed) 

Importantly, hormone therapy itself does not appear to cause the midlife weight gain women often fear.  The Menopause Society notes that weight changes in midlife are related to aging and hormonal changes  rather than hormone therapy causing weight gain. (The Menopause Society) 

The takeaway 

If your body is changing during your 40s or 50s, it may not simply be a matter of willpower. The menopause transition occurs alongside real changes in estrogen, body-fat distribution, lean mass, sleep, and metabolic function. 

The goal should not simply be to weigh less. 

The better goal is to protect muscle, metabolic health, strength, and healthy body composition as you move  through menopause.