Metabolic Changes During Perimenopause & Menopause: Why Weight Gain, Belly Fat, and Muscle Loss Happen

As women transition through perimenopause and menopause, hormonal shifts—particularly declining estrogen—cause significant metabolic changes to your body that increases your risk of heart disease, stroke, diabetes and even Alzheimer’s dementia. Understanding these changes can help you take proactive steps to protect your health, manage weight, and maintain vitality well into midlife and beyond.

1. Increased Visceral Adipose Tissue (Belly Fat)

During perimenopause, fat distribution shifts from the hips and thighs toward the abdomen. This increase in visceral adipose tissue (VAT) isn’t just cosmetic—it’s metabolically active and linked to a higher risk of heart disease, type 2 diabetes, and metabolic syndrome. Lower estrogen levels play a role in this redistribution, as estrogen helps regulate where fat is stored in the body.

2. Increased LDL Cholesterol

Estrogen helps maintain healthy cholesterol levels by boosting HDL (“good”) cholesterol and keeping LDL (“bad”) cholesterol in check. As estrogen declines, LDL cholesterol levels often rise, leading to changes in lipid metabolism and a greater risk for atherosclerosis and cardiovascular disease.

3. Increased Blood Pressure

The hormonal changes of menopause can also contribute to higher blood pressure. Estrogen has a vasodilatory effect—it helps blood vessels relax. With less estrogen, blood vessels may become stiffer, increasing the likelihood of hypertension. Coupled with weight gain and changes in fat distribution, this further elevates cardiovascular risk.

4. Decreased Muscle Mass

Sarcopenia, or the gradual loss of skeletal muscle mass, accelerates during perimenopause and menopause. Muscle tissue is metabolically active and burns more calories than fat, meaning that losing muscle slows your resting metabolic rate and makes it easier to gain weight. Lower estrogen and progesterone levels, along with age-related factors, contribute to this decline.

5. Insulin Resistance

Hormonal changes also affect how your body handles glucose. With lower estrogen, women often experience reduced insulin sensitivity, meaning the body needs more insulin to manage blood sugar levels. Over time, this can lead to weight gain, increased belly fat, and a higher risk of developing type 2 diabetes.

How to Protect Your Metabolic Health

While these changes are a natural part of midlife, there’s a lot you can do to counteract their effects:

• Strength Training: Build and maintain lean muscle mass to support metabolism and insulin sensitivity. We recommend at least 2 strength training sessions weekly, lifting heavy with progressive overload to build muscle.

• Balanced Nutrition: Focus on fiber, protein (preferably plant proteins), healthy fats, and reduced refined carbohydrates. An easy way to do this is make sure each meal has lots of fruits and/or veggies, a protein, and a whole grain.

• Cardiovascular Exercise: Helps manage weight, improve cholesterol, and lower blood pressure. We recommend at least 150 minutes a week of moderate intensity exercise (think brisk walk), or at least 75 minutes of vigorous intensity exercise (think running).

• Stress Management & Sleep: Chronic stress and poor sleep can worsen insulin resistance and fat gain. Aim for 7-9 hours of sleep each night.

• Medical Support: Speak with a physician about menopause management options, including hormone therapy and targeted treatments for cholesterol, blood pressure, and glucose control.

The Bottom Line

Perimenopause and menopause bring real metabolic challenges—including increased belly fat, higher cholesterol and blood pressure, muscle loss, and insulin resistance. With a proactive approach that combines lifestyle strategies and medical guidance, you can protect your health, maintain energy, and support longevity during this transition.