Hormonal

During midlife, women experience a cumulative 6-year increase in fat mass of 3.4 kg and a decrease in skeletal muscle mass of 0.23 kg, driven by both chronological aging and ovarian aging (menopause).

If you are a woman in your 40s or 50s, expect your body composition to shift: you will likely gain about 3.4 kg of fat and lose 0.23 kg of muscle over 6 years, largely due to hormonal changes. This is not just 'getting older' but specifically linked to ovarian aging. To counteract this, prioritize resistance training to preserve muscle mass and manage caloric intake to limit fat gain, as these changes are driven by hormonal shifts (FSH) that affect how your body stores fat and muscle.