Why men and women lose weight differently — and your diet might be fighting your hormones

Estrogen acts like a thermostat that makes young women's bodies resist calorie cuts, but turns down gradually after menopause — so the same diet works differently depending on your age and sex.

This means personalized weight loss guidance needs to account for sex and age, not just total calories, and researchers are now testing whether this explains why traditional dieting advice fails so many people.