Does HRT cause weight gain?
Short answer: the evidence does not support it — the weight change women notice at midlife happens with or without hormones. The longer answer is more useful.
It is one of the most common reasons women hesitate to start hormone therapy — and one of the clearest places where the evidence and the worry point in different directions.
What actually causes midlife weight change
Through the menopause transition, body composition shifts toward abdominal fat and away from muscle — with or without hormone therapy, and often without any change in habits. Falling estrogen, changing insulin sensitivity, sleep fragmented by night sweats, and ordinary age-related muscle loss all push the same direction at once. The timing overlap with starting HRT is exactly that: an overlap.
What the evidence says about HRT specifically
Randomized data do not show that hormone therapy causes weight gain; if anything, treated women tend to show slightly less central-fat accumulation than untreated women. Some women notice transient bloating or breast fullness early in treatment — a formulation and dose issue, adjustable at follow-up — which is different from body-fat gain. Meanwhile, treating night sweats and sleep often makes the activity and appetite picture better, not worse.
What actually helps
Midlife weight change responds to medical evaluation, not blame: assessment of thyroid function, insulin resistance, medications, and sleep; resistance training and adequate protein to defend muscle; and, where appropriate, modern obesity medications — including GLP-1-class therapy, which our parent practice uses extensively. Menopause is the moment to treat metabolism seriously, not the explanation to stop trying.