Can hormone therapy cause weight gain as a side effect?

Hormone therapy can be linked to weight changes, but the picture is nuanced and depends on the type of therapy and the reason it’s used. In midlife women using menopausal hormone therapy (MHT, estrogen with or without progestogen), current evidence suggests it does not directly cause overall weight gain; rather, menopause itself and aging drive weight gain, while MHT may favor a healthier fat distribution away from the abdomen and may help indirectly via better sleep and symptom relief. ^[1] MHT is not recommended as a primary strategy to prevent or treat weight gain, even though it can modestly improve central fat distribution and quality of life. ^[2] In contrast, certain progestin treatments (for example, progestin therapy used for endometrial conditions) can increase appetite and cause bloating, so some people do experience weight gain during use. ^[3]

Key takeaways

• Menopausal hormone therapy by itself generally does not cause weight gain, and it may help shift fat away from the abdomen, which is metabolically favorable. ^{[1] [4]}
• MHT should not be used specifically to prevent or manage weight gain, despite possible benefits in body fat distribution and sleep. ^{[2] [5]}
• Progestin-based therapies (for certain gynecologic conditions) may lead to increased appetite, bloating, and possible weight gain in some users. ^[3]
• During cancer treatments that include hormone therapy, some people gain weight due to fatigue, lower activity, dietary changes, and treatment-induced menopause. ^[6]

Why weight changes happen on hormone therapy

• Aging and menopause: Midlife weight gain is more strongly linked to age-related metabolic changes than menopause alone; menopause tends to shift fat toward the abdomen (visceral fat). ^[7] MHT can counter some of that central fat shift but does not reliably reduce total body weight. ^[1]
• Medication effects: Progestins can stimulate appetite and fluid retention (bloating), which can increase scale weight. ^[3]
• Indirect factors: Hot flashes, poor sleep, and mood changes can worsen eating patterns and activity levels; controlling these symptoms with MHT may help users maintain healthier habits. ^[4]

Practical strategies to cope with weight gain

• Calorie balance with quality foods: A moderate daily calorie deficit (often 500–750 kcal) combined with more whole grains, fruits, and vegetables is a standard, sustainable approach to weight loss. ^[2]
• Structured plans: Meal replacements or structured meal planning can help some people adhere to calorie goals while maintaining adequate protein. ^[2]
• Strength and cardio: Combine resistance training to preserve or build lean mass with moderate-to-vigorous aerobic activity to increase energy expenditure and improve metabolic health. ^[2]
• Sleep and stress: Improving sleep and managing stress help regulate hunger hormones and reduce emotional eating; symptom control with appropriate hormone therapy may indirectly support these habits. ^[4]
• Team support: Social support and working with a clinician or dietitian improve adherence and outcomes. ^[8]
• Cancer-care context: If weight gain happens during hormone or chemotherapy, ask your team about fatigue management, tailored exercise, and nutrition referrals. ^[6] Practical steps include being mindful of high-sugar drinks and focusing on balanced meals. ^[9]

When to talk to your clinician

• Rapid or persistent weight gain, significant bloating, or swelling may need evaluation and potential adjustment of the hormone regimen. ^[3]
• If you’re on MHT primarily for hot flashes, discuss the expected benefits on symptoms and fat distribution, while setting realistic expectations about body weight. ^{[5] [1]}
• If you’re receiving progestin therapy and notice increased appetite or water retention, ask about dose, formulation, or alternative options that balance efficacy and side effects. ^[3]

Summary

• For most midlife users, menopausal hormone therapy does not directly cause overall weight gain and may improve central fat distribution; however, it is not a weight-loss treatment. ^{[1] [2]}
• Some hormone therapies especially certain progestins can increase appetite and bloating, contributing to weight gain for some people. ^[3]
• Evidence-based coping includes a modest calorie deficit, nutrient-dense eating, resistance and aerobic exercise, sleep optimization, stress management, and professional support. ^{[2] [8]}