Hot flashes affect approximately 75% of postmenopausal women. Although hormone replacement therapy (HRT) is highly effective in reducing hot flashes, long-term HRT is associated with increased rates of breast cancer and heart disease. Safe, effective, and well-tolerated hot flash therapies are needed. The amino acids L-methionine and L-isoleucine have produced reductions in hot flash frequency. However, long-term L-methionine therapy may increase cardiovascular risks. This study will evaluate the short-term effects of L-isoleucine therapy. Data from this study will be used to conduct long-term studies in the future. Participants in this study will be randomly assigned to receive one of two different L-isoleucine doses for 2 weeks. Clinic visits will be made at baseline, Week 1, and Week 10. Participants will record the frequency and severity of their hot flashes in a diary.
Inclusion Criteria: * Postmenopausal * Experience over 5 hot flashes per day Exclusion Criteria: * Hormone Replacement Therapy (HRT) in the past 2 months