Research appearing the journal Biofactors (2005; 25(1-4): 61-6) looked at the effect hormone replacement therapy (HRT) had on CoQ10 levels. Subjects included 50 premenopausal women, 33 postmenopausal women (healthy, and not on hormone replacement therapy, and 15 postmenopausal women on HRT. The serum levels of antioxidants, CoQ10, alpha tocopherol, gamma tocopherol, beta carotene and lycopene, were measured. In general, postmenopausal women had higher levels of CoQ10 than premenopausal women. However, postmenopausal women on HRT had lower levels of CoQ10 and gamma tocopherol. The women on HRT did have higher levels of alpha tocopherol.
