Chronic effects of isoflavones on cognition and aggression in a female population across the menstrual cycle

This research investigated the effects of a soy extract containing isoflavones on fluctuating mood, aggression and cognitive symptoms associated with hormonal changes across the menstrual cycle in healthy young women. Soy isoflavone supplementation was associated with improvements in some symptoms during menses but worsening of symptoms, particularly mood, during the luteal phase. In contrast, women using oral contraceptives reported fewer symptoms across all phases. These findings have implications for the treatment of women suffering from premenstrual symptoms and suggest that different doses or different treatments may be required across the cycle.