Doctors in a depression study explained that red clover contains antioxidants known as isoflavones, or plant estrogens, and wanted to see how isoflavones would affect depression symptoms in women. In the study, 109 post-menopausal women diagnosed with depression and anxiety, average age 54, took 80 mg of red clover extract per day or a placebo. After 90 days, the women switched red clover and placebo and continued for another 90 days.
At the beginning and after each phase of the study, the women rated their emotional, social, and physical experiences during the previous week, including the ability to perform everyday tasks. In addition, the women described the effect their symptoms had on overall mood, sensitivity, bodily well being and physical activity.
Compared to the start of the study, after taking the placebo, women reported an average of 22 percent fewer symptoms of depression and anxiety, and after taking red clover, about 77 percent fewer symptoms.