Plant-based estrogen supplements aren’t as effective at maintaining bone health as claimed.

Plant-derived estrogen-like compounds found in dietary supplements are not as effective at reducing bone loss as claimed, a 2009 study showed. When compared to conventional therapies such as hormones or anti-osteoporosis drugs, the plant-based treatments were roughly four to five times less effective at reducing bone loss.

Over a period of 50 days, 11 postmenopausal women received six different treatments: soy cotyledon (the first leaves to appear on the plant), soy germ, kudzu (a plant used in traditional and folk medicine), red clover, risedronate (a drug used to treat osteoporosis), and estrogen combined with progesterone. Researchers measured the women’s bone loss after each treatment.

They found that the different treatments reduced bone loss to varying degrees: estrogen combined with progesterone, 24 percent; risedronate, 22 percent; soy cotyledon, 9 percent; soy germ, 5 percent. Red clover and kudzu had only marginal effects on reducing bone loss. Bone loss is a common feature of aging, especially among post-menopausal women.

Estrogen preserves bone health and is commonly prescribed as a treatment for women with osteoporosis. However, estrogen therapies and many common anti-osteoporosis drugs carry health risks. Plant-derived estrogen-like compounds, often referred to as phytoestrogens, are often touted as viable alternatives to conventional therapies.

This study demonstrates that plant-based therapies are less effective at reducing bone loss than hormonal or pharmaceutical therapies. They also underscore the importance of building bone mass in early life. Resistance exercise has been shown to preserve and even increase bone mass in postmenopausal women. Learn more about the effects of resistance training on bone health in this episode featuring Dr. Brad Schoenfeld.

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