Red clover (Trifolium pratense) isoflavones are phytoestrogens, plant-derived compounds that can bind to estrogen receptors in the human body. Estrogen plays a crucial role in bone metabolism and the prevention of osteoporosis, particularly in postmenopausal women whose natural estrogen levels decline, increasing the risk of bone loss. Because of this, red clover has been investigated as a natural alternative to hormone replacement therapy for supporting bone health.

Several small clinical studies and randomized controlled trials have explored the effects of red clover isoflavones on bone mineral density (BMD) and bone turnover markers in peri- and postmenopausal women. Some studies have reported modest benefits, such as reduced bone loss or improved BMD at specific skeletal sites, particularly when red clover isoflavones are taken for at least 12 months. However, other studies have failed to show significant or consistent benefits compared to placebo. Systematic reviews and meta-analyses generally conclude that while there is some evidence of benefit, it is not strong or consistent enough to recommend red clover isoflavones as a primary treatment for osteoporosis.

In summary, there is a scientific rationale and some preliminary clinical evidence for using red clover isoflavones in supporting bone health, but the overall quality and consistency of the evidence is low to moderate. More robust, long-term studies are needed to clarify its efficacy. Therefore, red clover can only be considered a potential adjunct, not a proven therapy, for osteoporosis.