The active ingredients in saw palmetto berries are phytosterols from a variety of fatty acids. Phytosterols prevent conversion of
testosterone to DHT, which is thought to be responsible for causing the prostate to become inflamed.
These substances also prevent DHT from binding to prostate cells, further reducing the risk of prostate enlargement. Saw palmetto berries also have anti-estrogenic and anti-androgenic properties that keep inflammation in check. The herb has been widely studied as a remedy for BPH (benign prostatic hyperplasia) in both the United States and Europe with consistently favorable results.