Where Does Nettle Have the Strongest Evidence?

The strongest clinical evidence for nettle concerns urinary symptoms associated with benign enlargement of the prostate, or benign prostatic hyperplasia (BPH).

Importantly, these studies mainly involve nettle root extracts. Clinical research has reported improvements in lower urinary tract symptoms, and this is one of the most established areas of medicinal use for nettle preparations.

Nettle leaf preparations have been investigated for other conditions. A controlled study explored their use in allergic rhinitis, with some positive findings, although the overall evidence in this area remains mixed. Nettle leaf extract has also been studied in people with type 2 diabetes, with some research reporting improvements in blood glucose control.

Other research directions include inflammatory conditions, skin applications and functional foods, but much of this evidence is still experimental or involves nettle as part of a combination rather than as a treatment on its own.

There is essentially no robust human clinical evidence for nettle essential oil, which is not a common medicinal preparation.