The nettle plant grows mainly in North America and Europe, often up to five feet high. Nettle leaves are covered in tiny hairs that sting or poke like needles on contact. In fact, the plant's ability to irritate the skin was the basis for its use in traditional remedies. For example, stinging yourself with nettle leaves was considered a treatment for arthritis and applying a nettle leaf poultice to the skin was thought to draw out toxins from the body.
It seems that ancient folk healers were on to something, as contemporary studies have found that nettle can relieve inflamed joints, especially for those suffering from gout. The plant also has a diuretic effect, helping the body rid itself of excess fluids. This is beneficial for people with urinary tract infections and women with pre-menstrual bloating. Men with benign prostatic hyperplasia (enlarged prostate) may find that nettle helps slow prostate growth.
Perhaps it's best known benefit is as a hay fever remedy. Nettle contains quercetin, a flavanoid that can inhibit the release of histamine, so it can be effective for controlling nasal congestion and watery eyes associated with pollen and other allergies.
Nettle leaves are also edible, tasting similar to spinach. They are rich in iron, carotenoids and vitamin C.