Hops
Hops, scientifically called Humulus lupulus, is an herb that is typically desired for its flowers which resemble cones (also called strobiles.) Its most popular use is in culinary preparations, especially beer. The first known use of hops for human consumption is about 1300 years ago, in Germany, as a beer stabilizer (preventing its spoil.)
Though the information available about hops is overwhelmingly about its use in beer as a stabilizer and for its aroma, more recently it has been recognized for its relaxing and soothing effects, especially in those suffering from anxiety or insomnia. Hops also has proven benefits in arthritis treatment, as well as prevention or even cure for cancer. However the study of hops in these areas in quite immature requiring much further research to determine efficacy.
Although hops is used in male enhancement preparations, the purpose for its use in these male enhancement formulas remains somewhat uncertain as hops is not known to have any sexually enhancing properties, although, it is likely that hops is included in these formulas for its relaxing and anti-anxiety properties.
Internal ingestion in humans is not known to have any side effects, but significant exposure to skin may cause skin lesions, although even in the exposure received by hops harvesters, less than 1 in 30 develop such lesions. There are also some reports of potential disruptions of menstrual cycle due to hops ingestion.