Hemp (Cannabis sativa L.) is botanically closely related to hops.
Hemp may have been used in ancient times in beer brewing but very little evidence suggests that it was ever widely used for this purpose. In recent years hemp leaves have been used in Western countries as a substitute for aroma-hopping in a limited number of specialty beers. Other beers have used the seeds, usually lightly toasted before their addition to the kettle. Some have claimed that hemp seeds add a nutty flavor to beer, but many people have found the flavor unattractive. Because of legal restrictions, only materials from cultivars of hemp with a very low content of THC are allowed. The use of hemp in beers, therefore, only adds flavor and aroma and not narcotic effects. If legal, hemp can easily be grown for home use in brewing. That said, it seems fair to say that use of hemp products in commercial beers is more a matter of juvenile titillation than of flavor and aroma. After a brief splash in the 1990s, use of hemp in brewing has largely faded from the scene.