Cultivated industrial hemp plants usually consist of a spindly main stalk covered with leaves. Considered a low-maintenance crop, hemp plants typically reach between 6 to 15 feet in height. Depending on the purpose, variety and climatic conditions, the period between planting and harvesting ranges from 70 to 140 days. One acre of hemp can yield an average of 700 pounds of grain, which in turn can be pressed into about 22 gallons of oil and 530 pounds of meal. The same acre will also produce an average of 5,300 pounds of straw, which can be transformed into approximately 1,300 pounds of fiber.

About half of the world market for hemp oil is currently used for food and food supplements (de Guzman 2001). For edible purposes, hempseed oil is extracted by cold pressing. Quality is improved by using only the first pressing, and minimizing the number of green seeds present. The oil varies in color from off-yellow to dark green. The taste is pleasantly nutty, sometimes with a touch of bitterness. Hemp oil is high in unsaturated fatty acids (of the order of 75%), which can easily oxidize, so it is unsuitable for frying or baking. The high degree of unsaturation is responsible for the extreme sensitivity to oxidative rancidity. The oil has a relatively short shelf life. It should be extracted under nitrogen (to prevent oxidation), protected from light by being kept in dark bottles, and from heat by refrigeration. Addition of anti-oxidants prolongs the longevity of the oil. Steam sterilization of the seeds, often required by law, allows air to penetrate and so stimulates rancidity. Accordingly, sterilized or roasted hemp seeds, and products made from hemp seed that have been subjected to cooking, should be fresh. The value of hemp oil from the point of view of the primary components is discussed below. In addition, it has been suggested that other components, including trace amounts of terpenes and cannabinoids, could have health benefits (Leizer et al. 2000). According to an ancient legend (Abel 1980), Buddha, the founder of Buddhism, survived a 6-year interval of asceticism by eating nothing but one hemp seed daily. This apocryphal story holds a germ of truth—hemp seed is astonishingly nutritional.
For many, the medical and therapeutic potential of cannabis is what makes legalizing the marijuana plant such an important political and social task. Federal prohibition has established barriers to comprehensive cannabis research in the United States. However, researchers in other countries continue to make significant contributions to our knowledge of the cannabis plant and how it affects the human body.
In modern times, the Rastafari movement has embraced Cannabis as a sacrament.[124] Elders of the Ethiopian Zion Coptic Church, a religious movement founded in the United States in 1975 with no ties to either Ethiopia or the Coptic Church, consider Cannabis to be the Eucharist, claiming it as an oral tradition from Ethiopia dating back to the time of Christ.[125] Like the Rastafari, some modern Gnostic Christian sects have asserted that Cannabis is the Tree of Life.[126][127] Other organized religions founded in the 20th century that treat Cannabis as a sacrament are the THC Ministry,[128] Cantheism,[129] the Cannabis Assembly[130] and the Church of Cognizance. Rastafarians tend to be among the biggest consumers of modern Cannabis use.
Hemp seeds contain virtually no THC, but THC contamination results from contact of the seeds with the resin secreted by the epidermal glands on the leaves and floral parts, and also by the failure to sift away all of the bracts (which have the highest concentration of THC of any parts of the plant) that cover the seeds. This results in small levels of THC appearing in hempseed oil and foods made with the seeds. Although most of the western hemp-growing world uses 0.3% THC as a maximum concentration for authorized cultivation of hemp plants, regulations in various countries allow only a much lower level of THC in human food products manufactured from the seeds. Currently, up to 10 ppm THC is permitted in seeds and oil products used for food purposes in Canada. In Germany, more stringent limits were set for food in 2000: 5 ppm in food oil, 0.005 ppm in beverages, and 0.15 ppm in all other foods. The US Drug Enforcement Administration published new regulations on hemp in the Federal Register on October 9th 2001 that in effect 4 months later would ban the food use of hemp in the US because any amount of THC would be unacceptable in foods (follow links at These proposals are currently being challenged by the hemp industry. Limits have been set because of concerns about possible toxicity and interference with drug tests (Grotenhermen et al. 1998). An extensive analysis of literature dealing with the toxicity of hemp is in Orr and Starodub (1999; see Geiwitz 2001 for an analysis). Because hemp food products are considered to have great economic potential, there is considerable pressure on the hemp industry in North America to reduce THC levels.
The scientific debate regarding taxonomy has had little effect on the terminology in widespread use among cultivators and users of drug-type Cannabis. Cannabis aficionados recognize three distinct types based on such factors as morphology, native range, aroma, and subjective psychoactive characteristics. Sativa is the most widespread variety, which is usually tall, laxly branched, and found in warm lowland regions. Indica designates shorter, bushier plants adapted to cooler climates and highland environments. Ruderalis is the informal name for the short plants that grow wild in Europe and Central Asia.