Hemp - Cannabis sativa

Detailed Description

Today widely publicized and historically valued, hemp is a versatile herb recognized for its use in pain relief and as an antiemetic.

Botanical Information

The taxonomy of hemp is complex, having been classified in various plant families before securing its place in the Cannabaceae family, which also includes hops (Humulus lupulus). Hemp has three main varieties: Cannabis sativa, indica, and ruderalis. Each variety varies in size, shape, and the concentration of active compounds. These fundamental varieties have served as the basis for countless new cultivars developed to suit growers’ specific needs. Some sources claim there is only one species—Cannabis sativa—with two subspecies: Cannabis indica and Cannabis ruderalis.

Hemp is an annual or biennial herb that ranges from 0.3 to 6 meters in height. Its root is cylindrical and generally less developed than the above-ground part. The stem is upright, smooth or slightly hairy, quadrangular or hexagonal, and may be sparsely or densely branched. Leaves are long-petioled. At the base, they are opposite and palmate-compound; higher up, they become alternate, usually with three to eleven sharply toothed, elongated leaflets. The upper surface of hemp leaves is dark, gray-green and rough, while the underside ranges from finely hairy to nearly glabrous and is usually soft and pale green-gray.

Industrial hemp plants are dioecious—a plant is either male or female. Female plants are shorter and narrower, with lighter leaves that mature faster than male plants. The yellow, white, or greenish five-petaled flowers of hemp are prolific pollen producers and can self-pollinate without insect intervention. In both agricultural and legal contexts, female plants are far more significant. The more sunlight the plant receives, the more abundantly female flowers develop.

The fruit of hemp is a single-seeded, egg-shaped or spherical achene—slightly flattened and highly oil-rich, colored white, brown, or black. Seeds measure 2–5 mm long and 2–4 mm wide, with 1,000 seeds typically weighing around 10–30 grams. If seeds are dried at the optimal temperature of 60°C, they can be viable for many years.

Origin and Distribution

Cannabis sativa likely originated in Central Asia and spread rapidly worldwide thanks to its modest growing requirements. Evidence of use dates back to the Neolithic in both European and Asian civilizations. Hemp prefers warmer regions, so in Central and Southern Europe, it is cultivated mainly in the warmer areas, though it can also be found growing wild across various habitats—including in the Czech Republic. The best quality varieties in the Czech region are grown in Northern and Southern Moravia.

Usage / Dosage

Hemp use dates back over 10,000 years, with its fibers used in building materials. Ancient China reported eating hemp seeds and utilizing hemp medicinally. Emperor Shen-Nung, a champion of herbal medicine, described its use for constipation, gout, rheumatism, and mood elevation circa 2737 BCE. Hemp remains a fundamental herb in traditional Chinese medicine today. Historically, hemp is also valued for fiber and paper production.

Ancient Egypt’s “Ebers Papyrus” (1550 BCE) notes the use of hemp suppositories for painful hemorrhoids. Ancient Indian physicians recognized hemp's psychoactive effects and employed it to treat sleep disturbances, headaches, digestive complaints, and pain—including labor pain. In Ancient Greece, hemp leaves were applied topically to abrasions and wounds in horses, while dried seeds were eaten to dispel intestinal worms. In the Islamic world, from the 8th to the 18th century, Cannabis sativa was prescribed and consumed as a diuretic, antiemetic, analgesic, antipyretic, and anti-inflammatory agent.

Irish physician William Brooke O’Shaughnessy was the first to introduce the healing properties of hemp to Western medicine, prescribing it for muscle cramps, stomach spasms, and general pain. In 1964, A. Lockhart and M. West studied hemp’s therapeutic effects in Jamaica and contributed to developing Canasol, a hemp extract-based medication registered in the USA and marketed since 1987. The 1970s also saw the registration of medicinal products containing synthetic THC.

Though many early hemp medicines were withdrawn, between 1996 and 1999, voters in eight U.S. states approved medicinal cannabis. By 2014, 23 states had enacted cannabis laws, regardless of federal legislation. Similar reforms took place in Canadian provinces. Today, medical hemp is legal under strict regulations in the United Kingdom and the USA, and preparations containing THC are being legalized in several countries, including Austria, Belgium, Canada, Finland, Israel, the Czech Republic, the Netherlands, Spain, and the UK. In Europe and Asia, caffeine-free hemp tea is gaining popularity as a sleep aid.

In October 2003, research despite existing laws suggested hemp could have antioxidant and neuroprotective effects. Subsequent case reports highlight cannabinoids' potential in Huntington's, Alzheimer's, and Parkinson's disease, though more research is needed. In 2001, a publication indicated cannabis components may help with amyotrophic lateral sclerosis (ALS).

A 2005 review and meta-analysis pointed to possible hemp benefits in hard-to-treat disorders such as bipolar disorder due to promising pharmacology, raising hopes for future therapies for central nervous system diseases. In 2014, the American Academy of Neurology recommended testing hemp compounds for the treatment of brain diseases, with debate over their potential in multiple sclerosis.

Animal studies suggest hemp compounds may be analgesic and anti-inflammatory, and laboratory work indicates potential anti-cancer effects, particularly in breast and lung cancer cell lines, though human results remain unpredictable and further research is essential.

Emerging evidence suggests that cannabidiol (CBD) could slow cell destruction in type 1 diabetes, but this remains controversial among health authorities. Preliminary animal studies also point to the ability of hemp compounds to help reduce epileptic seizures. Epidiolex, a cannabinoid-based drug, is now in clinical trials in the USA for epilepsy treatment.

A 2007 review found promise for cannabis compounds in the treatment of Tourette’s syndrome. Earlier controlled studies with Marinol, a cannabinoid formulation, reported beneficial effects in early, mild cases of Tourette’s without significant adverse reactions.

Hemp proteins have been shown to support normal bone growth and development in children, encourage muscle mass and support bone health in general. Hemp seed protein contains up to 50% protein. According to nutrition guidelines, a product qualifies as high-protein if at least 20% of its energy is from protein; for “source of protein,” the threshold is 12%. By these standards, hemp protein is a valuable source.

One undeniable property of hemp is its antiemetic action—relieving nausea and vomiting. Some patients undergoing chemotherapy have found cannabis helps ease side effects. In cancer care, hemp compounds are also credited with pain relief, antispasmodic effects, and appetite stimulation. Despite its advantages, all health organizations agree that inhaled cannabis is unsuitable and carries health risks.

Active Compounds

Hemp contains a wide range of active substances—around 100 volatile sesquiterpenes and triterpenes, including tetrahydrocannabinol (THC), cannabidiol (CBD), alpha-pinene, myrcene, linalool, limonene, trans-beta-ocimene, terpinolene, trans-caryophyllene, alpha-humulene, and more.

The stems and leaves provide up to 25% fiber, making the plant ideal for ropes and building materials; the rest is woody matter. Seeds are rich in oil, with omega-3 and omega-6 fatty acids in a 3:1 ratio, similar to the profile of human skin. The seeds also contain palmitic, stearic, oleic, linoleic, and linolenic acids, along with fat-soluble vitamins A, E, and D.

Traditional Dosage

Dosage varies by form, concentration, and hemp variety. For herbal teas free of THC, drink as needed up to three times daily, regardless of meals.