In late 2017, researchers with the University of Guelph in Canada published the first-ever study to document the ideal growing conditions for cannabis. Using liquid organic fertilizer with a PKN ratio of 1.3P–1.7K-4.0N, the experiment tested five increasing rates of fertilization. They also tested two coir-based soil-less growing media, or “substrates.”
I have digenerative disc disease/4 bulgin discs was taking 9---10mg hydrocodones a day... i started with 3 drops of 300mg and within 5 mins started feeling better than i have theses last 6 years or so... not only that, the inflamation has decrease substantially, i wake up with energy and have begun to work out again... if im making it seem like a miracle drug... its because it is... so the first week i took 3 drops twice a day... now 3 weeks in... im taking about 5 drops 3 times a day and zero pain pills... for the first time in years i have taken control of my life agin... not depending on doctor scripts/bills etc....

In the United States, the public's perception of hemp as marijuana has blocked hemp from becoming a useful crop and product,"[52] in spite of its vital importance prior to World War II.[53] Ideally, according to Britain's Department for Environment, Food and Rural Affairs, the herb should be desiccated and harvested towards the end of flowering. This early cropping reduces the seed yield but improves the fiber yield and quality.[54] In these strains of industrial hemp* the tetrahydrocannabinol (THC) content would have been very low.[52]

After seasonal harvests of specific cultivars, these high-CBD hemp crops are put through a specialized solvent-free extraction process to yield a hemp oil that is naturally high in cannabidiol. This pure hemp extract is then tested for safety, quality, and cannabinoid content before being exported to our processing facilities in the United States. Importing any cannabis or hemp product into the United States is a complicated and serious task, so we leave nothing to chance before our high-CBD hemp oil makes its journey across the Atlantic Ocean.

Other desirable features of hemp fibers are strength and durability (particularly resistance to decay), which made hemp useful in the past for rope, nets, sail-cloth, and oakum for caulking. During the age of sailing ships, Cannabis was considered to provide the very best of canvas, and indeed this word is derived from Cannabis. Several factors combined to decrease the popularity of hemp in the late 19th and early 20th centuries. Increasing limitation of cheap labor for traditional production in Europe and the New World led to the creation of some mechanical inventions, but too late to counter growing interest in competitive crops. Development of other natural fibers as well as synthetic fibers increased competition for hemp’s uses as a textile fiber and for cordage. Hemp rag had been much used for paper, but the 19th century introduction of the chemical woodpulping process considerably lowered demand for hemp. The demise of the sail diminished the market for canvas. Increasing use of the plant for drugs gave hemp a bad image. All this led to the discontinuation of hemp cultivation in the early and middle parts of the 20th century in much of the world where cheap labor was limited. In the 19th century softer fabrics took over the clothing market, and today, hemp constitutes only about 1% of the natural fiber market. At least some production of hemp for fiber still occurs in Russia, China, the Ukraine, Poland, Hungary, the countries of the former Yugoslavia, Romania, Korea, Chile, and Peru. There has been renewed interest in England, Australia, and South Africa in cultivating fiber hemp. Italy has an outstanding reputation for high-quality hemp, but productivity has waned for the last several decades. In France, a market for high-quality paper, ironically largely cigarette paper, has developed (such paper is completely free of the intoxicating resin). Modern plant breeding in Europe has produced several dozen hemp strains, although by comparison with other fiber crops there are relatively few described varieties of hemp. Since World War II, breeding has been concerned most particularly with the development of monoecious varieties. Gehl (1995) reviewed fiber hemp development in Canada in the early 20th century, and concluded that the prospects for a traditional fiber industry were poor. However, as outlined below, there are now many non-traditional usages for hemp fiber which require consideration. Hemp long fiber is one of the strongest and most durable of natural fibers, with high tensile strength, wet strength, and other characteristics that make it technically suited for various industrial products (Karus and Leson 1996).

In the EU and Canada, hemp has often been grown as a dual-purpose crop, i.e. for both fiber and oilseed. In France, dual purpose hemp is typically harvested twice—initially the upper seed-bearing part of the stems is cut and threshed with a combine, and subsequently the remaining stems are harvested. Growing hemp to the stage that mature seeds are present compromises the quality of the fiber, because of lignification. As well, the hurds become more difficult to separate. The lower quality fiber, however, is quite utilizable for pulp and non-woven usages.

Most pro-hemp initiatives in the United States are now focused on defining and distinguishing between industrial hemp and marijuana. Some pro-hemp supporters would like to move the control of U.S. hemp production from the DEA to the USDA. Proponents of legalizing hemp also argue that new technology to distinguish THC levels both in the field and from the air will allow for adequate production enforcement.

Cannabis is indigenous to Central Asia and Indian subcontinent,[183] and its use for fabric and rope dates back to the Neolithic age in China and Japan.[184][185] It is unclear when cannabis first became known for its psychoactive properties; some scholars suggest that the ancient Indian drug soma, mentioned in the Vedas, was cannabis, although this theory is disputed.[186]
If you would like to reproduce some or all of this content, see Reuse of NCI Information for guidance about copyright and permissions. In the case of permitted digital reproduction, please credit the National Cancer Institute as the source and link to the original NCI product using the original product's title; e.g., “Cannabis and Cannabinoids (PDQ®)–Health Professional Version was originally published by the National Cancer Institute.”
Yet, even with this progress, hemp businesses seem to face difficulty expanding in the US as they face challenges in traditional marketing and sales approaches. According to a case study done by Forbes, hemp businesses and startups have had difficulty marketing and selling non-psychoactive hemp products, as some online advertising platforms and financial institutions do not distinguish between hemp and marijuana.[100]
While cultivating marijuana’s non-intoxicating cousin is currently illegal in the U.S. outside of exceptions for state-approved hemp research programs authorized under the 2014 Farm Bill, there’s a strong possibility that industrial hemp will be broadly legalized—possibly by the end of the year—once the House and Senate reconcile their versions of a new Farm Bill and put it on the president’s desk.
Hemp is considered by a 1998 study in Environmental Economics to be environmentally friendly due to a decrease of land use and other environmental impacts, indicating a possible decrease of ecological footprint in a US context compared to typical benchmarks.[59] A 2010 study, however, that compared the production of paper specifically from hemp and eucalyptus concluded that "industrial hemp presents higher environmental impacts than eucalyptus paper"; however, the article also highlights that "there is scope for improving industrial hemp paper production".[60] Hemp is also claimed to require few pesticides and no herbicides, and it has been called a carbon negative raw material.[61][62] Results indicate that high yield of hemp may require high total nutrient levels (field plus fertilizer nutrients) similar to a high yielding wheat crop.[63]
Born in the foothills of the Rocky Mountains, we’ve been growing some of the safest and most thoroughly tested medical cannabis on the market since 2016. Our state-of-the-art facility in Cremona, Alberta, was specifically designed to keep our plants happy, and alongside a meticulous process of harvesting and curing we ensure only the best product arrives at your door.
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CBD has been producing a whole lot of buzz in the health community of late – but perhaps not the kind of buzz you might expect from a cannabinoid. Since you’re reading this, you’ve probably heard of CBD and its many touted benefits. From chronic pain to mental health, CBD has the potential to alleviate an astonishing number of ailments. But like many, you might be fuzzy on the details. Consider this your primer on all things CBD.
I have lower back pain with some arthritis and arthritis in my hands.ive recently tried CBD Oil. It really does work. I have the drops and ointment. They both work. Because of the back pain I never would have been able to go on a hike with my family. We had a lot of fun. And "No Pain", all day. I'm also Type 2 diabetic. Anxious to see what my A1C is next month. I'm a believer.
"We still don't fully understand all of the mechanisms involved in CBD's actions," says Marcel Bonn-Miller, Ph.D, who studies CBD and its effects, primarily on PTSD. "We know some pieces but definitely not the whole story at this point. A lot of our understanding of the many potential benefits of CBD is rooted in work either on the cellular level or in preclinical models with rodents."
I have sporadic back spasms for year I see a chiropractor monthly for maintenance (it help) and deal with daily Knee & hip joint pain due to my job (heavy mechanic/steel work with lots of walking). after reading all the great reviews on CBD oil I want to get off the daily ibuprofen regiment and try CBD oil. I would like to try it as a gel cap but would like some advise on dosage size. I also want to know how often I should take the CBD treatments. any and all advise is appreciated
Cooper recently got funding from the National Institutes of Health for a study looking at cannabinoids — including CBD in isolation — as a substitute for opioids, and numerous other clinical trials of CBD are underway. It will be several years before results are available, but these studies should help clarify both what benefits the substance may provide and any side effects it may come with. Most of the adverse effects so far associated with cannabis, such as impairments in short-term memory, coordination and judgment,2 come from products that contain THC as well as CBD, Cooper said, but we need to do more studies to find out for sure whether CBD has fewer risks. Studies are also needed to identify the best way to administer and dose CBD. “I get emails from people asking me what dose of CBD to use, and the truth is, we really don’t know,” Cooper said.
Fatty Acids. The quality of an oil or fat is most importantly determined by its fatty acid composition. Hemp is of high nutritional quality because it contains high amounts of unsaturated fatty acids, mostly oleic acid (C18:1, 10%–16%), linoleic acid (C18:2, 50%–60%), alpha-linolenic acid (C18:3, 20%–25%), and gamma-linolenic acid (C18:3, 2%–5%) (Fig. 37). Linoleic acid and alpha-linolenic acid are the only two fatty acids that must be ingested and are considered essential to human health (Callaway 1998). In contrast to shorter-chain and more saturated fatty acids, these essential fatty acids do not serve as energy sources, but as raw materials for cell structure and as precursors for biosynthesis for many of the body’s regulatory biochemicals. The essential fatty acids are available in other oils, particularly fish and flaxseed, but these tend to have unpleasant flavors compared to the mellow, slightly nutty flavor of hempseed oil. While the value of unsaturated fats is generally appreciated, it is much less well known that the North American diet is serious nutritionally unbalanced by an excess of linoleic over alpha-linonenic acid. In hempseed, linoleic and alpha-linolenic occur in a ratio of about 3:1, considered optimal in healthy human adipose tissue, and apparently unique among common plant oils (Deferne and Pate 1996). Gamma-linolenic acid or GLA is another significant component of hemp oil (1%–6%, depending on cultivar). GLA is a widely consumed supplement known to affect vital metabolic roles in humans, ranging from control of inflammation and vascular tone to initiation of contractions during childbirth. GLA has been found to alleviate psoriasis, atopic eczema, and mastalgia, and may also benefit cardiovascular, psychiatric, and immunological disorders. Ageing and pathology (diabetes, hypertension, etc.) may impair GLA metabolism, making supplementation desirable. As much as 15% of the human population may benefit from addition of GLA to their diet. At present, GLA is available in health food shops and pharmacies primarily as soft gelatin capsules of borage or evening primrose oil, but hemp is almost certainly a much more economic source. Although the content of GLA in the seeds is lower, hemp is far easier to cultivate and higher-yielding. It is important to note that hemp is the only current natural food source of GLA, i.e. not requiring the consumption of extracted dietary supplements. There are other fatty acids in small concentrations in hemp seed that have some dietary significance, including stearidonic acid (Callaway et al. 1996) and eicosenoic acid (Mölleken and Theimer 1997). Because of the extremely desirable fatty acid constitution of hemp oil, it is now being marketed as a dietary supplement in capsule form (Fig. 38).
In an in vivo model using severe combined immunodeficient mice, subcutaneous tumors were generated by inoculating the animals with cells from human non-small cell lung carcinoma cell lines.[23] Tumor growth was inhibited by 60% in THC-treated mice compared with vehicle-treated control mice. Tumor specimens revealed that THC had antiangiogenic and antiproliferative effects. However, research with immunocompetent murine tumor models has demonstrated immunosuppression and enhanced tumor growth in mice treated with THC.[24,25]
Industrial hemp is from the plant species Cannabis sativa and has been used worldwide to produce a variety of industrial and consumer products. Hemp is a source of fiber and oilseed grown in more than 30 nations. In the United States production is controlled under drug enforcement laws. To produce industrial hemp in the United States the grower must obtain a permit from the Drug Enforcement Agency (DEA).
Preliminary work in Germany (noted in Karus and Leson 1994) suggested that hemp could be grown on soils contaminated with heavy metals, while the fiber remained virtually free of the metals. Kozlowski et al. (1995) observed that hemp grew very well on copper-contaminated soil in Poland (although seeds absorbed high levels of copper). Baraniecki (1997) found similar results. Mölleken et al. (1997) studied effects of high concentration of salts of copper, chromium, and zinc on hemp, and demonstrated that some hemp cultivars have potential application to growth in contaminated soils. It would seem unwise to grow hemp as an oilseed on contaminated soils, but such a habitat might be suitable for a fiber or biomass crop. The possibility of using hemp for bioremediation deserves additional study.
Unlike other Cannabis sativa varieties and hybrids, which are mostly grown for their chemically potent flowers (or 'buds'), hemp is also legally distinguished from marijuana in the US as containing less than 0.3% of the cannabinoid chemical THC — considered to be the most intoxicating, psychoactive component in cannabis plants, as well as a treatment option for certain serious illnesses.
In the 1970s, President Nixon declared a “War on Drugs” and signed into law the Controlled Substances Act of 1970. This law established a set of banned drugs and created the Drug Enforcement Administration (DEA). It also unintentionally outlawed one of the world’s oldest domesticated crop, hemp. This not only led to the demise of hemp, but also an increased misconception of the plant.

As I research more I am disgusted with how we have all been deceived. I feel confident now with being able to research things on our own, at any moment in time, we can begin to take back our world. In the early 30’s one of the great media conspiracies unfolded. Publisher William Hearst, Dupont, the petroleum interests, the cotton lobby, the bankers and some ignorant politicians lead a crusade to ban hemp to line their pockets. Hemp can revolutionize our society. Please research and pass on!
Medical reviews published in 2017 and 2018 incorporating numerous clinical trials concluded that cannabidiol is an effective treatment for certain types of childhood epilepsy.[19][20] An orally administered cannabidiol solution (brand name Epidiolex) was approved by the US Food and Drug Administration in June 2018 as a treatment for two rare forms of childhood epilepsy, Lennox-Gastaut syndrome and Dravet syndrome.[13]

Low concentrations of CBD aren’t the only concern, either. Cannabis plants are hardy and tough, and their thick stalks possess a special property: bioremediation. When grown in contaminated soil, hemp plants absorb heavy metals and other chemical waste, effectively cleansing the terrain. While all plants absorb some chemicals from the soil, the structure, size, and genetic makeup of hemp make it especially adept at this task. Cannabis is so effective that crops of industrial hemp were planted in the aftermath of the 1986 Chernobyl disaster to help purify heavily irradiated soil. When hemp stalks are used for fiber, paper, and other nonconsumptive industrial purposes, the contaminants absorbed into the plants pose no threat to humans.
Cannabis is used in three main forms: marijuana, hashish and hash oil. Marijuana is made from dried flowers and leaves of the cannabis plant. It is the least potent of all the cannabis products and is usually smoked or made into edible products like cookies or brownies (see Factsheet: Marijuana Edibles). Hashish is made from the resin (a secreted gum) of the cannabis plant. It is dried and pressed into small blocks and smoked. It can also be added to food and eaten. Hash oil, the most potent cannabis product, is a thick oil obtained from hashish. It is also smoked.
Smoking cannabis can have an immediate effect. It can take an hour or more to feel the effects when eaten. Cannabis can make you feel relaxed, giggly, and hungry, or hallucinate or have a dry mouth. Using more cannabis can result in negative effects including blurred vision, bloodshot eyes, feeling sluggish, difficulty concentrating, slower reflexes, increased heart rate and lower blood pressure, and feelings of paranoia and anxiety.
I suffer fr migraines. Currently having Botox injections every three months for the last three years. This has helped went fr 24 to 30 migraines a month to 6 to 8 , now I'm back up to 14 to 20 a month. My doctor thought CBD oil might help. I have also started having anxiety attacks for a year now. I'm really confused with the dosages. Any thoughts would b helpful
Known for invigorating and uplifting sensations, with a high focus in the mind rather than the body, sativas are extremely popular as daytime-use strains and for social occasions. Sativas are also widely associated with the cerebral and creativity-enhancing effects of weed. Hence, they are lauded by artists and other inventive people who use cannabis.
Another Israeli group postulated that the anti-inflammatory and immunosuppressive effects of CBD might make it a valuable adjunct in the treatment of acute graft-versus-host disease (GVHD) in patients who have undergone allogeneic hematopoietic stem cell transplantation. The authors investigated CBD 300 mg/d in addition to standard GVHD prophylaxis in 48 adult patients who had undergone transplantation predominantly for acute leukemia or myelodysplastic syndrome (NCT01385124 and NCT01596075).[21] The combination of CBD with standard GVHD prophylaxis was found to be safe. Compared with 101 historical controls treated with standard prophylaxis, patients who received CBD appeared to have a lower incidence of grade II to grade IV GVHD, suggesting that a randomized controlled trial (RCT) is warranted.
Cannabis smoke contains thousands of organic and inorganic chemical compounds. This tar is chemically similar to that found in tobacco smoke,[88] and over fifty known carcinogens have been identified in cannabis smoke,[89] including; nitrosamines, reactive aldehydes, and polycylic hydrocarbons, including benz[a]pyrene.[90] Cannabis smoke is also inhaled more deeply than is tobacco smoke.[91] As of 2015, there is no consensus regarding whether cannabis smoking is associated with an increased risk of cancer.[92] Light and moderate use of cannabis is not believed to increase risk of lung or upper airway cancer. Evidence for causing these cancers is mixed concerning heavy, long-term use. In general there are far lower risks of pulmonary complications for regular cannabis smokers when compared with those of tobacco.[93] A 2015 review found an association between cannabis use and the development of testicular germ cell tumors (TGCTs), particularly non-seminoma TGCTs.[94] A 2015 analysis of six studies found little evidence that long-term or regular cannabis smoking was associated with lung cancer risk, though it could not rule out whether an association with heavy smoking exists.[95] Another 2015 meta-analysis found no association between lifetime cannabis use and risk of head or neck cancer.[96] Combustion products are not present when using a vaporizer, consuming THC in pill form, or consuming cannabis foods.[97]
Taking CBD oil is like drinking milk and calling it calcium, Hernandez said: There’s some in there, but at very low concentrations dispersed among a host of other ingredients. And what those other ingredients are is anyone’s guess. “The thing to know is that CBD hasn’t gone through the safety controls, the efficacy controls that we usually use, the clinical trials,” Hernandez said. “The jury is still out regarding how safe this drug is.”

Disclaimer: The entire contents of this website are based upon the opinions of Dr. Mercola, unless otherwise noted. Individual articles are based upon the opinions of the respective author, who retains copyright as marked. The information on this website is not intended to replace a one-on-one relationship with a qualified health care professional and is not intended as medical advice. It is intended as a sharing of knowledge and information from the research and experience of Dr. Mercola and his community. Dr. Mercola encourages you to make your own health care decisions based upon your research and in partnership with a qualified health care professional. If you are pregnant, nursing, taking medication, or have a medical condition, consult your health care professional before using products based on this content.
^ Jump up to: a b Deitch, Robert (2003). Hemp: American History Revisited: The Plant with a Divided History. Algora Publishing. pp. 4–26. ISBN 9780875862262. Retrieved 2013-11-16. Cannabis is ... a plant that played an important role in colonial America's prosperous economy and remained a valuable commercial commodity up until the Second World War.
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Three controlled trials demonstrated that oral THC has variable effects on appetite stimulation and weight loss in patients with advanced malignancies and human immunodeficiency virus (HIV) infection.[32] One study evaluated the efficacy of dronabinol alone or with megestrol acetate compared with that of megestrol acetate alone for managing cancer-associated anorexia.[40] In this randomized, double-blind study of 469 adults with advanced cancer and weight loss, patients received 2.5 mg of oral THC twice daily, 800 mg of oral megestrol daily, or both. Appetite increased by 75% in the megestrol group and weight increased by 11%, compared with a 49% increase in appetite and a 3% increase in weight in the oral THC group after 8 to 11 weeks of treatment. These two differences were statistically significant. Furthermore, the combined therapy did not offer additional benefits beyond those provided by megestrol acetate alone. The authors concluded that dronabinol did little to promote appetite or weight gain in advanced cancer patients compared with megestrol acetate. However, a smaller, placebo-controlled trial of dronabinol in cancer patients demonstrated improved and enhanced chemosensory perception in the cannabinoid group—food tasted better, appetite increased, and the proportion of calories consumed as protein was greater than in the placebo recipients.[41]
Hemp seeds have an attractive nutty taste, and are now incorporated into many food preparations (Fig. 34), often mimicking familiar foods. Those sold in North America include nutritional (granola-type) or snack bars, “nut butters” and other spreads, bread, pretzels, cookies, yogurts, pancakes, porridge, fruit crumble, frozen dessert (“ice cream”), pasta, burgers, pizza, salt substitute, salad dressings, mayonnaise, “cheese,” and beverages (“milk,” “lemonade,” “beer,” “wine,” “coffee nog”). Hemp seed is often found canned or vacuum-packed (Fig. 35). Alcoholic beverages made with hemp utilize hempseed as a flavorant. Hemp food products currently have a niche market, based particularly on natural food and specialty food outlets.
According to researchers, 25 percent of all cancer patients use medical marijuana. Cancer patients are finding relief from medical cannabis. And they want to know more about it. Research conducted at St. George’s University of London, found the two most common cannabinoids in marijuana, tetrahydrocannabinol (THC) and cannabidiol (CBD), weakened the ferocity of cancer cells and made them more susceptible to radiation treatment. Other studies have shown that medical marijuana treatments can slow the growth of cancer cells and halt their spread to other parts of the body.

The 2014 US Farm Bill allows states that have passed their own industrial hemp legislation to grow industrial hemp for purposes of research and development. Several states — including Kentucky, Colorado, and Oregon — are already conducting hemp pilot projects. Many other states are currently pursuing similar legislation and programs. After many years of prohibition, American farmers are finally reacquainting themselves with industrial hemp.

Tia has been Live Science's associate editor since 2017. Prior to that, Tia was a senior writer for the site, covering physics, archaeology and all things strange. Tia's work has appeared in Scientific American,, and the Milwaukee Journal Sentinel. Tia grew up in Texas and has an undergraduate degree in mechanical engineering from the University of Texas at Austin, a master's degree in bioengineering from the University of Washington and a graduate certificate in science writing from the University of California Santa Cruz. When she's not editing stories, Tia enjoys reading dystopian fiction and hiking.
Food and beverage products containing CBD were introduced in the United States in 2017.[54] Similar to energy drinks and protein bars which may contain vitamin or herbal additives, food and beverage items can be infused with CBD as an alternative means of ingesting the substance.[55] In the United States, numerous products are marketed as containing CBD, but in reality contain little or none.[56] Some companies marketing CBD-infused food products with claims that are similar to the effects of prescription drugs have received warning letters from the Food and Drug Administration for making unsubstantiated health claims.[57]
Settlements which date from c. 2200–1700 BCE in the Bactria and Margiana contained elaborate ritual structures with rooms containing everything needed for making drinks containing extracts from poppy (opium), hemp (cannabis), and ephedra (which contains ephedrine).[113] Although there is no evidence of ephedra being used by steppe tribes, they engaged in cultic use of hemp. Cultic use ranged from Romania to the Yenisei River and had begun by 3rd millennium BC Smoking hemp has been found at Pazyryk.[114]
In the 1970s, the taxonomic classification of Cannabis took on added significance in North America. Laws prohibiting Cannabis in the United States and Canada specifically named products of C. sativa as prohibited materials. Enterprising attorneys for the defense in a few drug busts argued that the seized Cannabis material may not have been C. sativa, and was therefore not prohibited by law. Attorneys on both sides recruited botanists to provide expert testimony. Among those testifying for the prosecution was Dr. Ernest Small, while Dr. Richard E. Schultes and others testified for the defense. The botanists engaged in heated debate (outside of court), and both camps impugned the other's integrity.[56][57] The defense attorneys were not often successful in winning their case, because the intent of the law was clear.[64]
In a follow-up, single-dose study involving 36 patients, it was reported that 10 mg doses of delta-9-THC produced analgesic effects during a 7-hour observation period that were comparable to 60 mg doses of codeine, and 20 mg doses of delta-9-THC induced effects equivalent to 120 mg doses of codeine.[51] Higher doses of THC were found to be more sedative than codeine.
CBD has also been demonstrated to exert a chemopreventive effect in a mouse model of colon cancer.[21] In this experimental system, azoxymethane increased premalignant and malignant lesions in the mouse colon. Animals treated with azoxymethane and CBD concurrently were protected from developing premalignant and malignant lesions. In in vitro experiments involving colorectal cancer cell lines, the investigators found that CBD protected DNA from oxidative damage, increased endocannabinoid levels, and reduced cell proliferation. In a subsequent study, the investigators found that the antiproliferative effect of CBD was counteracted by selective CB1 but not CB2 receptor antagonists, suggesting an involvement of CB1 receptors.[22]

Breeding for low THC cultivars in Europe has been reviewed by Bócsa (1998), Bócsa and Karus (1998), and Virovets (1996). Some researchers have claimed to have produced essentially THC-free strains, although at present no commercial cultivar seems to be 100% free of THC. THC content has proven to be more easily reduced in monoecious than in dioecious varieties. It should be possible to select THC-free strains, and there has been speculation that genetic engineering could be helpful in this regard. As a strategic economic and political tactic, France has been attempting for several years to have the European Union (EU) adopt legislation forbidding the cultivation of industrial hemp cultivars with more than 0.1% THC, which would mean that primarily French varieties would have to be cultivated in Europe. However, the Canadian government has found that some French material has proven to be excessively high in THC.

A randomized, placebo-controlled, crossover pilot study of nabiximols in 16 patients with chemotherapy-induced neuropathic pain showed no significant difference between the treatment and placebo groups. A responder analysis, however, demonstrated that five patients reported a reduction in their pain of at least 2 points on an 11-point scale, suggesting that a larger follow-up study may be warranted.[55]
Since Cannabis smoke contains many of the same components as tobacco smoke, there are valid concerns about the adverse pulmonary effects of inhaled Cannabis. A longitudinal study in a noncancer population evaluated repeated measurements of pulmonary function over 20 years in 5,115 men and women whose smoking histories were known.[5] While tobacco exposure was associated with decreased pulmonary function, the investigators concluded that occasional and low-cumulative Cannabis use was not associated with adverse effects on pulmonary function (forced expiratory volume in the first second of expiration [FEV1] and forced vital capacity [FVC]).

Molecular analytical techniques developed in the late 20th century are being applied to questions of taxonomic classification. This has resulted in many reclassifications based on evolutionary systematics. Several studies of Random Amplified Polymorphic DNA (RAPD) and other types of genetic markers have been conducted on drug and fiber strains of Cannabis, primarily for plant breeding and forensic purposes.[73][74][24][75][76] Dutch Cannabis researcher E.P.M. de Meijer and coworkers described some of their RAPD studies as showing an "extremely high" degree of genetic polymorphism between and within populations, suggesting a high degree of potential variation for selection, even in heavily selected hemp cultivars.[36] They also commented that these analyses confirm the continuity of the Cannabis gene pool throughout the studied accessions, and provide further confirmation that the genus consists of a single species, although theirs was not a systematic study per se.
In the EU and Canada, hemp has often been grown as a dual-purpose crop, i.e. for both fiber and oilseed. In France, dual purpose hemp is typically harvested twice—initially the upper seed-bearing part of the stems is cut and threshed with a combine, and subsequently the remaining stems are harvested. Growing hemp to the stage that mature seeds are present compromises the quality of the fiber, because of lignification. As well, the hurds become more difficult to separate. The lower quality fiber, however, is quite utilizable for pulp and non-woven usages.
The seeds are sown from mid-April to mid-May with grain drills to 4–6 cm sowing depth. Hemp needs less fertilizer than corn does. A total of 60–150 kg of nitrogen, 40–140 kg phosphorus (P2O5) and 75–200 kg of potassium [5] per acre for hemp fiber made before sowing and again later, maybe three to four weeks. When practiced, especially in France double use of fiber and seed fertilization with nitrogen doses up to 100 kg / ha rather low. Organic fertilizers such as manure can utilize industrial hemp well. Neither weeds nor crop protection measures are necessary.[52]