An in vitro study of the effect of CBD on programmed cell death in breast cancer cell lines found that CBD induced programmed cell death, independent of the CB1, CB2, or vanilloid receptors. CBD inhibited the survival of both estrogen receptor–positive and estrogen receptor–negative breast cancer cell lines, inducing apoptosis in a concentration-dependent manner while having little effect on nontumorigenic mammary cells.[18] Other studies have also shown the antitumor effect of cannabinoids (i.e., CBD and THC) in preclinical models of breast cancer.[19,20]
One systematic review studied 30 randomized comparisons of delta-9-THC preparations with placebo or other antiemetics from which data on efficacy and harm were available.[31] Oral nabilone, oral dronabinol, and intramuscular levonantradol (a synthetic analog of dronabinol) were tested. Inhaled Cannabis trials were not included. Among all 1,366 patients included in the review, cannabinoids were found to be more effective than the conventional antiemetics prochlorperazine, metoclopramide, chlorpromazine, thiethylperazine, haloperidol, domperidone, and alizapride. Cannabinoids, however, were not more effective for patients receiving very low or very high emetogenic chemotherapy. Side effects included a feeling of being high, euphoria, sedation or drowsiness, dizziness, dysphoria or depression, hallucinations, paranoia, and hypotension.[31]

Despite its designation as having no medicinal use, Cannabis was distributed by the U.S. government to patients on a case-by-case basis under the Compassionate Use Investigational New Drug program established in 1978. Distribution of Cannabis through this program was closed to new patients in 1992.[1-4] Although federal law prohibits the use of Cannabis, Figure 1 below shows the states and territories that have legalized Cannabis use for medical purposes. Additional states have legalized only one ingredient in Cannabis, such as cannabidiol (CBD), and are not included in the map. Some medical marijuana laws are broader than others, and there is state-to-state variation in the types of medical conditions for which treatment is allowed.[7]
In Europe and Asia, hemp farming has been conducted for millennia. Although most countries ceased growing hemp after the second word war, some didn’t, including France, China, Russia, and Hungary, so that essential knowledge of how to grow and process hemp was maintained. When commercial hemp cultivation resumed in Canada in 1997, many farmers undertook to grow the crop without appreciating its suitability for their situation, or for the hazards of an undeveloped market. Hemp was often grown on farms with marginal incomes in the hopes that it was a savior from a downward financial spiral. The myth that hemp is a wonder crop that can be grown on any soil led some to cultivate on soils with a history of producing poor crops; of course, a poor crop was the result.
An in vitro study of the effect of CBD on programmed cell death in breast cancer cell lines found that CBD induced programmed cell death, independent of the CB1, CB2, or vanilloid receptors. CBD inhibited the survival of both estrogen receptor–positive and estrogen receptor–negative breast cancer cell lines, inducing apoptosis in a concentration-dependent manner while having little effect on nontumorigenic mammary cells.[18] Other studies have also shown the antitumor effect of cannabinoids (i.e., CBD and THC) in preclinical models of breast cancer.[19,20]
In the meantime, some physicians are forging ahead — and cashing in. Joe Cohen is a doctor at Holos Health, a medical marijuana clinic in Boulder. I asked him what CBD is good for, and he read me a long list of conditions: pain, inflammation, nausea, vomiting, intestinal cramping, anxiety, psychosis, muscle spasms, hyperactive immune systems, nervous system degeneration, elevated blood sugar and more. He also claimed that CBD has anti-cancer properties and can regenerate brain cells and reduce the brain’s levels of amyloid beta — a kind of protein that’s been linked to Alzheimer’s disease. I asked for references, noting that most of these weren’t listed in the Academies report or a similar review published in the Journal of the American Medical Association. “I think you just have to Google search it,” he said. It’s true that a preliminary study found hints that cannabinoids might reduce beta amyloid proteins in human brain cells, but the study was done in cells grown in a lab, not in people. As for cancer, the FDA sent warning letters last year to four companies that were selling products that claimed to “prevent, diagnose, treat or cure” cancer.

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, Wired.com, 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.
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.

As the demand for CBD products has increased, some states have started to take action. Over the past two years, 17 states have passed “CBD-only” laws, assuring parents who purchase CBD oil to treat their sick children that they won’t face arrest or prosecution from state law enforcement for possessing what the federal government still considers a Schedule I narcotic.

Jump up ^ Fernández-Ruiz J, Sagredo O, Pazos MR, García C, Pertwee R, Mechoulam R, Martínez-Orgado J (February 2013). "Cannabidiol for neurodegenerative disorders: important new clinical applications for this phytocannabinoid?". British Journal of Clinical Pharmacology. 75 (2): 323–33. doi:10.1111/j.1365-2125.2012.04341.x. PMC 3579248. PMID 22625422.
There is some speculation that George Washington smoked the flower of the cannabis plant in order to achieve a recreational high ("Like all farmers, Washington probably sampled the quality and potency of what he grew, and he may have used this hemp to treat his chronic tooth aches"),[53] but there is no evidence in any of his writings that he grew hemp for anything other than industrial purposes. It is sometimes supposed that an excerpt from Washington's diary, which reads "Began to seperate [sic] the Male from the Female hemp at Do.&—rather too late" is evidence that he was trying to grow female plants for the THC found in the flowers. However, the editorial remark accompanying the diary states that "This may arise from their [the male] being coarser, and the stalks larger"[115] In subsequent days, he describes soaking the hemp[116] (to make the fibers usable) and harvesting the seeds,[117] suggesting that he was growing hemp for industrial purposes, not recreational.
The leaves have a peculiar and diagnostic venation pattern that enables persons poorly familiar with the plant to distinguish a cannabis leaf from unrelated species that have confusingly similar leaves (see illustration). As is common in serrated leaves, each serration has a central vein extending to its tip. However, the serration vein originates from lower down the central vein of the leaflet, typically opposite to the position of, not the first notch down, but the next notch. This means that on its way from the midrib of the leaflet to the point of the serration, the vein serving the tip of the serration passes close by the intervening notch. Sometimes the vein will actually pass tangent to the notch, but often it will pass by at a small distance, and when that happens a spur vein (occasionally a pair of such spur veins) branches off and joins the leaf margin at the deepest point of the notch. This venation pattern varies slightly among varieties, but in general it enables one to tell Cannabis leaves from superficially similar leaves without difficulty and without special equipment. Tiny samples of Cannabis plants also can be identified with precision by microscopic examination of leaf cells and similar features, but that requires special expertise and equipment.[11]
In 2017, the cultivated area for hemp in the Prairie provinces include Saskatchewan with more than 56,000 acres (23,000 ha), Alberta with 45,000 acres (18,000 ha), and Manitoba with 30,000 acres (12,000 ha).[79] Canadian hemp is cultivated mostly for its food value as hulled hemp seeds, hemp oils and hemp protein powders, with only a small fraction devoted to production of hemp fiber used for construction and insulation.[79]
In addition to acting on the brain, CBD influences many body processes. That’s due to the endocannabinoid system (ECS), which was discovered in the 1990s, after scientists started investigating why pot produces a high. Although much less well-known than the cardiovascular, reproductive, and respiratory systems, the ECS is critical. “The ECS helps us eat, sleep, relax, forget what we don’t need to remember, and protect our bodies from harm,” Marcu says. There are more ECS receptors in the brain than there are for opioids or serotonin, plus others in the intestines, liver, pancreas, ovaries, bone cells, and elsewhere.
A 2016 review of animal studies indicated that cannabidiol has potential as an anxiolytic for relief of anxiety-related disorders and fear.[11] Reviews of preliminary research showed cannabidiol has potential for improving addictive disorders and drug dependence, although as of 2016, they indicated limited high-quality evidence for anti-addictive effects in people.[88][89][90]
In fact, numerous studies have looked at the relationship between CBD and pain, and the results are promising. Researchers have looked at various kinds of pain – from joint pain to cancer pain. One finding is that CBD increases levels of glutamate and serotonin – both neurotransmitters that play a role in pain regulation. And CBD’s anti-inflammatory properties help by tackling the root cause of much chronic pain.
Ten trials have evaluated the efficacy of inhaled Cannabis in chemotherapy-induced N/V.[35-38] In two of the studies, inhaled Cannabis was made available only after dronabinol failure. In the first trial, no antiemetic effect was achieved with marijuana in patients receiving cyclophosphamide or doxorubicin,[35] but in the second trial, a statistically significant superior antiemetic effect of inhaled Cannabis versus placebo was found among patients receiving high-dose methotrexate.[36] The third trial was a randomized, double-blind, placebo-controlled, crossover trial involving 20 adults in which both inhaled marijuana and oral THC were evaluated. One-quarter of the patients reported a favorable antiemetic response to the cannabinoid therapies. This latter study was reported in abstract form in 1984. A full report, detailing the methods and outcomes apparently has not been published, which limits a thorough interpretation of the significance of these findings.[37]
One of the reasons hemp fiber has been valued is because of its length. The primary bast fibers in the bark are 5–40 mm long, and are amalgamated in fiber bundles which can be 1–5 m long (secondary bast fibers are about 2 mm long). The woody core fibers are short—about 0.55 mm—and like hardwood fibers are cemented together with considerable lignin. The core fibers are generally considered too short for high grade paper applications (a length of 3 mm is considered ideal), and too much lignin is present. While the long bast fibers have been used to make paper almost for 2 millennia, the woody core fibers have rarely been so used. Nevertheless it has been suggested that the core fibers could be used for paper making, providing appropriate technology was developed (de Groot et al. 1998). In any event, the core fibers, have found a variety of uses, as detailed below. The long, lignin-poor bast fibers also have considerable potential to be used in many non-paper, non-textile applications, as noted below.
One study in mice and rats suggested that cannabinoids may have a protective effect against the development of certain types of tumors.[3] During this 2-year study, groups of mice and rats were given various doses of THC by gavage. A dose-related decrease in the incidence of hepatic adenoma tumors and hepatocellular carcinoma (HCC) was observed in the mice. Decreased incidences of benign tumors (polyps and adenomas) in other organs (mammary gland, uterus, pituitary, testis, and pancreas) were also noted in the rats. In another study, delta-9-THC, delta-8-THC, and cannabinol were found to inhibit the growth of Lewis lung adenocarcinoma cells in vitro and in vivo .[4] In addition, other tumors have been shown to be sensitive to cannabinoid-induced growth inhibition.[5-8]
The genus Cannabis was formerly placed in the nettle (Urticaceae) or mulberry (Moraceae) family, and later, along with the genus Humulus (hops), in a separate family, the hemp family (Cannabaceae sensu stricto).[44] Recent phylogenetic studies based on cpDNA restriction site analysis and gene sequencing strongly suggest that the Cannabaceae sensu stricto arose from within the former family Celtidaceae, and that the two families should be merged to form a single monophyletic family, the Cannabaceae sensu lato.[45][46]
As of March 2016, more than half of the 50 states have laws that allow for some hemp production, according to this chart. Yet, many states, such as California, where Jungmaven is based, will only allow for industrial hemp cultivation when federal law coincides with state law. That is, when Congress passes a bill permitting industrial hemp across the US. Currently, Jungmann imports his hemp from China, but he’s confident Congress will pass the bill legalizing industrial farming of hemp in July.
The most pressing need of the hemp industry in North America is for the breeding of more productive oilseed cultivars. At present, mainly European cultivars are available, of which very few are suitable for specialized oilseed production. More importantly, hempseed oil is not competitive, except in the novelty niche market, with the popular food oils. As argued above, to be competitive, hemp should produce approximately 2 t/ha; at present 1 t/ha is considered average to good production. Doubling the productive capacity of a conventional crop would normally be considered impossible, but it needs to be understood just how little hemp has been developed as an oilseed. There may not even be extant land races of the kind of hemp oilseed strains that were once grown in Russia, so that except for a very few very recent oilseed cultivars, there has been virtually no breeding of oilseed hemp. Contrarily, hemp has been selected for fiber to the point that some breeders consider its productivity in this respect has already been maximized. Fiber strains have been selected for low seed production, so that most hemp germplasm has certainly not been selected for oilseed characteristics. By contrast, drug varieties have been selected for very high yield of flowers, and accordingly produce very high yield of seeds. Drug varieties have been observed to produce more than a kilogram of seed per plant, so that a target yield of several tonnes per hectare is conceivable (Watson and Clarke 1997). Of course, the high THC in drug cultivars makes these a difficult source of germplasm. However, wild plants of C. sativa have naturally undergone selection for high seed productivity, and are a particularly important potential source of breeding germplasm.
An observational study assessed the effectiveness of nabilone in advanced cancer patients who were experiencing pain and other symptoms (anorexia, depression, and anxiety). The researchers reported that patients who used nabilone experienced improved management of pain, nausea, anxiety, and distress when compared with untreated patients. Nabilone was also associated with a decreased use of opioids, nonsteroidal anti-inflammatory drugs, tricyclic antidepressants, gabapentin, dexamethasone, metoclopramide, and ondansetron.[56]
^ Jump up to: a b Batalla A, Bhattacharyya S, Yücel M, Fusar-Poli P, Crippa JA, Nogué S, Torrens M, Pujol J, Farré M, Martin-Santos R (2013). "Structural and functional imaging studies in chronic cannabis users: a systematic review of adolescent and adult findings". PLOS One. 8 (2): e55821. doi:10.1371/journal.pone.0055821. PMC 3563634. PMID 23390554. The most consistently reported brain alteration was reduced hippocampal volume which was shown to persist even after several months of abstinence in one study and also to be related to the amount of cannabis use Other frequently reported morphological brain alterations related to chronic cannabis use were reported in the amygdala the cerebellum and the frontal cortex...These findings may be interpreted as reflecting neuroadaptation, perhaps indicating the recruitment of additional regions as a compensatory mechanism to maintain normal cognitive performance in response to chronic cannabis exposure, particularly within the prefrontal cortex area.

This guide is an introduction to anyone looking to inform themselves about the reality of cannabis. It covers basic information about the marijuana plant, cannabis preparations, and the crucial elements of plant anatomy and science. This guide to marijuana also gives an overview of the most popular medical and recreational uses of cannabis. It offers a survey of the most important medical cannabis research while highlighting emerging trends in the legal cannabis market. The guide also introduces those new to cannabis to the many ways to consume marijuana, and much more.
The CBD utilized in our tinctures is extracted from industrial hemp cultivated in the United States. To further ensure quality and purity, our industrial hemp goes through a supercritical CO2 extraction process to obtain the best possible CBD solution. This solution is then formulated by our board-certified pharmacists into finished products and sent out for third-party testing. Our CBD oil is made with high-quality CBD extracted from organic hemp that is abundant in naturally produced terpenes, oils, vitamins, omega fatty acids, and other components.
Those warning letters aside, there’s not a lot of federal oversight right now over the claims being made or the products that are being sold. Cohen warned against buying CBD products online, because “there’s a lot of scams out there.” Yet his clinic sells CBD, and he admits, “I say ‘Don’t buy online,’ but ours is worth doing, because we know what we’re doing. We ship all over.”
These CBD-only laws also attempt to impose some regulation on CBD oils, such as establishing how much CBD and THC such products must contain. For example, on June 1, the day I sat down with Hernandez in Fort Worth, Texas, Governor Greg Abbott signed the state’s Compassionate Use Act into law in Austin. The law requires that all CBD products contain no more than 0.5 percent THC and at least 10 percent CBD. However, the bill does not specify how the state plans to enforce this requirement. The law contains no language outlining how laboratories can test CBD products, what kinds of standards they would use, or who would regulate them.

Governor Jeff Colyer, M.D. signed Senate Bill 263 on April 20, which enacts the Alternative Crop Research Act allowing the Kansas Department of Agriculture to oversee the cultivation of industrial hemp in a research program. KDA has begun the process of developing rules and regulations to guide the Alternative Crop Research Act, which included an open dialogue and information exchange at a public forum May 11. Content from that forum is included on this page. 
A 2012 review found that the THC content in marijuana had increased worldwide from 1970 to 2009.[150] It is unclear, however, whether the increase in THC content has caused people to consume more THC or if users adjust based on the potency of the cannabis. It is likely that the higher THC content allows people to ingest less tar. At the same time, CBD levels in seized samples have lowered, in part because of the desire to produce higher THC levels and because more illegal growers cultivate indoors using artificial lights. This helps avoid detection but reduces the CBD production of the plant.[151]
Senate Majority Leader Mitch McConnell (R-KY) introduced new legislation in April that would declassify non-psychoactive cannabis varieties -- more commonly referred to as hemp -- from the Controlled Substances Act. The legislative proposal comes as part of McConnell's Hemp Farming Act of 2018, which would remove barriers placed on banking access and water rights in addition to legalizing the crop.
A limited number of studies have examined the effects of cannabis smoking on the respiratory system.[85] Chronic heavy marijuana smoking is associated with coughing, production of sputum, wheezing, and other symptoms of chronic bronchitis.[68] The available evidence does not support a causal relationship between cannabis use and chronic obstructive pulmonary disease.[86] Short-term use of cannabis is associated with bronchodilation.[87]
Even without changes at the federal level, there are steps that states could take on their own to make the CBD market safer. States with broad marijuana legality or CBD-only measures could mandate the calibration and regulation of testing labs, and use them to conduct safety testing. They could fund research into the benefits, dosing, and drug interactions of CBD through their public university systems. Medical boards could redouble efforts to educate physicians in what research exists regarding medical marijuana in all its incarnations, so that doctors are prepared to prescribe and manage these medications as they become available.
All of this makes CBD remarkably difficult for even the most dedicated health care providers to manage safely. Dr. Kelly Knupp, an associate professor of pediatrics and neurology at the University of Colorado, and the director of the Dravet Syndrome program at Children’s Hospital Colorado, said families of epileptic children have tried to bring CBD oils to the hospital for testing. “They’re just concerned that they don’t know exactly who’s growing [the hemp],” Knupp said. “They know it’s not being regulated.” But because CBD is a Schedule I controlled substance, high-tech, regulated laboratories, like those at the University of Colorado, can’t accept, store, or test CBD oils, lest they risk prosecution. “There is no such lab that can take that product,” Knupp said, which leaves any testing up to the unregulated testing centers that cater to the cannabis industry.
Cannabis sativa L. subsp. sativa var. sativa is the variety grown for industrial use, while C. sativa subsp. indica generally has poor fiber quality and female buds from this variety are primarily used for recreational and medicinal purposes. The major differences between the two types of plants are the appearance, and the amount of Δ9-tetrahydrocannabinol (THC) secreted in a resinous mixture by epidermal hairs called glandular trichomes, although they can also be distinguished genetically.[55][57] Oilseed and fiber varieties of Cannabis approved for industrial hemp production produce only minute amounts of this psychoactive drug, not enough for any physical or psychological effects. Typically, hemp contains below 0.3% THC, while cultivars of Cannabis grown for medicinal or recreational use can contain anywhere from 2% to over 20%.[58]
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