Chemical Cuisine Rating
Health Concerns: Cancer
Found in: Not approved by FDA for, but nonetheless added to, supplements, beverages, foods, pet foods, cosmetics, and personal care products
CBD is derived from cannabis, a class of plants that includes both marijuana and hemp. CBD is sold as an oil, in capsules, gummies, and powders, and added to various foods or beverages. It can also appear in cosmetics and personal care products such as creams and bath products. It is even found in some pet products.
Both marijuana and hemp also contain THC (tetrahydrocannabinol), which is psychoactive. Marijuana is high in THC and typically low in CBD, while hemp is low in THC and may be bred to be high in CBD. By itself, CBD does not provide the hallmark “high” associated with marijuana (i.e., it is not psychoactive). However, levels of THC high enough to have psychoactive effects have been found in tests of CBD-labeled products, albeit rarely.
CBD, THC, and other derivatives of marijuana have long been prohibited under federal law. However, the 2018 Farm Bill removed hemp—defined as cannabis and cannabis derivatives with no more than 0.3% THC on a dry weight basis—from the definition of marijuana under the Controlled Substances Act.
While this action decriminalized the possession and sale of hemp, the Food and Drug Administration has made clear in a Consumer Advisory and through enforcement actions that foods, and dietary supplements, as well as cosmetics and products for pets containing CBD, have not been approved, and it is currently illegal from a federal perspective to market CBD by adding it to a food or labeling it as a dietary supplement.
A major reason for the FDA’s position is that, under federal law and in most circumstances, FDA-approved drugs cannot be legally added to foods or dietary supplements. In 2018, FDA approved the high-dose CBD drug, Epidiolex, to treat seizures in two rare, severe forms of epilepsy. Epidiolex is the only approved drug containing CBD. At present, there is not sufficient evidence to support FDA approval of CBD for any other condition.
Some companies claim that CBD can prevent, treat, or cure serious diseases such as Alzheimer’s Disease, autism, AIDS, cancer, depression, and diabetes. Such claims are potentially dangerous since people may forgo other treatments that have been proven to be effective for these conditions. Others claim that CBD helps with anxiety, insomnia, energy, or pain, but again, the evidence has not been sufficient for FDA to approve CBD for those purposes. (FDA has approved three related drugs, made from synthetically derived cannabis compounds other than CBD, for certain uses, including the treatment of anorexia associated with weight loss in AIDS patients, and nausea and vomiting associated with cancer chemotherapy in certain patients.) FDA and CSPI both warn consumers to rely on evidence-based medical care, rather than on unproven claims related to CBD.
Several states have legalized marijuana and hemp for food, dietary supplements, recreational, and medical uses not approved by the FDA. These laws vary from state to state and are often in conflict with FDA regulations. Confusion over the legality of CBD-containing food and supplement products (or disregard for their legal status) has led to many such products entering the marketplace with little to no regulatory oversight or control over effectiveness, quality, potency, or safety.
The safety of CBD, especially at lower doses, is not well studied or understood, although research is ongoing. Adverse effects have been noted at doses of hundreds of milligrams (based on data collected in the Epidiolex clinical trials), whereas most food and supplement products are labeled to contain less than 20 milligrams. (A typical Epidiolex dose for an adult is 700 mg per day; exact doses depend on body weight). Referring to the high-dose Epidiolex studies, FDA has noted that there are “[m]any unanswered questions and data gaps about CBD toxicity… and some of the available data raise serious concerns about potential harm from CBD…including potential liver injury, interactions with other drugs, drowsiness, diarrhea, and changes in mood.”
Questions also remain about cumulative exposure to CBD across a broad range of consumer products and CBD’s impacts on vulnerable populations such as children, the elderly, and pregnant or breastfeeding women. CBD has not been studied in pregnant or nursing women, but since it is detected in breastmilk, nursing women should avoid it. Given the dearth of relevant data in pregnant animals, pregnant women should also avoid CBD. According to the agency (referring to studies in animals given CBD during pregnancy and lactation), “studies in animals have shown that CBD can interfere with the development and function of testes and sperm, decrease testosterone levels and impair sexual behavior in males.” FDA supports this stance, strongly advising against the use of CBD during pregnancy or while breastfeeding (talk to your doctor if you’re taking Epidiolex and become pregnant). FDA also notes that children are “a vulnerable population that may be at greater risk for adverse reactions due to differences in the ability to absorb, metabolize, distribute or excrete a substance such as CBD.”
CBD could also interfere with medications that are metabolized by a family of enzymes called the cytochrome p450 enzymes: CYP3A4 and CYP2C19. CBD may reduce the enzymes’ ability to metabolize those medications, raising their blood levels. However, the effect of CBD on these enzymes has only been demonstrated in animal and test-tube studies that use high doses of CBD. Forthcoming human studies will likely provide more insight into these and other potential safety concerns. You should speak with your doctor before taking CBD if you take medications such as some statins, calcium channel blockers, antidepressants, antiepileptics, proton-pump inhibitors, antibiotics, or antihistamines.
There are also mislabeling concerns with CBD products. In one study, only 30 percent of 84 CBD products purchased online were accurately labeled as to the amount they actually contained (some contained more, some less). The same study found THC above the federal government’s 0.3% acceptable threshold in 20 percent of CBD products purchased online. The amount of THC in a few of the studied products may have been sufficient to make a person (especially a child) feel intoxicated. Of note, the levels of THC found in some of these products may cause a positive test result on THC drug tests. As these data indicate, those who are seeking treatment for seizures should use the prescription product, Epidiolex, under the care of a licensed physician, as non-prescription versions lack adequate manufacturing controls.