Summary
- What is CBD? CBD (cannabidiol) is a compound derived from cannabis (a hemp plant also known as marijuana). Unlike other compounds found in cannabis, such as THC, cannabidiol is not believed to be a psychoactive compound affecting perception, and behavior.
- Does CBD work? CBD taken orally has been shown to reduce the frequency of certain types of seizures, and preliminary evidence suggests it may also help with anxiety, schizophrenia, insomnia, and other conditions. However, most of these effects have involved large doses of CBD — hundreds of milligrams per day, which is more than in many marketed CBD supplements and products. Oral CBD has not been shown to help for colds or the flu. CBD applied to the skin as creams, gels, and lotions may modestly reduce some forms of pain and might promote hair regrowth. (See What It Is and What It Does.)
- What did CL's tests of CBD products find? ConsumerLab found significant amounts of CBD in all of the products but the cost to obtain an equal amount of CBD from each product ranged more than 10-fold, from just 24 cents to $2.67 per 10 mg. Interestingly, there were many good, lower cost products available on the market than ConsumerLab found in its last Review in 2018. Levels of THC (tetrahydrocannabinol, a psychoactive compound) also tended to be much lower, with THC not detectable in most products. (See What CL Found and use the Results table to compare the amounts of CBD and other cannabinoids in products.)
- Best CBD Oil? Based on quality and value, ConsumerLab selected several Top Picks including an overall Top Pick as well as high, medium, and low-dose picks for oral use, a Top Pick among topical lotions and balms, and a Top Pick for Pets based on top quality and value.
- How to choose a CBD product: If you seek CBD, look for products that list the amount of CBD or cannabidiol per serving (and don't confuse that with the amount per entire bottle). If a product lists only "cannabinoids" it may contain some CBD but you won't know how much. Products may still have significant amounts of CBD if they list "hemp extract" as an ingredient, but don't expect much CBD if "hemp oil" is the only ingredient. Hemp extracts are more likely to contain a range of cannabinoids in addition to CBD (although it's not clear if this provides added benefit) and this is what is meant by the term "full-spectrum" on labels — but full-spectrum products may or may not contain THC. If you want to avoid THC, look for products that claim to be "THC-free." (See ConsumerTips.)
- How much CBD should I take and when? Most of the research with CBD has involved high doses (several hundred milligrams daily). However, many CBD products on the market are lower dose and it is not clear if this dosing is effective. Nevertheless, to greatly increase CBD absorption, take it with or shortly after a fatty meal. (See ConsumerTips: Dosage.)
- Is CBD legal? Although CBD is not psychoactive, it is not permitted to be sold as an ingredient in dietary supplements, as the FDA considers it an investigational new drug. Nevertheless, many CBD products are available on the market. It is legal to bring CBD products aboard domestic flights in the U.S. as long as it contains no more than 0.3% THC on a dry weight basis. FDA-approved CBD, such as the prescription medication Epidiolex, is also permitted. International flight rules will vary by country. (See Legality.)
- CBD safety, side effects and drug interactions: High-dose CBD can cause side effects such as decreased appetite, diarrhea, vomiting, fatigue, and fever. In people with Parkinson's disease, CBD may worsen motor symptoms. CBD may also cause abnormal results on liver-function tests and may interact with some medications including certain sedatives, blood-thinning drugs such as warfarin, and many others. For details, see Concerns and Cautions.
