CBD basics: what it is, how it is made, and how to read the label

What is CBD?

CBD does not produce the intoxication associated with THC. The World Health Organization's Expert Committee on Drug Dependence reviewed the compound at its fortieth meeting in June 2018 and wrote that "CBD is generally well tolerated with a good safety profile" (WHO 2018). The same report states that in humans CBD shows no effects indicative of abuse or dependence potential, and that no public health problems had been associated with the use of pure CBD at the time of review.

In the living plant, CBD exists mostly as cannabidiolic acid (CBDA). CBDA, THCA and the other acid forms are built from a single parent molecule, cannabigerolic acid (CBGA) (Walsh 2021). Heat, light and air convert the acid forms into the neutral cannabinoids people recognize on a label, a reaction called decarboxylation, and a 2018 study of 13 commercial hemp seed oils measured how fast CBDA converts at different temperatures (Citti 2018).

The legal status is split between two agencies. Hemp at or below the THC threshold is no longer a controlled substance, but FDA still regulates CBD products under the Federal Food, Drug, and Cosmetic Act, and FDA has approved 1 prescription drug that contains a purified form of CBD (FDA). The sections below cover each piece: extraction, spectrum, minor cannabinoids, drug tests, absorption, FDA status, labels and the 2026 definition change.

How is CBD extracted from hemp?

The review sorts methods into two families. Solvent-free methods rely on mechanical separation and may favor preservation of the plant's trichomes. Conventional solvent methods are simple and widely accessible but generally need longer processing times and more solvent, with the potential to co-extract impurities such as chlorophyll. Newer solvent techniques, including supercritical CO2, can shorten extraction time and improve selectivity (Lima 2026).

Temperature does double duty. Higher temperatures speed extraction but also promote decarboxylation of acidic cannabinoids and drive off terpenes, changing both the chemistry and the aroma of the finished extract (Lima 2026). A processor that wants a CBDA-rich extract runs cold; one that wants neutral CBD applies heat on purpose. The choice shows up on the certificate of analysis as the ratio of CBDA to CBD.

Solvent choice has a downstream test. Washington's cannabis quality rule, one of the more detailed state frameworks, fails a product when residual benzene exceeds 2.0 micrograms per gram and when ethanol, acetone, isopropanol or butanes exceed 5,000 micrograms per gram (WAC 314-55-102). A finished-product COA with a residual solvent panel tells you whether the extraction solvent was removed.

What is the difference between full-spectrum, broad-spectrum and isolate?

Trace THC is common in CBD products sold as hemp. When FDA tested 147 products purchased online for its 2020 report to Congress, 72 of them (49 percent) contained THC or THCA above the laboratory's limit of quantitation, with THC levels ranging up to 3.1 milligrams per serving (FDA 2020 report). A 2017 study of 84 CBD extracts bought online from 31 companies detected THC in 18 of them, 21.43 percent, at concentrations up to 6.43 milligrams per milliliter (Bonn-Miller 2017).

Broad-spectrum and isolate products are defined by what the lab cannot find. "ND" on a potency table means the analyte was below the method's limit of quantitation, not that it is absent. The lower the LOQ, the stronger the claim; the lab testing hub explains how to read that number and convert it to milligrams per container.

Full-spectrum products are the only category that can carry the plant's terpenes and minor cannabinoids in their original ratios, which is the basis of the entourage argument discussed below. They are also the category most exposed to the 0.4 milligram cap, to state restrictions on trace THC, and to drug-test concerns. The practical trade-off is spectrum breadth against THC exposure.

What are CBG, CBN, CBC and CBDA?

CBDA is simply the acid form of CBD as the plant makes it. Acid cannabinoids decompose with light, air and heat, and CBDA converts to CBD at a rate that depends on temperature, which is why a raw, cold-processed extract lists CBDA on its COA while a heated extract lists CBD (Citti 2018). The same acid-to-neutral logic applies to CBGA and CBG.

CBN formation has been measured directly. In dried cannabis resin held at 50 to 80 degrees Celsius, CBD and THC degraded while CBN formed, and in solution CBD was most stable between pH 4 and 6 (Jaidee 2022). Because natural CBN is a slow by-product of aging THC, manufacturers of CBN products may instead convert CBD chemically. The amended federal definition excludes cannabinoids that "were synthesized or manufactured outside the plant" (P.L. 119-37, section 781), so the production route matters and a supplier should be able to state it in writing. TODO: verify whether FDA has published the statutory cannabinoid lists as of October 2026.

Pharmacology is still being mapped. Minor cannabinoids have been shown in laboratory studies to act as agonists and antagonists at multiple targets, including CB1 and CB2 receptors, TRP channels, PPARs and serotonin 5-HT1a receptors, and the 2021 review that summarized this work describes current knowledge of minor cannabinoid pharmacology as incomplete (Walsh 2021). A product label that attaches a specific result to CBG or CBN is ahead of the published evidence.

Does CBD show up on a drug test?

The same study shows where the risk sits. When the participants inhaled vaporized CBD-dominant cannabis containing 100 milligrams CBD and 3.7 milligrams THC, 9 samples screened positive at the 20 ng/mL cutoff, 2 of those screened positive at 50 ng/mL, and 4 confirmed positive above 15 ng/mL (Spindle 2020). The authors concluded that "acute dosing of pure CBD will not result in a positive urine drug test" under federal guidelines, while products that also contain THC may.

Label accuracy is the second variable. In the 2017 online-purchase study, THC was detected in 21.43 percent of CBD extracts at up to 6.43 milligrams per milliliter, and only 30.95 percent of the 84 products were labeled within 10 percent of their measured CBD content (Bonn-Miller 2017). A full-spectrum product with trace THC, taken daily, is a different exposure from a single dose of isolate.

Timing matters because THC and CBD both persist. After repeated oral dosing in healthy adults, the terminal elimination half-life of CBD was approximately 60 hours, with effective half-life estimates of 10 to 17 hours (Taylor 2018). A systematic review of 24 human studies reported CBD half-life of 2 to 5 days after chronic oral administration (Millar 2018). Anyone subject to testing should choose isolate or broad-spectrum products with a COA showing THC below a low, stated LOQ, and should read the related answer on how long CBD stays in your system.

What is the entourage effect and how strong is the evidence?

The case for the effect rests on plausibility. Russo's review catalogued limonene, myrcene, alpha-pinene, linalool, beta-caryophyllene, caryophyllene oxide, nerolidol and phytol, noted that these flavor and fragrance compounds are common in human diets and carry Generally Recognized as Safe status, and proposed experiments to test cannabinoid-terpenoid interactions (Russo 2011). THC itself was isolated and synthesized in 1964, so the field is young.

The case against rests on the thin human record. Cogan's analysis of the primary literature concludes that claims of a cannabis entourage effect invoke ill-defined and unsubstantiated pharmacological activities, and that overstatement in both scientific and lay writing has been leveraged toward product marketing (Cogan 2020). No controlled human trial has isolated a terpene contribution in a hemp CBD product.

What this means for a buyer is simple. Full-spectrum and broad-spectrum products preserve more of the plant; isolate preserves none of it. Choosing between them on the basis of a proven synergy is not supported by the evidence as of 2026. Choosing on the basis of THC tolerance, drug testing and the 0.4 milligram per container cap is.

How does the body process CBD?

The systematic review by Millar and colleagues screened 792 articles and found 24 with human pharmacokinetic data. Half-life ranged from 1.4 to 10.9 hours after an oromucosal spray, 24 hours after intravenous dosing, 31 hours after smoking and 2 to 5 days after chronic oral use. Bioavailability after smoking was 31 percent, time to peak concentration ran from 0 to 4 hours, and peak concentration increased in fed states and in lipid formulations (Millar 2018).

The Phase I trial of a purified oral solution fills in the rest. The major circulating metabolite was 7-carboxy-CBD, followed by parent CBD and the active metabolite 7-hydroxy-CBD. Exposure rose less than proportionally with dose, CBD reached steady state after approximately 2 days of twice-daily dosing with 1.8-fold to 2.6-fold accumulation, and food changed the amount absorbed but not the time to peak or the terminal half-life (Taylor 2018).

Distribution explains the long tail. CBD is highly fat-soluble, with a reported volume of distribution of about 32 liters per kilogram, and it may accumulate in fat tissue; inhaled CBD reaches peak plasma concentration within 5 to 10 minutes, far faster than oral routes (WHO 2018). FDA notes that unapproved CBD products have not been evaluated for how they could interact with other drugs (FDA), which is a reason to talk with a pharmacist before combining CBD with anything prescribed.

Is CBD a dietary supplement under FDA rules?

The same page answers the food question the same way. Adding THC or CBD to food is a prohibited act under section 301(ll) of the Act, and the prohibition extends to animal food (FDA). FDA states that ingredients from parts of the plant that contain no THC or CBD, such as hulled hemp seed, may fall outside the exclusion. The page's content is current as of July 16, 2024.

Enforcement is claims-driven. FDA reports that it has sent warning letters to companies illegally selling CBD products that made unlawful health claims, and its warning-letter archive publishes laboratory results back to 2015, including a tincture labeled 200 milligrams CBD that measured 0.029 milligrams per gram (FDA warning letters). Structure/function wording on a label does not change the drug-exclusion analysis; it lowers claims exposure.

Congress has now layered a second set of definitions on top. Section 781 of Public Law 119-37 directs the Secretary of Health and Human Services to publish, within 90 days of enactment, lists of cannabinoids naturally produced by the plant and information on the term "container" (7 U.S.C. 1639o notes). TODO: verify whether those lists and the container guidance have been published as of October 2026.

What should a label tell you?

The rest of that sample is instructive. Of the 102 products that stated a specific CBD amount, 18 (18 percent) contained less than 80 percent of the labeled amount and 38 (37 percent) contained more than 120 percent; 138 of 147 tested products (94 percent) contained some CBD, and 2 products that listed CBD contained none (FDA 2020 report). The 2017 JAMA study found accuracy depended on format: 45.00 percent of oils were labeled accurately against 25.00 percent of tinctures and 12.50 percent of vaporization liquids (Bonn-Miller 2017).

Do the arithmetic on every label. A 30 milliliter tincture labeled 1,500 milligrams CBD with a 1 milliliter serving delivers 50 milligrams per serving; the same bottle with a 0.5 milliliter dropper mark delivers 25 milligrams. The number that matters is milligrams per serving, and a label that gives only "1,500 mg" without a serving size has left the work to you. The related answer on what 1,500 mg on a label means walks through it.

Total THC per container is the new line to look for. The amended federal definition excludes final products with "greater than 0.4 milligrams combined total per container" of total tetrahydrocannabinols including THCA (P.L. 119-37, section 781). A label or COA that reports THC only as a percentage, or only as "ND" without an LOQ, cannot show compliance with a milligram cap. The COA walk-through shows the conversion.

What changes in the federal hemp definition in 2026?

Read the two laws together. Section 781 takes effect 365 days after enactment, which is November 12, 2026, and it redefines hemp around "a total tetrahydrocannabinols concentration (including tetrahydrocannabinolic acid)" of not more than 0.3 percent (7 U.S.C. 1639o). Section 2019 of the Continuing Appropriations and Extensions Act, 2027, approved September 2, 2026, says the amendments "shall only apply with respect to products described in paragraphs (1)(C)(ii)(I) and (1)(C)(iv)(I)" until December 11, 2026 (P.L. 119-103). Those two paragraphs are the exclusions for cannabinoids "not capable of being naturally produced by a Cannabis sativa L. plant."

The practical calendar has 2 dates. On November 12, 2026, products containing cannabinoids the plant cannot naturally make leave the hemp definition. On December 11, 2026, the remaining amendments arrive: the total-THC standard, the exclusion of cannabinoids synthesized or manufactured outside the plant, the exclusion of intermediate products sold as final goods, and the 0.4 milligram per container cap (P.L. 119-37; P.L. 119-103).

The cap is small. The 2017 JAMA study measured THC up to 6.43 milligrams per milliliter in some CBD extracts (Bonn-Miller 2017), and FDA found THC up to 3.1 milligrams per serving in its 2020 sample (FDA 2020 report). Either figure exceeds 0.4 milligrams in a single serving, let alone a container. Isolate and broad-spectrum products with THC verified below a low LOQ are the formats positioned to remain inside the definition; the legality cluster tracks the rule as agencies interpret it.

How do you choose a first product?

Format sets the timeline. Oral formats such as tinctures swallowed with food, softgels and gummies peak at 4 to 5 hours and carry a 6 percent oral bioavailability estimate because of first-pass metabolism (WHO 2018). Tinctures held under the tongue follow the oromucosal data, with half-life of 1.4 to 10.9 hours and peak concentrations reached within 0 to 4 hours (Millar 2018). Topicals such as salves and roll-ons are applied to skin and are not designed to deliver CBD into the bloodstream.

Consistency beats intensity. Because a high-fat meal raised CBD exposure 4.85-fold and steady state took about 2 days of twice-daily dosing (Taylor 2018), take a product the same way each day, with or without food, and hold the serving steady for several days before changing it. The dosage cluster covers starting points by format.

Spectrum follows your constraints. If you are subject to drug testing, choose isolate or broad-spectrum with a COA showing THC below a stated LOQ in milligrams per container. If you want the plant's full profile and are not tested, full-spectrum is the option, with the caveat that it is the category most affected by the 0.4 milligram per container cap arriving December 11, 2026 (P.L. 119-103). Dogs and cats have their own page in the pets cluster; do not share human products with them.