Cannabis contains more than 550 identified chemical compounds, including over 100 cannabinoids, dozens of terpenes, flavonoids, fatty acids, and various vitamins and minerals. The two most well-known compounds are THC, which produces the “high,” and CBD, which does not. But the plant’s chemistry goes far deeper than those two molecules.
Cannabinoids: The Signature Compounds
Cannabinoids are the compounds that make cannabis unique. They work by binding to receptors in your brain and throughout your body that are part of what’s called the endocannabinoid system, a network your body uses to regulate mood, pain, appetite, and sleep. Your body actually produces its own versions of these chemicals naturally. The cannabinoids in cannabis essentially plug into the same system.
THC is the primary psychoactive cannabinoid. It binds strongly to receptors concentrated in the brain, which is why it alters perception, mood, and cognition. CBD, the second most abundant cannabinoid, interacts with the same receptors but doesn’t produce intoxication. CBD has shown therapeutic potential for conditions like epilepsy and is the active ingredient in an FDA-approved seizure medication.
Beyond THC and CBD, cannabis contains a long list of minor cannabinoids that appear in much smaller quantities. These include CBG (sometimes called the “parent” cannabinoid because it’s a chemical precursor to both THC and CBD), CBN (which forms as THC ages and degrades), and THCV (a compound structurally similar to THC but with different, sometimes opposite effects). THCV, for instance, may act as an antagonist at the same brain receptors THC activates, potentially dampening some psychoactive effects rather than enhancing them. Breeders are actively developing strains with higher concentrations of these minor cannabinoids, though most cannabis flowers contain only trace amounts. Early research suggests minor cannabinoids may have potential benefits for neuropathic pain, neurodegenerative diseases, epilepsy, and skin disorders, though much of this work is still preliminary.
Terpenes: What You Smell and Maybe Feel
Terpenes are aromatic compounds responsible for the distinctive smell of cannabis. They’re not unique to cannabis. Myrcene is found in mangoes, limonene in citrus peels, pinene in pine needles. But cannabis produces them in particularly complex combinations, with researchers identifying over 100 different terpenes across various strains.
The two most common terpenes in cannabis are beta-caryophyllene and myrcene. Myrcene is the smallest terpene but the most prevalent across most cannabis varieties. It has sedative and anti-inflammatory properties in lab studies. Beta-caryophyllene, which has a spicy, peppery aroma, stands out because it’s the only terpene known to directly interact with the endocannabinoid system by binding to CB2 receptors (the ones concentrated in immune tissues rather than the brain). Other common terpenes include alpha-pinene (the pine-scented compound), limonene (citrusy, with potential mood-lifting properties), and linalool (also found in lavender, associated with calming effects).
There’s growing interest in whether terpenes work together with cannabinoids to shape the overall effects of different cannabis strains, a concept sometimes called the “entourage effect.” This is why two strains with similar THC levels can feel noticeably different.
Flavonoids and Cannflavins
Cannabis also contains flavonoids, the same class of plant pigments found in berries, tea, and dark chocolate. Some of these are common across the plant kingdom, but cannabis produces a unique subset called cannflavins (A, B, and C) found nowhere else in nature. These compounds have shown anti-inflammatory and neuroprotective properties in laboratory studies, though research on them is still in early stages. Cannflavin A in particular has attracted interest for its potential to protect nerve cells from damage.
Where These Compounds Are Made
Nearly all of the cannabinoids, terpenes, and flavonoids in cannabis are produced and stored in tiny, mushroom-shaped structures called trichomes that cover the plant’s flowers and, to a lesser extent, its leaves. If you’ve ever noticed the frosty, crystalline coating on cannabis buds, those are trichomes. There are three types: bulbous (tiny and low to the surface), sessile (a small globe on a very short stalk), and stalked (a larger globe on a tall stalk). The stalked trichomes on mature flowers produce the greatest amount of cannabinoids. Inside each trichome, specialized cells at the base of the globe synthesize these compounds and deposit them into a storage cavity just beneath the outer membrane.
Nutritional Components in Seeds
The seeds of the cannabis plant (typically from hemp varieties) have a different chemical profile from the flowers. They contain essentially no THC or CBD but are nutritionally dense: roughly 25% protein and 35% fat. Hemp seed oil provides an unusually balanced ratio of omega-6 to omega-3 fatty acids at 3:1, which is considered optimal and isn’t matched by other common cooking oils like canola, sunflower, or soybean. The seeds also contain vitamin C, vitamin E, thiamine, riboflavin, and minerals including calcium, magnesium, potassium, phosphorus, iron, and zinc.
Contaminants That Can Show Up
Not everything in cannabis is supposed to be there. The plant is a hyperaccumulator of heavy metals, meaning it readily absorbs metals like lead, cadmium, mercury, and chromium from contaminated soil. These metals concentrate in the leaves, roots, and stems, and can also exit through the trichomes, the same structures that store THC and other cannabinoids consumers actually use. Several of these metals are carcinogenic.
Mold and bacteria are another concern. Cannabis flowers can harbor Aspergillus (a genus of mold that can cause lung infections), Salmonella, and E. coli. Regulated markets test for these pathogens and require that none be detected in finished products, but unregulated cannabis skips these checks entirely.
Cannabis concentrates and extracts introduce yet another category of potential contaminants: residual solvents. Common extraction methods use butane, propane, ethanol, or CO2 to strip cannabinoids from plant material. Testing labs screen for dozens of residual chemicals, including acetone, heptane, and various alcohols, to ensure they’ve been properly purged from the final product. This is one of the clearest safety differences between lab-tested products from legal markets and untested concentrates from illicit sources.