Cannabis flavonoids are plant pigments and protective compounds from the same family you'll find in berries, onions and tea. Researchers have identified more than 20 in cannabis, including three cannflavins found almost nowhere else. In the plant, they help with color and with handling stress. What they do in people is still largely unstudied, so here's the science without the hype.
What Flavonoids Are
Flavonoids are polyphenols, a large family of natural compounds built on phenol rings. A 2016 overview counted about 6,000 of them. They turn up in fruits, vegetables, grains, bark, roots, stems, flowers, tea and wine, which is why nutrition researchers call many of them dietary flavonoids. They fall into subgroups, and three matter most for cannabis: flavones, flavonols and anthocyanins.
Flavonoids in Cannabis: How Many and Where
The tally so far tops 20, and most are flavones and flavonols, in both free and sugar-bound forms. They appear in seedlings, leaves and flowers, but researchers haven't detected them in roots or seeds.
Amounts shift with growing conditions. Cannflavin A levels depend on a plant's genetics plus temperature, sunlight, rainfall and humidity. In one study, genetically identical clones grown at higher elevations made more cannflavins.
What Flavonoids Do for the Plant
Plants make flavonoids for their own benefit. Across the plant world, these compounds:
- color flowers and fruits, which helps attract pollinators
- work as natural UV filters
- help defend against microbes and insects
- help plants cope with cold, drought and heat
The Main Cannabis Flavonoids
| Flavonoid | Group | What stands out in cannabis |
|---|---|---|
| Apigenin | Flavone | One of the main flavones found in the plant |
| Luteolin | Flavone | The starting material the plant uses to build cannflavins A and B |
| Kaempferol | Flavonol | Present in free and sugar-bound forms |
| Quercetin | Flavonol | Present in free and sugar-bound forms |
| Cannflavins A, B and C | Prenylated or geranylated flavones | Almost unique to cannabis; cannflavin C was isolated from a high-THC plant |
Cannflavins were first isolated in the 1980s from a cannabis extract with the cannabinoids removed. In 2019, scientists at the University of Guelph identified two enzymes the plant uses to turn luteolin into cannflavins A and B. That finding opens a route to making them in yeast or bacteria instead of extracting tiny amounts from plants. Cannflavin A isn't strictly exclusive to cannabis, either; it has also been found in a species of monkeyflower.
What Lab Research Is Exploring, and Its Limits
Most of the interest centers on inflammation. In early experiments, cannflavins reduced production of prostaglandin E2, an inflammation signaling molecule, in human cells grown in a dish. Later enzyme studies found that cannflavins A and B block two enzymes that make inflammation signals, one for PGE2 and one for leukotrienes. Other early work has looked at nerve cells in culture, parasites and computer models of viral proteins.
Those are cell, enzyme and computer studies, not trials in people. There's no human evidence that the flavonoids in cannabis flower or extracts change anything in the body, and the authors of a 2021 review call for clinical studies to find out. Research also lagged for decades because of cannabis's legal status. So think of flavonoids as interesting chemistry, not a reason to pick one product over another. If you have questions about a health condition, talk with your doctor.
Flavonoids vs. Terpenes
Terpenes and flavonoids often get mentioned together, but they do different jobs. Terpenes are the plant's main aroma compounds, and more than 200 volatile compounds have been reported in cannabis. Flavonoids are polyphenols that work inside plant tissue, coloring and protecting it.
| Flavonoids | Terpenes | |
|---|---|---|
| What you notice | Color, in some cases | Aroma and flavor |
| Reported in cannabis | More than 20 | 58 monoterpenes and 38 sesquiterpenes, among 200-plus volatiles |
| Required on Michigan labels | No | No |
Researchers would like to know whether either group shapes the so-called entourage effect, but that idea remains largely untested in people. For the aroma side of the story, see our guide to cannabis terpenes.
Why Some Strains Turn Purple
Purple, red and blue tones come from anthocyanins, a flavonoid subgroup. In cannabis, the main purple pigment is cyanidin-3-rutinoside, also called keracyanin. Anthocyanins build up in the outer layers of leaves and flowers, where they help protect the plant from UV light, cold and other stress.
Color starts with genetics, since a plant has to carry the trait. Temperature can then bring it out. In a 2025 study of a cannabis line bred to turn purple, anthocyanin levels peaked when plants were held at 8 °C and 15 °C (about 46 °F and 59 °F). They dropped at colder and warmer settings. CBD content in that study followed plant maturity, not color. Color is about pigment; it isn't a potency reading.
Why Flavonoids Rarely Appear on Labels
Michigan requires cannabis labels to show THC and CBD content, the testing lab, the harvest date where it applies, and required warnings. Flavonoids aren't on that list, so most packages never mention them. Terms like full-spectrum describe an extract that keeps more of the plant's compounds, not a measured flavonoid content. To compare products, start with the cannabinoid numbers; our guide to cannabinoids explains what they mean.
