If you’ve spent any time reading about herbs, nutrition, or plant medicine, you’ve probably come across the word flavonoid. It gets thrown around a lot – but what actually are they, and why do they keep coming up?
The basics
Flavonoids are a group of natural compounds found in fruits, vegetables, grains, bark, roots, stems, flowers, tea, and wine. (1) They’re part of what makes plants, well, plants – and they’ve been part of the human diet for as long as we’ve been eating them.
There are six subclasses of flavonoids: anthocyanidins, flavan-3-ols, flavanones, flavones, flavonols, and polymers. (4) You don’t need to remember all of those, but it’s worth knowing that different plants contain different types, and some contain several at once.
Some everyday sources you’ll recognise: berries, apples, citrus fruits, grapes, spinach, kale, broccoli, onions, tea, and cocoa (4) are all rich in flavonoids. So if you eat a fairly varied, plant-heavy diet, you’re already getting a decent amount of them without thinking about it.
What do they actually do?
This is where it gets interesting. Flavonoids are well known for their antioxidant, anti-inflammatory, anti-mutagenic, and anti-carcinogenic properties, as well as their ability to interact with key enzymes in the body. (1) In plain terms – they help protect your cells, calm inflammation, and seem to have a hand in a surprisingly wide range of processes.
The antioxidant piece is one of the most talked-about. Free radicals are unstable molecules that can damage your cells over time, and flavonoids help neutralise them. This is part of why a diet rich in colourful fruits and vegetables is so consistently linked to better health outcomes – the colour itself is often a sign of flavonoid content.
The anti-inflammatory side of things is just as significant. A lot of chronic health issues have inflammation at their root, and flavonoids seem to be pretty good at interrupting that process. This is why you’ll see them mentioned so often in herbal medicine – it explains a lot of why plants like mullein, chamomile, and elderflower do what they do.
Flavonoids and the brain
One area that’s getting a lot of attention right now is the link between flavonoids and brain health. Researchers believe flavonoids may help reduce cell-damaging free radicals, soothe inflammation, and may offer protective effects for brain cells. (4)
A large study using data from the Framingham Heart Study followed almost 3,000 people over 20 years and found that those with the highest daily flavonoid intake had a lower risk of developing Alzheimer’s or a related dementia than those who ate the smallest amounts. (4) The research is still developing and scientists are careful to point out that flavonoids are likely one piece of a bigger picture, but it’s a promising direction.
Flavonoids may also improve blood flow to the brain, which is particularly relevant given the known link between cardiovascular health and cognitive function. (4)
Where flavonoids show up in herbs
If you’re interested in herbalism, flavonoids are a name you’ll keep coming back to. They’re a big part of why so many medicinal plants have the effects they do. Quercetin, luteolin, apigenin, and kaempferol – all flavonoids – show up again and again in research into herbs like mullein, elderflower, chamomile, and St John’s Wort.
Flavonoids are now considered an important component in nutraceutical, pharmaceutical, medicinal, and cosmetic applications (1) – which is a fancy way of saying that what folk healers were doing with plants for centuries is now being taken seriously in labs and clinics.
Getting more of them
The good news is that eating more flavonoids doesn’t require a supplement routine or anything complicated. Most fruits and vegetables contain flavonoids, with some of the highest amounts found in berries, apples, citrus fruits, leafy greens, onions, tea, and cocoa. (4)
A few easy ways to up your intake: swap your morning coffee for green or black tea a couple of times a week, add berries to your breakfast, eat your onions (raw is better than cooked for flavonoid content), and reach for dark chocolate over milk chocolate. And of course – drink your herbal teas.
As always, this is for informational purposes only and isn’t medical advice – always check with a qualified practitioner for anything health-related.
Sources:
- National Library of Medicine – Flavonoids: an overview
- Healthline – What Are Flavonoids? Everything You Need to Know
- Oregon State University – Flavonoids
- Harvard Health Publishing – The thinking on flavonoids