What is it?
Did your mom ever tell you to eat the insides of citrus peels? If so, she had probably heard good things about flavonoids and wanted her kids to have those benefits. Quercetin is one of the major flavonoid nutrients in the diet — like maybe even #1 — and plants produce it in response to light.
Where is it from?
When you eat an apple or orange — there it is. When you drink black or oolong or green tea — there it is. You also get quercetin from berries, onions, other citrus fruit, red wine, peppers, and garlic. Quercetin likes to concentrate in leaves and peels of plants, where it bolsters their protection.
What does it do?
- Quercetin is one of the relatively rare food nutrients that help cells “triage” themselves according to which are healthy vs. not functioning so efficiently — a process known as autophagy.
- The immune system puts quercetin to use for getting its strategy just right. Basic research (and in humans, too) finds that quercetin can help balance offense and defense players of the immune team.
- In a study of young men, supplementing quercetin improved exercise performance and boosted indicators that they were growing more energy-producing mitochondria in their muscles.
- With aging, the telomeres capping chromosomes get frayed, making genes and DNA prone to damage. Quercetin seems to help telomeres and DNA keep their integrity — kind of like shoelace protectors.
Guts love quercetin! Why? Because 1) it’s positive messaging for intestinal immune cell communities, and 2) it’s great food for the gut microbiome. Flavonoids like quercetin cultivate health-associated gut bugs like lactobacilli and bifidobacteria (you know them from yogurt, right?) as well as the gut celebrity Akkermansia.