Quercetin is a high potency bioflavonoid found in a variety of foods. It is also a structural element for flavonoids. It is found in many foods, such as onions (mainly red), apples, tea, nuts, various types of berries, cauliflower and cabbage.

Quercetin has strong antioxidant properties, like other bioflavonoids, and has the ability to stabilize cell membranes. These benefits contribute to the proper functioning of the body's defense mechanisms.

In addition, quercetin has significant anti-inflammatory activity, due to the immediate inhibition of several initial inflammatory processes. For example, it inhibits both the production and release of histamine and other allergic / inflammatory mediators. According to research studies it can have positive effects on allergies / inflammations and respiratory diseases such as bronchitis and asthma.

Quercetin also suppresses the production of the mutated protein p53 (a normal mutation in cancer) to almost undetectable levels. It also inhibits the transmission of signals for tumor growth, thus preventing cell division.