Powerful natural antihistamine, quercetin reduces allergic reactions such as eczema, hay fever, and lowers the severity of asthma attacks.
Quercetin, a Mighty Antioxidant Powerhouse
Quercetin, sometimes called quercetol, is part of the flavonoid family, a group of polyphenols that scientists talk about a lot. Flavonoids—the largest family of polyphenols—are the renowned plant pigments that act as powerful antioxidants. They appear in many foods, especially fruits and vegetables, where they contribute to their vibrant colors.
In fact, the 4,000 varieties of flavonoids are divided into four groups:
- The flavanones found, among other things, in chocolate;
- The catechins present in green tea;
- The anthocyanins, pigments that color fruits and vegetables in shades ranging from blue to purple;
- The flavones, of which the famous quercetin is a member that interests us today.
It was Albert Szent-Györgyi, the Hungarian scientist, who discovered it. He was awarded the Nobel Prize in Medicine in 1937 for discovering vitamin C and flavonoids, and for exploring their biochemical properties.
Since then, quercetin has been recognized by the scientific community as the most active member of its family. It has also been the subject of dozens of scientific reports over the past 30 years.
Quercetin, a Weapon Against Aging and Allergies
Like all other flavonoids, quercetin acts in the body by strengthening the blood vessels. It is a powerful antioxidant, meaning it protects cells from the oxidation process linked to the action of free radicals responsible for premature aging.
But what really sets it apart is that quercetin is a natural and formidable antihistamine.
How Does Quercetin Fight Allergies?
itchy eyes, a runny nose, sneezing first thing in the morning: hay fever, known formally as pollen allergy or seasonal allergic rhinitis, affects roughly 20% of people.
Cause: pollen carried by the wind acts as powerful allergens. Spring allergy episodes are typically triggered by tree pollen, while in the summer it’s grass pollen that tickles the back of the throat.
Hay fever is an atopic disease. The immune system overreacts to external substances. It releases histamine, a signaling molecule of the immune system. The histamine released in the nasal or airway passages causes constriction and symptoms.
In vitro and animal studies have revealed quercetin’s effect on histamine and cytokine production, substances that play a fundamental role in allergy.
Indeed, quercetin acts by inhibiting histamine release. It would stabilize the membranes of the cells responsible, the mast cells. Thus, quercetin acts at the very source of allergic reactions, allowing a strong reduction of related symptoms by preventing histamine production: this is why it is referred to as an antihistamine.
Quercetin is therefore especially recommended for people suffering from allergies such as hay fever, but also in other forms: food allergies, asthma, eczema, or hives.
Where to Find Quercetin?
Quercetin occurs naturally in many foods. Capers and chervil are among the richest sources, delivering up to 18 mg per 100 g. Onions also contain a substantial amount, around 15 mg per 100 g.
The sources of quercetin are varied:
- Fruits: apples (especially with skin), red grapes, berries, cherries, citrus fruits, some seeds, and tree nuts like walnuts….
- Vegetables: garlic, broccoli, green beans, and herbs like fresh dill…
- Beverages: green tea, red wine;
- Plants: ginkgo, St. John’s wort.
Propolis also contains it.
It is recommended to incorporate these foods into daily meals, especially during hay fever season, and even consider anticipating by taking them before spring arrives.
To complement a healthy, balanced diet rich in quercetin, dietary supplements are also advised.
Quercetin can be found in capsules or tablets to take in the morning on an empty stomach or between meals, in a course of at least one month. Finally, it is recommended to pair quercetin with vitamin C since it improves absorption by the body and slows its elimination.
