Quercetin is the main active compound in fruits and vegetables that give them their pigment, though its superpowers extend far beyond vibrant colours.

Used as a natural antihistamine and anti inflammatory, this potent flavonoid has significant benefits to your overall health. Quercetin gives you immune system support, protects your heart and has anticancer properties, just to name a few. 

If you’re not getting enough Quercetin from your diet, supplements may be a proactive approach to improving your health and wellbeing. 

Here we explain how Quercetin works in your body, explain its anti-inflammatory, antihistamine and anti-ageing benefits and how to ensure you’re getting enough of it. 

What is Quercetin?

Quercetin is one of the most extensively studied flavonoids and is found naturally in fruits and vegetables including:

• Rocket
• Red apples
• Citrus fruits
• Coriander
• Red onion
• Broccoli
• Green tea
• Buckwheat
• Berries
• Cabbage
• Red Wine

The clue is in the pigment: fruits and vegetables with vibrant colours are usually higher in Quercetin (and leave the skin on! That’s where you’ll find the highest concentration). 

What Does Quercetin Do to Your Body?

The 7 Top Benefits of Quercetin:

1. Natural antihistamine:
   Quercetin inhibits the release of histamine in your body, lowering the hyperactivity of cells that cause an allergic reaction, helping to relieve symptoms of hayfever without the need for steroids or harsh medicines that cause drowsiness [2].
2. Anti inflammatory: 
   Quercetin suppressed the production of inflammatory cytokines, helping to repair intestinal ulcers, internal swelling and pain in those with inflammatory diseases [1].
3. Antioxidant:
   Quercetin is the most potent antioxidant flavonoid and scavenges free radicals within your body, fighting oxidative stress [1].
4. Protects Heart Health:
   High quercetin levels have been shown to improve circulation, lower LDL cholesterol, and strengthen the walls of blood vessels, thereby helping to prevent heart disease [2].
5. Immune System Support:
   By inhibiting cytokine production while maintaining the stability of mast cells, Quercetin has a proven ability to suppress inflammatory responses, promoting the health of the immune system [1].
6. Antibacterial and Antiviral:
   Flavonoids help to inhibit the growth of bacteria including E. Coli, Salmonella and Staphylococcus  [3].
7. May Lower Blood Pressure:
   A 2019 study showed that 150mg of supplemental Quercetin daily reduced the systolic blood pressure in overweight participants and reduced levels of LDL cholesterol [1]. 

Are You Getting Enough Quercetin?

If you’re eating handfuls of fruit and vegetables several times a day, it’s likely that you are getting enough Quercetin already.

However, the average Australian diet is lacking in sufficient intake.

Absorption of Quercetin depends on several factors including an individual's metabolism and which kinds of fibre or fats are consumed at the same time.

If you’re not consuming enough Quercetin through your diet, supplements may be beneficial, and potentially more bioavailable as they’re often combined with vitamins such as vitamin C & D.

Is Quercetin Anti-Ageing?

A number of factors increase the number of free radicals within your body, including smoke, alcohol, poor diet and natural ageing. Free radicals increase your risk of disease and speed up the ageing process. Antioxidants in Quercetin scavenge those free radicals, reducing oxidative stress, helping to prevent premature ageing [3].

Best Quercetin Products 2024

How Long Does it Take for Quercetin to Work?

Depending on your health concern, the length of time before effects of Quercetin supplementation may be noticed varies. For mild allergies, clinical studies have reported an average of 1-2 weeks before the reduction of symptoms including itching and watery eyes [1].

Is it Safe to Take Quercetin Daily?

Supplemental Quercetin is considered safe for healthy adults in doses up to 1000 mg daily for up to 12 weeks [2].

The effects of long term use are yet to be thoroughly researched. Consult your healthcare provider if symptoms continue. 

Who Should Not Take Quercetin? Side Effects, Precautions and Interactions. 

Supplemental Quercetin is not recommended for people:

• With kidney disease
• Whom are pregnant or breastfeeding
• With Caffeine sensitivities

Quercetin may decrease the effectiveness of antibiotics, and increase the side effects of Warfarin.

Consult your GP if you’re taking any medications or have any pre-existing conditions. 

Summary

Consuming Quercetin naturally or supplementally is considered beneficial for maintaining good health and preventing chronic diseases. 

As scientific research progresses, the therapeutic effects of Quercetin are becoming more clear. While a balanced diet is the best way to boost Quercetin levels, supplements may be beneficial where nutritional gaps exist, and combination with other vitamins including vitamins C & D may help increase bioavailability.

References:

[1] Aghababaei F, Hadidi M., 2023. Recent Advances in Potential Health Benefits of Quercetin. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10384403/

[2] WebMD, 2024. Quercetin: Uses, Side Effects and More. https://www.webmd.com/vitamins/ai/ingredientmono-294/quercetin 

[3] Medical News Today, 2024. What Are the Benefits of Quercetin? https://www.webmd.com/vitamins/ai/ingredientmono-294/quercetin