Quercetin Dosage

Quercetin Dosage

6 minute read

Quercetin is an antioxidant you can get from your diet or take as a supplement. Since quercetin is mostly found in fruits and vegetables, some people choose to take it as a supplement to their diet. People may want to take quercetin for many reasons, including allergy relief and disease prevention.


If you’re one of them, you may be wondering what’s a safe daily quercetin dosage. And you might also want to learn how much quercetin is in some of the foods you typically consume. This article will discuss a safe quercetin dosage, foods with quercetin, and health benefits and risks of taking the supplement.

Where is Quercetin Found?

Quercetin is a pigment found in many plants. These include common fruits and vegetables you may already eat, such as onions and blueberries. However, quercetin can also be found in some processed foods and beverages like wine and coffee.


Officially, quercetin is in the flavonoid family. You may already be familiar with the term flavonoids since these are touted as anti-inflammatories and immune system boosters. Antioxidants and anti-inflammatories help combat the effects of systemic inflammation in the body and free radicals from things like pollution.

What are the Benefits of Quercetin?

The main health benefits of quercetin are reduced inflammation in the body, lower blood pressure, and allergy symptom relief. Because of quercetin’s anti-inflammatory action in the body, it has shown some promise in fighting cancer and Alzheimer’s disease. 


Quercetin is most beneficial in preventing these conditions rather than reversing established disease processes. Other uses for quercetin include enhancing athletic performance and preventing some types of respiratory infections. Scientists and researchers have also studied quercetin’s ability to fight viruses, including herpes and encephalitis.     

What is a Safe Quercetin Dosage?

Since quercetin exists in fruits, vegetables, and beverages like green tea, most people consume between 5 and 400 milligrams each day. People who follow vegetarian or vegan diets may naturally get around 500 milligrams of quercetin daily from food. 


If you take extra as a supplement, you’ll obviously be consuming more on top of what you get from your food. However, other supplements contain small amounts of quercetin. Those supplements include St. John’s Wort, American elder, and Ginkgo biloba. 


More research needs to be done to determine a safe daily quercetin dosage, but preliminary findings show that up to 1,000 milligrams a day for 12 weeks is safe. Health professionals don’t know whether it’s safe to take more than 1,000 milligrams every day. They also don’t know if it’s safe to keep taking quercetin for more than 12 weeks. 


While the FDA regulates food safety, the agency does not oversee supplements. There is the potential that quercetin will interact with any other supplements you’re taking, including multivitamins. Plus, quercetin can interact with your prescription medications. For this reason, it’s best to ask your doctor before you take quercetin in supplement form. 

Side Effects of Taking Quercetin

The human body tends to not absorb quercetin well. But taking it with other vitamins like vitamin C can increase absorption rates. You could start to experience headaches or tingling in your extremities if excess quercetin builds up in your system. Extremities include your arms, hands, legs, and feet.


You also risk damaging your kidneys if you consume too much quercetin. Pregnant and breastfeeding women should not take quercetin as a supplement. While it’s safe to get some from your diet, taking additional amounts can put you and your baby at risk. 


Other drugs and supplements that impact liver function should not be mixed with quercetin supplements. These drugs and supplements include antibiotics and blood pressure medication. 

Which Foods Contain Quercetin?

Here is a list of foods with quercetin:


  • Broccoli

  • Olive oil

  • Tomatoes

  • Blueberries

  • Buckwheat

  • Onions

  • Grapes

  • Cherries

  • Red wine

  • Green and black tea

  • Oranges, lemons, limes

  • Kale

  • Asparagus

  • Peppers

  • Seeds and nuts


The number of milligrams each of these foods contains can vary. For example, a typical onion contains 300 milligrams. But most people don’t eat an entire onion in one meal or day. A common serving has about 52 milligrams, which is one of the highest concentrations you can find in fruits and vegetables.


In comparison, green tea has about 2.5 milligrams for every 100 milliliters you drink. That equals about 3.3 cups. Some tea enthusiasts might consume that much every day, but the majority of us don’t. Even if you did drink that much green tea, you wouldn’t be getting a significant amount of quercetin. 

Does My Body Need Quercetin?

In general, dieticians have not established a daily recommended intake for quercetin. They do know it’s not something your body can produce on its own. And given that it’s present in many natural, unprocessed foods, it seems there is a nutritious purpose behind it. 


However, there are other anti-inflammatories and immune boosters you can take. Supplements like vitamin C and zinc can serve the same purposes if you’re looking to fight the effects of free radicals and compromised immunity. 


With that said, quercetin does seem to have a stronger effect on treating chronic inflammation, decreasing all types of cancer risks, and preventing some neurological conditions. Quercetin also has a stronger effect on symptoms related to respiratory conditions, including asthma and severe and chronic allergies.


In addition, quercetin has antibacterial properties. For this reason, it has been effective in alleviating symptoms associated with digestive disorders and skin and urinary tract infections. If you’re thinking of starting supplements, discuss a safe quercetin dosage with your doctor and start with 500 milligrams or less. 

Final Thoughts

For some people, taking quercetin in supplement form isn’t necessary. They get enough of the antioxidant through a diet rich in fruits and vegetables. Individuals taking certain prescription medications and pregnant or breastfeeding women also should steer clear of quercetin supplements.

However, quercetin can be an effective supplement for those concerned about lowering their risks of terminal diseases and alleviating symptoms of inflammatory conditions. A safe short-term daily quercetin dosage is 1,000 milligrams or less.

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