Quercetin: Health Benefits, Dosage, & Side Effects

A plant pigment is known as quercetin (flavonoid). 

Red wine, onions, green tea, apples, berries, Ginkgo biloba, St. John’s wort, American elder, and many more plants and foods contain it. 

Quite a bit of quercetin may be found in buckwheat tea. Quercetin is a medication that people use.

Heart and blood vessel diseases including “hardening of the arteries” (atherosclerosis), excessive cholesterol, heart disease, and circulation issues are all treated with quercetin. 

Inflammation, asthma, gout, viral infections, schizophrenia, diabetes, cataracts, hay fever, peptic ulcers, schizophrenia, chronic fatigue syndrome (CFS), cancer prevention, and treating chronic prostate infections are some conditions for which it is utilized. 

Athletes can use quercetin to strengthen their endurance and perform better.

What is Quercetin?

The pigment quercetin is a member of the flavonoids class of plant chemicals.

Flavonoids can be found in:

• Vegetables
• Fruits
• Grains
• Tea
• Wine

Numerous health advantages have been associated with them, such as lowered chances of cancer, heart disease, and degenerative brain problems.

Flavonoids, such as quercetin, have positive benefits because they act as antioxidants in your body.

Compounds known as antioxidants have the ability to bind to and neutralize free radicals.

Free radicals are unstable chemicals that, if present in excessive amounts, can harm cells.

Free radical damage has been related to a number of chronic diseases, such as diabetes, heart disease, and cancer (4Trusted Source).

How to Take Quercetin

Children should not take quercetin, according to the available research.

Adult

Depending on the illness being treated, different adult doses of quercetin are suggested.

Precautions

In general, quercetin is regarded as secure. An upset stomach and a headache are possible side effects. 

According to preliminary research, a byproduct of quercetin may result in the loss of protein function. 

Quercetin kidney damage can occur at extremely high dosages. You should occasionally stop taking quercetin.

Avoid quercetin if you have a renal illness, are pregnant, or are nursing.

There have been instances of renal injury at dosages of more than 1 g daily.

How Does Too Much Quercetin Affect Me?

Always adhere to the manufacturer’s suggested dose as a general rule. 

Excess can cause a severe imbalance in the human body making you extremely sick.

Call your healthcare professional and discontinue taking quercetin if you encounter any negative effects.

Quercetin Benefits

Potentially helpful for swelling and discomfort in the prostate (inflammation). 

In males with persistent prostate issues that aren’t caused by infection, oral quercetin administration tends to lessen discomfort and enhance the quality of life. 

Still, it doesn’t appear to assist with urination issues.

Inadequate Data to Assess Effectiveness for Heart Disease 

Consuming foods high in quercetin, such as tea, onions, and apples, may lower the risk of heart disease-related mortality in senior men, according to some studies. 

Another preliminary study, however, indicates that daily quercetin supplementation does not reduce risk factors for heart disease.

Elevated Cholesterol

Low-density lipoprotein (LDL) cholesterol, total cholesterol, or high-density lipoprotein (HDL) cholesterol do not appear to be affected by the short-term use of quercetin supplements.

Elevated Blood Pressure 

According to some studies, patients with untreated, moderately high blood pressure may have a slight (5-7 mmHg) drop in blood pressure after taking 365mg of quercetin aglycone twice a day. We don’t yet know how significant this is.

Infections in the lungs are brought on by exercise. 

Taking 500 mg of quercetin twice a day for three weeks prior to and continuing during three days of extended, intensive cycling has been shown to minimize the incidence of upper respiratory infections in the 14 days following the strenuous activity.

Transplanting a Kidney

According to some studies, 20 mg of quercetin and 480 mg of curcumin, given once or twice daily beginning 24 hours after a kidney transplant and continuing for a month, together with anti-rejection medications, improve the transplanted kidney’s early function.

Lung Tumors 

According to several studies, eating a diet high in quercetin may lower the risk of getting lung cancer, particularly in males who smoke.

Cystitis Interstitial

Flavonoids may be beneficial for interstitial cystitis sufferers, according to two small trials. 

People who have this disorder frequently feel the urgent need to pee and have bladder discomfort that is comparable to a bladder infection. 

In both trials, participants who took a quercetin-containing supplement seemed to experience less symptoms. 

Other flavonoids were nonetheless included in the trials. 

Therefore, it is unknown which flavonoid provides the greatest advantages. It is necessary to do more and better studies.

Prostatitis

According to preliminary research, quercetin may lessen the signs and symptoms of prostatitis or inflammation of the prostate. 

Males who took quercetin had fewer symptoms than men who took a placebo, according to small research. More study is required.

Arthritis Rheumatoid (RA)

People with RA have reportedly reported reduced symptoms after switching from a standard Western diet to one high in uncooked berries, fruits, vegetables, nuts, roots, seeds, and sprouts that are packed with antioxidants like quercetin.

However, there is no proof that the beneficial benefits were caused specifically by antioxidants, and there is also no proof that quercetin supplements may cure RA.

Side Effects of Quercetin

When used orally in small doses, quercetin is POSSIBLY SAFE for the majority of individuals. 

It is safe to take up to 500 mg of quercetin twice daily for 12 weeks. The safety of longer-term usage or higher dosages is unknown.

• Headaches and tingling in the arms and legs are side effects of quercetin. 
• Kidney damage might occur at extremely high dosages.
• Quercetin is POSSIBLY SAFE when administered intravenously (by IV) in the recommended dosages (less than 722 mg). 
• However, giving IVs of bigger doses may not be safe. At larger dosages, instances of renal injury have been made.

What are the Risks of Taking Quercetin?

The use of quercetin as food is probably secure. If you use quercetin as a supplement in moderation for a brief period of time, such as 500 mg twice a day for 12 weeks, it could be safe. 

Longer-term dangers aren’t understood.

Adverse Consequences 

Taking quercetin may result in a headache or tingling in the arms and legs. If you receive an IV dose of quercetin, you might experience additional adverse effects (intravenously).

Risks

High dosages have the potential to harm the kidneys. Do not use quercetin as a supplement if you are expecting or nursing. Given how many foods contain quercetin, you could consume too much.

f you are taking medications that are altered by the liver, such as antibiotics, cyclosporine, warfarin, or other medications, use caution. 

The possibility of adverse effects is increased by quercetin, which may alter how these medications function.

Quercetin doesn’t seem to interact with any meals, other herbs, or supplements.

Supplements are not subject to FDA regulation. 

Even if they are natural vitamins, make sure to let your doctor know about them. 

Your doctor can next examine any possible adverse effects or interactions with foods, drugs, other herbs, or dietary supplements. 

If the supplement could increase your risks, they can let you know.

How to Take quercetin

Dosing. Adults have taken quercetin most frequently at oral dosages of 250–1000 mg daily for up to 12 weeks. 

Find out from a healthcare professional what dosage might be appropriate for your situation.

How Long Does it Take for Quercetin to Work

Only two studies that had a minimum 6-week treatment period and assessed the effects of quercetin on human endurance performance could be located. 

Following 6 weeks of supplementation, MacRae and Mefferd7 discovered a 3% improvement in bike time trial performance.

How Much Quercetin Per Day 

Dosing. Adults have taken quercetin most frequently at oral dosages of 250–1000 mg daily for up to 12 weeks. 

Find out from a healthcare professional what dosage might be appropriate for your situation.

WARNINGS & SPECIAL PRECAUTIONS

Breastfeeding and becoming pregnant 

The usage of quercetin during pregnancy and breastfeeding is not well understood. 

Avoid usage to be on the safe side.

What Dosage of Quercetin Should I Take?

It’s crucial to take quercetin supplements according to your doctor’s recommendations if you think you could benefit from them. 

Quercetin supplements are often used in amounts ranging from 250 to 1,000 mg. 

Daily dosages of 1 gram (g) may be used safely in certain persons. Daily oral supplementation is required for up to 12 weeks at a time. proper up arrow

Tennant advises taking quercetin for therapeutic purposes more moderately than the previously suggested dosage: of 500 mg, one to two times per day. 

Tennant also advises speaking with your doctor before using quercetin supplements for a period longer than four weeks. 

She claims that “safety in high dosages for longer times has not yet been determined.”

Drug and Supplement Interactions with Quercetin

Despite the fact that quercetin is not known to interact with any foods, these supplements may reduce the effectiveness of some drugs.

Proper up arrow. There are a number of interactions between supplements and medications to be aware of, including the following: proper up arrow

Anti-diabetic drugs, which may result in abrupt decreases in blood sugar levels

Drugs used to treat hypertension that might cause low blood pressure

• Cyclosporine
• Diclofenac, a drug used topically and taken orally, is used to treat arthritis.
• herbs or dietary supplements that reduce blood sugar, like chromium
• herbs or dietary supplements that reduce blood pressure, such as niacin and L-arginine
• Midazolam, Quinolone antibiotics, and Pravastatin
• Quetiapine \s Warfarin

Where to Buy Quercetin 

Here are some quick places to purchase Quercetin!

They will reach your doorstep in no time!

1. Solgar Quercetin Complex with Ester-C Plus
2. Sandhu’s Quercetin 1000mg
3. Zinc Quercetin 120 Vegetarian Capsules
4. Quercetin 500mg Supplement 
5. Jarrow Formulas Quercetin
6. NOW Supplements Quercetin with Bromelain
7. Amazing Formulas Quercetin
8. Naturebell Quercetin 1000mg
9. Quercetin Phytosome Vitamin C and Zinc Capsules
10. Solaray Quercetin Bromelain & Vitamin C

Overview

Natural sources of the plant chemical quercetin include apples, tea, onions, and other meals and beverages. 

The FDA typically deems it acceptable for use in foods up to 500 milligrams per serving when used as an ingredient.

Anti-inflammatory and antioxidant properties of quercetin are considered to exist. 

Although quercetin has been examined for a number of medical diseases, further study is still required before it can be used for any medical condition. 

Despite being usually safe, quercetin can interact with a variety of drugs and dietary supplements, so it’s crucial to consult your doctor before using it.