Key takeaways
Quercetin is a dietary flavonoid, a type of natural plant pigment that helps to give fruits, vegetables, and flowers their color. It’s found in foods and available as a supplement.
The recommended dose as a supplement is 500 mg to 1,000 mg. It’s more effective when taken alongside vitamin C, bromelain, and healthy fats, such as olive oil.
Taking higher doses can increase your risk of side effects.
Quercetin is a flavonoid, a type of natural plant pigment that helps to give fruits, vegetables, and flowers their color. Flavonoids like quercetin are polyphenols, a type of antioxidant with the additional benefit of anti-inflammatory effects. Antioxidants neutralize free radicals that would otherwise cause damage in your body, increasing the risk of conditions like heart disease, cancer, or diabetes. Quercetin is found in the highest concentrations in foods such as capers, onions, apples, berries, grapes, red wine, green tea, and citrus fruits. It’s also available as a supplement. For healthy adults, a daily intake of 500 mg to 1,000 mg of quercetin is generally recommended. This dosage range is considered safe and effective, particularly when taken in combination with a balanced, nutritious diet.
How much quercetin should you take daily?
Thanks to its antioxidant properties, quercetin has many potential benefits, such as lowering blood pressure, reducing the risk of cardiovascular disease, improving cholesterol, preventing allergies, killing cancer cells, aiding muscle recovery, and even the potential to prevent neurodegenerative disorders like Alzheimer’s disease.
It’s important to note that taking quercetin supplements will not give you instant relief. “In reality, the beneficial effects of quercetin may take time to manifest and may vary depending on individual circumstances,” Sean Ormond, MD, a physician based in Phoenix, Arizona. Be patient when starting a new dietary supplement.
Can you take too much quercetin?
Exceeding 1,000 mg of quercetin supplements daily can lead to potential side effects such as headaches, nausea, and tingling sensations in the limbs. In other words, even though quercetin is found in food and the supplements are sold over the counter, it’s possible to consume too much.
“A common misconception is that because quercetin is a natural compound found in common foods, it must be completely safe to consume in supplement form,” explains Dr. Ormond. “While natural sources of quercetin are generally safe, concentrated doses in supplement form may have different effects and potential risks.”
Specifically, very high doses of quercetin have been investigated for their potential to cause kidney damage and hair loss (though research on hair loss as a direct consequence of excessive quercetin intake is limited). To avoid adverse effects of quercetin supplementation, it’s crucial to adhere to recommended dosages and consult with a healthcare provider, especially when considering higher or more frequent doses.
When is the best time of day to take quercetin?
You can take quercetin at any time of day. However, you should consider taking it at mealtimes because foods containing vitamin C, bromelain, and healthy fats can aid its absorption. Additionally, “some individuals may prefer to take it with meals to minimize potential gastrointestinal discomfort,” says Dr. Ormond. Taking quercetin on an empty stomach can increase the risk of potential side effects such as nausea. Plus, syncing your dose with your breakfast or dinner makes it part of your daily routine, which can help with consistency—an important part of any supplement’s effectiveness. It won’t work if you don’t remember to take it.
Who should not take quercetin supplements?
People taking certain medications or with certain health conditions should not take quercetin.
Quercetin can interact with some common drugs. Notably, it may enhance the effects of blood thinners like warfarin, raising bleeding risks. It can affect the metabolism of medications processed by the cytochrome P450 enzyme system, including certain antibiotics (like ciprofloxacin) and chemotherapy agents.
People with kidney disease or those pregnant or breastfeeding are advised against using quercetin due to potential risks and the lack of safety data.
Bottom line
Overall, the recommended daily intake of 500 mg to 1,000 mg—especially when paired with vitamin C, bromelain, and healthy fats—optimizes its effectiveness while minimizing potential side effects associated with higher doses. However, individuals should exercise caution and consult healthcare professionals before starting supplementation to navigate any possible interactions or contraindications based on personal health conditions or medication use. With mindful incorporation into one’s routine and adherence to advised dosages, quercetin can be a valuable addition to achieving overall wellness.
Sources
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