How long can i take quercetin

Just remember, as with all supplements, it's important to check in with your doctor first if you have questions or concerns. Keep in mind: When it comes to supporting overall immunity, quercetin should be just one component of your routine nothing works in isolation, after all. To give your immune system an extra leg up, get seven to nine hours of sleep a night, eat immune-boosting foods , consider additional expert-backed supplements for immune health , stay active, and manage stress or any existing health conditions you may have.

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She received her B. Medical review by Heather Moday, M. Heather Moday, M. Last updated on June 2, What is quercetin? Health benefits of quercetin. It may reduce the risk of viruses, from colds to herpes. It can probably help with seasonal allergies. It may help reduce chronic inflammation. It may boost cognitive function and ward off dementia. It seems to have properties that reduce the risk of cancer.

It may support cardiovascular and heart health in several key ways. Select personalised content. Create a personalised content profile. Measure ad performance.

Select basic ads. Create a personalised ads profile. Select personalised ads. Apply market research to generate audience insights. Measure content performance. Develop and improve products. List of Partners vendors. Quercetin is a chemical found naturally in a number of foods including apples, onions, teas, berries, and red wine. This flavonoid is also found in some herbs such as ginkgo biloba and St. John's wort. Quercetin acts as an antioxidant, neutralizing free radicals—the chemical by-products that harm cell membranes and damage DNA.

Available as a dietary supplement, quercetin also possesses antihistamine and anti-inflammatory properties. So far, results to support the benefits of quercetin are mixed—with some conditions examined only in test tubes or on animals. Here's how the research shakes out:. Quercetin is thought to prevent the release of histamine—an inflammatory chemical involved in allergic symptoms such as sneezing and itching—from certain immune cells.

Although lab experiments suggest that quercetin may help fight allergic conditions like allergic rhinitis , most have been performed in vitro or in animals. A review of randomized controlled trials found quercetin significantly reduced both systolic and diastolic blood pressure , particularly in diabetics who were given at least milligrams per day.

Quercetin may be no better than a placebo when it comes to enhancing athletic performance, according to a review of 11 previous studies. Another study found a more impressive link. A study analyzing 60 male students who've participated in athletics for at least three years saw improved lean body mass, total body water, basal metabolic rate, and total energy expenditure after taking quercetin.

Studies on cell cultures have shown that quercetin may help slow the growth of some types of cancer cells. Discussion threads can be closed at any time at our discretion.

Should you take quercetin for immune health? What you need to know This antioxidant, found in many foods, could boost your immune health. Mercey Livingston. Quercetin is a flavonoid that may support immune health. Getty Images Pandemic or not, supplements can be confusing.

Discuss: Should you take quercetin for immune health? Quercetin decreased histological signs of acute inflammation in the treated animals in a dose-dependent manner via suppressing leucocyte recruitment, decreasing chemokine levels and levels of the lipid peroxidation end-product malondialdehyde, and increasing antioxidant enzyme activity in experimental rat model [ 68 ].

Quercetin most likely universally suppresses the accumulation and activation of immune cells, including anti-inflammatory cells, whereas it specifically increased gene expression associated with mitochondrial oxidative phosphorylation in Western diet-induced obese mice. For the group as a whole, quercetin supplementation had no significant influence on rates of upper respiratory tract infections URTI compared to placebo.

While quercetin supplementation significantly increased plasma quercetin levels, it had no influence on measure of immune function [ 73 ]. In this study, however, there were no differences in the post-race illness rates between quercetin and placebo groups [ 75 ]. There are several studies in humans investigating the correlation of quercetin and its immunomodulatory effects.

Quercetin does indeed reduce illness after intensive exercise. Again, under double-blind conditions, Nieman et al. The literature is supportive of the anti-pathogenic capacities of quercetin when it is cultured with target cells and a broad spectrum of pathogens including URTI-related rhinoviruses, adenoviruses and coronaviruses. The impact of the co-ingestion of two or more flavonoids increases their bioavailability and the outcomes on immunity.

Nieman et al. It resulted in significantly reduced post-exercise measures for both inflammation and oxidative stress, with a chronic augmentation of granulocyte oxidative burst activity [ 77 ]. When taken together, quercetin showed a successful reduction in the illness rates of exercise-stressed athletes as well as a chronic augmentation of their innate immune function.

Most in vitro research suggests that quercetin possesses anti-inflammation and immunological improvement. The main action of quercetin on inflammation and immune function in vivo is summarized in the Table 2. Summary of the main effects of quercetin on inflammation and immune function in vivo. These results suggest that quercetin exhibited anti-inflammation and immune-enhancement in vitro cells and in vivo animals , however, studies in human did not totally support these results from cells and animals.

The effect, in which quercetin acts as an immune booster in humans, needs to be further verified for future broad application. As a widespread flavonoid, quercetin is a safe and dietary supplement based on its broad range of biological effects in animal.

The results of these effects are not consistent, however, and the outcomes need to be carefully evaluated, as they are dependent on the type of subject and their level of health. Taken together, we know definitively that a quercetin glycoside is much more efficient than other forms of quercetin.

In the majority of the literature, we find references to the benefits of prolonged supplementation with quercetin. The future challenge is to investigate optimal benefits of quercetin, especially to the recommendation for the protracted intake. For example, a carbohydrate drink may have a better effect than pure quercetin preparation. The research in this area continues to determine the proper outcomes, dosing regimen and adjuvants that may amplify any perceived bioactive effects of quercetin in vivo.

National Center for Biotechnology Information , U. Journal List Nutrients v. Published online Mar Find articles by Yao Li. Find articles by Jiaying Yao. Find articles by Chunyan Han.

Find articles by Jiaxin Yang. Find articles by Maria Tabassum Chaudhry. Find articles by Shengnan Wang. Author information Article notes Copyright and License information Disclaimer. Received Jan 25; Accepted Mar 9. This article has been cited by other articles in PMC. Abstract In vitro and some animal models have shown that quercetin, a polyphenol derived from plants, has a wide range of biological actions including anti-carcinogenic, anti-inflammatory and antiviral activities; as well as attenuating lipid peroxidation, platelet aggregation and capillary permeability.

Keywords: quercetin, inflammation, immune function, dietary sources, metabolism. Physicochemical Properties of Quercetin Quercetin is categorized as a flavonol, one of the six subclasses of flavonoid compounds. Open in a separate window. Figure 1. Dietary Sources of Quercetin Quercetin-type flavonols primarily as quercetin glycosides , the most abundant of the flavonoid molecules, are widely distributed in plants.

Absorption Quercetin glycosides might be differently absorbed based on the type of sugar attached [ 21 ]. Transformation and Transportation After absorption, quercetin becomes metabolized in various organs including the small intestine, colon, liver and kidney.

Excretion The limited research suggests that quercetin and its metabolites tend to accumulate in the organs involved in its metabolism and excretion, and that perhaps mitochondria might be an area of quercetin concentration within cells [ 36 , 37 , 38 , 39 , 40 , 41 , 42 ]. Effect of Quercetin on Inflammation and Immune Function 5. In Vitro 5. Anti-Inflammation and Promotion of Immunity Quercetin was reported as a long lasting anti-inflammatory substance that possesses strong anti-inflammatory capacities [ 43 , 44 ].

Figure 2. Table 1 Summary of the main effects of quercetin on inflammation and immune function in vitro. In Vivo 5. Animal Models Quercetin exerts inflammation and immune modulating activity in several murine models of autoimmunity. Mechanism of Action in Animal Study has shown that quercetin exerted protective effect against irradiation-induced inflammation in mice through increasing cytokine secretion [ 66 ].

Table 2 Summary of the main effects of quercetin on inflammation and immune function in vivo. Summary As a widespread flavonoid, quercetin is a safe and dietary supplement based on its broad range of biological effects in animal.

Conflicts of Interest The authors declare no conflict of interest. References 1. Davis J. Effects of the dietary flavonoid quercetin upon performance and health. Sports Med. Aguirre L. Beneficial effects of quercetin on obesity and diabetes.

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