What Are Star Ratings?
Our proprietary “Star-Rating” system was developed to help you easily understand the amount of scientific support behind each supplement in relation to a specific health condition. While there is no way to predict whether a vitamin, mineral, or herb will successfully treat or prevent associated health conditions, our unique ratings tell you how well these supplements are understood by the medical community, and whether studies have found them to be effective for other people.
For over a decade, our team has combed through thousands of research articles published in reputable journals. To help you make educated decisions, and to better understand controversial or confusing supplements, our medical experts have digested the science into these three easy-to-follow ratings. We hope this provides you with a helpful resource to make informed decisions towards your health and well-being.
3 Stars Reliable and relatively consistent scientific data showing a substantial health benefit.
2 Stars Contradictory, insufficient, or preliminary studies suggesting a health benefit or minimal health benefit.
1 Star For an herb, supported by traditional use but minimal or no scientific evidence. For a supplement, little scientific support.
This supplement has been used in connection with the following health conditions:
How It Works
How to Use It
Flavonoid supplements are not required to prevent deficiencies in people eating a healthy diet. Healthcare practitioners commonly recommend 1,000 mg of citrus flavonoids taken one to three times per day. Alternatively, 240–600 mg of bilberry (standardized to 25% anthcyanosides) may be taken per day.
Where to Find It
Flavonoid deficiencies have not been reported.
Interactions with Supplements, Foods, & Other Compounds
The flavonoids work in conjunction with vitamin C . Citrus flavonoids, in particular, improve the absorption of vitamin C.81 , 82
Interactions with Medicines
Certain medicines interact with this supplement.
Types of interactions: Beneficial Adverse Check
Replenish Depleted Nutrients
Reduce Side Effects
Potential Negative Interaction
The Drug-Nutrient Interactions table may not include every possible interaction. Taking medicines with meals, on an empty stomach, or with alcohol may influence their effects. For details, refer to the manufacturers’ package information as these are not covered in this table. If you take medications, always discuss the potential risks and benefits of adding a supplement with your doctor or pharmacist.
No consistent side effects have been linked to the flavonoids except for catechin, which can occasionally cause fever, anemia from breakdown of red blood cells, and hives .85 , 86 These side effects subsided when treatment was discontinued.
In 1980, quercetin was reported to induce cancer in animals.87 Most further research did not find this to be true, however.88 , 89 While quercetin is mutagenic in test tube studies, it does not appear to be mutagenic in animal studies.90 In fact, quercetin has been found to inhibit both tumor promoters91 and human cancer cells.92 People who eat high levels of flavonoids have been found to have an overall lower risk of getting a wide variety of cancers,93 though preliminary human research studying only foods high in quercetin has found no relation to cancer risk one way or the other.94 Despite the confusion, in recent years experts have shifted their view of quercetin from concerns that it might cause cancer in test tube studies to guarded hope that quercetin has anticancer effects in humans.95
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Last Review: 11-07-2012
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The information presented in Aisle7 is for informational purposes only. It is based on scientific studies (human, animal, or in vitro), clinical experience, or traditional usage as cited in each article. The results reported may not necessarily occur in all individuals. For many of the conditions discussed, treatment with prescription or over the counter medication is also available. Consult your doctor, practitioner, and/or pharmacist for any health problem and before using any supplements or before making any changes in prescribed medications. Information expires June 2013.
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