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.
Irritable Bowel Syndrome
Refer to label instructions
In one study, grapefruit seed extract improved IBS symptoms in 20% of people taking the liquid, while all of the patients taking capsules noted definite improvement of constipation, flatulence, abdominal discomfort, and night rest.
A preliminary trial investigated the effectiveness of grapefruit seed extract in people with eczema and symptoms of IBS.1 Participants received either 2 drops of a 0.5% oral solution of grapefruit seed extract twice daily or 150 mg of encapsulated grapefruit seed extract three times daily. After a month, IBS symptoms had improved in 20% of those taking the liquid, while all of the patients taking capsules noted definite improvement of constipation, flatulence, abdominal discomfort, and night rest. These results need confirmation in double-blind trials.
The typical recommendation for the liquid concentrate is 10–12 drops in 6–7 ounces of water one to three times daily. For capsules and tablets containing dried grapefruit seed extract, the usual recommendation is 100–200 mg one to three times daily.
Grapefruit seed extract is available in liquid concentrate and in capsules and tablets.
Grapefruit seed extract is not an essential nutrient and no deficiency states have been reported.
Certain medicines interact with this supplement.
In case reports, ingestion of grapefruit seed extract interfered with the effect of warfarin.2 This inhibitory effect appeared to be due to benzethonium chloride, a synthetic preservative that is added to most grapefruit seed extract products.
1. Ionescu G, Kiehl R, Wichmann-Kunz F, et al. Oral citrus seed extract in atopic eczema: In vitro and in vivo studies on intestinal microflora. J Orthomol Med 1990;5:155–8.
2. Brandin H, Myrberg O, Rundlof T, et al. Adverse effects by artificial grapefruit seed extract products in patients on warfarin therapy. Eur J Clin Pharmacol 2007;63:565–70.
Last Review: 05-01-2013
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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 2014.
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