Table of ContentsView AllTable of ContentsWhat the Research SaysPrecautionsDosage ConsiderationsGrapefruit InteractionsFrequently Asked QuestionsSources & What to Look For
Table of ContentsView All
View All
Table of Contents
What the Research Says
Precautions
Dosage Considerations
Grapefruit Interactions
Frequently Asked Questions
Sources & What to Look For
Grapefruit seed extract is made from the seed, pulp, and membranes of grapefruit and has been marketed as having antibacterial and anti-inflammatory properties with several health benefits. However, many claims about its benefits remain unfounded.
The extract is ground down and then combined withglycerin. Grapefruit seed extract (GFSE) should not be confused with grapefruit seed oil or grape seed extract (GSE). Importantly, there is a history of commercial GFSE products being contaminated with synthetic antimicrobial compounds that can be harmful in large amounts.Keep this in mind when deciding whether to purchase GFSE supplements.
In the United States, the Food and Drug Administration (FDA) does not regulate supplements the way it regulates prescription drugs. That means some supplement products may not contain what the label says. Whenchoosing a supplement, look for independently tested products and consult a healthcare provider, registered dietitian nutritionist (RD or RDN), or pharmacist.
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What the Research Says About Grapefruit Seed Extract
There are claims that grapefruit seed extract can be used to treat fungal or bacterial infections. It has been shown to have some antibacterial properties.
Many GFSE products have been found to be adulterated with the preservative benzethonium chloride, an antibacterial agent. Lab studies have indicated that the benefits related to GFSE have been due to the synthetic antibacterial agent.
However, there is no research to support any of the health claims about GSFE. In fact, there are no prospective randomized clinical trials on the effects of consuming GFSE alone in humans.
There is not a lot of information available on the safety of GFSE. Also, bear in mind there have been reports of synthetic additives in commercial GFSE products that are not listed on the product’s label.
It would be best to avoid supplements that lack safety data for pregnant and nursing individuals and children. You should also not use GFSE if you have a citrus allergy.
Speak to your primary care provider, pharmacist, or a registered dietitian nutritionist (RDN) if you are considering GFSE . They may be able to recommend alternative remedies that have fewer risks or an over-the-counter or prescription treatment, depending on your needs.
Dosage: How Much Grapefruit Seed Extract Should I Take?
There is no standard dose recommended for GFSE.
Given the lack of the research on this particular supplement, doses used in research studies are also not available.
Always speak with a healthcare provider before taking a supplement to ensure that the supplement and dosage are appropriate for your individual needs.
Grapefruit is known to interact with several medications.
Medications with grapefruit interactionsinclude but are not limited to:
Grapefruit may also interact with certain herbal medicines. Discuss your complete medication list and any supplements you take with your healthcare provider or pharmacist before adding a grapefruit-based supplement to your regimen.
Frequently Asked QuestionsNo. Grapefruit seed extract is a liquid made from the seeds, pulp, and membranes of a grapefruit. The oil is expressed from the rind of the grapefruit and is intended for use in oils, soaps, or cosmetics. The oil is typically used on the skin or as aromatherapy and is not intended to be ingested.GFSE has been promoted to fightCandida, a fungal infection that mostly occurs in and around the mouth (thrush).While GFSE has long been thought to have antifungal and antimicrobial properties, no human research supports its use for treating thrush. Nutritional supplements are also not intended to treat any disease or infection.Your best bet is to consult with a healthcare provider about evidence-based treatments for the infection.
No. Grapefruit seed extract is a liquid made from the seeds, pulp, and membranes of a grapefruit. The oil is expressed from the rind of the grapefruit and is intended for use in oils, soaps, or cosmetics. The oil is typically used on the skin or as aromatherapy and is not intended to be ingested.
GFSE has been promoted to fightCandida, a fungal infection that mostly occurs in and around the mouth (thrush).While GFSE has long been thought to have antifungal and antimicrobial properties, no human research supports its use for treating thrush. Nutritional supplements are also not intended to treat any disease or infection.Your best bet is to consult with a healthcare provider about evidence-based treatments for the infection.
GFSE has been promoted to fightCandida, a fungal infection that mostly occurs in and around the mouth (thrush).
While GFSE has long been thought to have antifungal and antimicrobial properties, no human research supports its use for treating thrush. Nutritional supplements are also not intended to treat any disease or infection.
Your best bet is to consult with a healthcare provider about evidence-based treatments for the infection.
Sources of Grapefruit Seed Extract & What to Look For
Grapefruit seed extract supplements are available as liquid concentrates, tablets, and capsules. GFSE has also been formulated in mouthwashes, drops, and other personal care products.
Some supplements contain GFSE, but others may have a mixture of extracts. It is important to read the supplement’s facts and ingredients label.
That being said, some GFSE supplements have been found to be adulterated with chemicals, such as benzethonium chloride and triclosan. These chemicals are found antibacterial soaps and cleansers and could be harmful if ingested in high doses.
Summary
Grapefruit seed extract supplements are marketed for numerous conditions, but their ability to provide any sort of benefit remains uncertain. GFSE products also carry risks of interactions with medications and potential contamination. Given this, plus the lack of any supporting research, the risks of taking these supplements likely outweigh the supposed benefits.
7 SourcesVerywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.Gafner S, Blumenthal M, Foster S, Cardellina JH 2nd, Khan IA, Upton R.Botanical ingredient forensics: detection of attempts to deceive commonly used analytical methods for authenticating herbal dietary and food ingredients and supplements.J Nat Prod. 2023;86(2):460-472. doi:10.1021/acs.jnatprod.2c00929Heggers JP, Cottingham J, Gusman J, et al.The effectiveness of processed grapefruit-seed extract as an antibacterial agent: II. Mechanism of action and in vitro toxicity[published correction appears inJ Altern Complement Med2002;8(4):521. Reagor Lana [corrected to Reagor Lee]].J Altern Complement Med. 2002;8(3):333-340. doi:10.1089/10755530260128023von Woedtke T, Schlüter B, Pflegel P, Lindequist U, Jülich WD.Aspects of the antimicrobial efficacy of grapefruit seed extract and its relation to preservative substances contained.Pharmazie. 1999;54(6):452-456.Grapefruit and drug interactions.Prescrire Int. 2012;21(133):294-298.Food and Drug Administration.Grapefruit juice and some drugs don’t mix.Seden K, Dickinson L, Khoo S, Back D.Grapefruit-drug interactions.Drugs. 2010;70(18):2373-2407. doi:10.2165/11585250-000000000-00000Roy S, Zhang W, Biswas D, Ramakrishnan R, Rhim JW.Grapefruit seed extract-added functional films and coating for active packaging applications: a review.Molecules. 2023;28(2):730. doi:10.3390/molecules28020730
7 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.Gafner S, Blumenthal M, Foster S, Cardellina JH 2nd, Khan IA, Upton R.Botanical ingredient forensics: detection of attempts to deceive commonly used analytical methods for authenticating herbal dietary and food ingredients and supplements.J Nat Prod. 2023;86(2):460-472. doi:10.1021/acs.jnatprod.2c00929Heggers JP, Cottingham J, Gusman J, et al.The effectiveness of processed grapefruit-seed extract as an antibacterial agent: II. Mechanism of action and in vitro toxicity[published correction appears inJ Altern Complement Med2002;8(4):521. Reagor Lana [corrected to Reagor Lee]].J Altern Complement Med. 2002;8(3):333-340. doi:10.1089/10755530260128023von Woedtke T, Schlüter B, Pflegel P, Lindequist U, Jülich WD.Aspects of the antimicrobial efficacy of grapefruit seed extract and its relation to preservative substances contained.Pharmazie. 1999;54(6):452-456.Grapefruit and drug interactions.Prescrire Int. 2012;21(133):294-298.Food and Drug Administration.Grapefruit juice and some drugs don’t mix.Seden K, Dickinson L, Khoo S, Back D.Grapefruit-drug interactions.Drugs. 2010;70(18):2373-2407. doi:10.2165/11585250-000000000-00000Roy S, Zhang W, Biswas D, Ramakrishnan R, Rhim JW.Grapefruit seed extract-added functional films and coating for active packaging applications: a review.Molecules. 2023;28(2):730. doi:10.3390/molecules28020730
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
Gafner S, Blumenthal M, Foster S, Cardellina JH 2nd, Khan IA, Upton R.Botanical ingredient forensics: detection of attempts to deceive commonly used analytical methods for authenticating herbal dietary and food ingredients and supplements.J Nat Prod. 2023;86(2):460-472. doi:10.1021/acs.jnatprod.2c00929Heggers JP, Cottingham J, Gusman J, et al.The effectiveness of processed grapefruit-seed extract as an antibacterial agent: II. Mechanism of action and in vitro toxicity[published correction appears inJ Altern Complement Med2002;8(4):521. Reagor Lana [corrected to Reagor Lee]].J Altern Complement Med. 2002;8(3):333-340. doi:10.1089/10755530260128023von Woedtke T, Schlüter B, Pflegel P, Lindequist U, Jülich WD.Aspects of the antimicrobial efficacy of grapefruit seed extract and its relation to preservative substances contained.Pharmazie. 1999;54(6):452-456.Grapefruit and drug interactions.Prescrire Int. 2012;21(133):294-298.Food and Drug Administration.Grapefruit juice and some drugs don’t mix.Seden K, Dickinson L, Khoo S, Back D.Grapefruit-drug interactions.Drugs. 2010;70(18):2373-2407. doi:10.2165/11585250-000000000-00000Roy S, Zhang W, Biswas D, Ramakrishnan R, Rhim JW.Grapefruit seed extract-added functional films and coating for active packaging applications: a review.Molecules. 2023;28(2):730. doi:10.3390/molecules28020730
Gafner S, Blumenthal M, Foster S, Cardellina JH 2nd, Khan IA, Upton R.Botanical ingredient forensics: detection of attempts to deceive commonly used analytical methods for authenticating herbal dietary and food ingredients and supplements.J Nat Prod. 2023;86(2):460-472. doi:10.1021/acs.jnatprod.2c00929
Heggers JP, Cottingham J, Gusman J, et al.The effectiveness of processed grapefruit-seed extract as an antibacterial agent: II. Mechanism of action and in vitro toxicity[published correction appears inJ Altern Complement Med2002;8(4):521. Reagor Lana [corrected to Reagor Lee]].J Altern Complement Med. 2002;8(3):333-340. doi:10.1089/10755530260128023
von Woedtke T, Schlüter B, Pflegel P, Lindequist U, Jülich WD.Aspects of the antimicrobial efficacy of grapefruit seed extract and its relation to preservative substances contained.Pharmazie. 1999;54(6):452-456.
Grapefruit and drug interactions.Prescrire Int. 2012;21(133):294-298.
Food and Drug Administration.Grapefruit juice and some drugs don’t mix.
Seden K, Dickinson L, Khoo S, Back D.Grapefruit-drug interactions.Drugs. 2010;70(18):2373-2407. doi:10.2165/11585250-000000000-00000
Roy S, Zhang W, Biswas D, Ramakrishnan R, Rhim JW.Grapefruit seed extract-added functional films and coating for active packaging applications: a review.Molecules. 2023;28(2):730. doi:10.3390/molecules28020730
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