6 Grapefruit Seed Extract Benefits & How to Use

When you eat a grapefruit, what do you do with the seeds? I’m guessing you spit them out or remove them from the start. What if I told you that those grapefruit seeds, particularly in grapefruit seed extract (GSE) form, actually might hold a wealth of health benefits.

While grapefruit seed extract features a different set of benefits than the flesh of grapefuit, it does overlap with the incredible abilities of grapefruit essential oil. Practitioners of alternative medicine say grapefruit seed extract possesses antibacterial, antiviral and antifungal properties and recommended its use for many issues, such as candida, earaches, throat infections and diarrhea.

Grapefruit seed extract, especially when used internally, can be somewhat of a controversial supplement due to a lack of human studies as well as evidence of adulteration of grapefruit seed extract. The main controversy stems from study findings that some commercially produced grapefruit seed extracts contain harmful ingredients like benzethonium chloride and triclosan.

Without a doubt, if you’re going to use a grapefruit seed extract product, you should always read ingredients lists carefully and make sure that you buy from a reputable company. You should also consult with your healthcare professional.

So are the seeds of a grapefruit actually good for you?

What Is Grapefruit Seed Extract?

Grapefruit seed extract, also known as GSE or citrus seed extract, is derived from the seeds, pulp and white membranes of a grapefruit. Grapefruit (Citrus paradisi) seeds comes from a grapefruit, which comes from a grapefruit tree. This is a citrus tree of the Rutaceae family that produces edible fruit.

Grapefruit seed extract is made by mixing grapefruit seeds and pulp into a highly acidic liquid. After some additional processing, the mixture turns into a yellow, thick liquid that has a strong, bitter taste. It’s then typically combined with vegetable glycerin to reduce the bitterness and acidity.

The main biological compounds in a grapefruit seed that are believed to be responsible for its ability to destroy infectious invaders are the polyphenols known as limonoids and naringenin.

You can also get the benefits of GSE by eating the seeds, pulp and white membranes of a grapefruit. The benefits of grapefruit juice are increased when it’s produced fresh including the seeds and membranes.

Benefits

1. Inhibits candida

Candidiasis, commonly referred to as “candida,” is a fungal infection that can affect men and women of all ages in various parts of the body. It most commonly occurs in the mouth, ears, nose, toenails, fingernails, gastrointestinal tract and vagina. Grapefruit seed extract may belong on a candida diet plan, as studies indicate that GSE can effectively inhibit Candida albicans.

A Polish study found that a 33 percent grapefruit extract has a potent antifungal effect against Candida albicans strains taken from patients with candida symptoms. GSE’s antifungal properties help it combat candida infestations by killing the yeast cells that have taken over in the body.

2. Fights antibiotic-resistant UTIs

A noteworthy case study published in the Journal of Alternative and Complementary Medicine found that grapefruit seeds were highly effective in killing antibiotic-resistant urinary tract infections. The study looked at several patients who were treated with grapefruit seeds (Citrus paradisi) orally for two weeks. The dosage was five to six grapefruit seeds every eight hours.

Within those two weeks, all patients responded satisfactorily to the treatment minus one. However, this patient initially had the bacterial UTI resistant to three different antibiotics, but after taking grapefruit seed there was a reversal of the antibiotic resistance pattern.

Although a small human study, the data points toward the antibacterial ability of dried or fresh grapefruit seeds being comparable to antibacterial drugs, making it an effective home remedy for UTIs. In fact, a 2021 study concluded that GSE was a naturally derived antibacterial substance that worked as a antibacterial agent, even at a very low concentration.

3. May relieve digestive issues

One preliminary human trial investigated the effectiveness of grapefruit seed extract on atopic eczema patients who also had intestinal dysbiosis, a microbial imbalance or maladaptation in the digestive tract.

All patients showed severe atopic eczema, including bleeding lesions over the face, limbs and trunk, while 14 of 25 also had intermittent diarrhea, constipation, flatulence, intestinal rushes, bloating and abdominal discomfort.

Subjects received either two drops of a 0.5 percent liquid concentrate of grapefruit seed extract twice a day or 150 milligrams of encapsulated grapefruit seed extract (ParaMicrocidin®) three times a day. After a month, all of the subjects taking capsules experienced significant improvements in constipation, flatulence and abdominal discomfort, as well as night rest, while 20 percent of the subjects taking the liquid experienced significant improvements in their negative digestive symptoms. The extract was mostly effective against Candida, Geotrichum sp. and hemolytic E. coli. There were not any registered side effects during the entire study.

4. Works as a general antimicrobial

Grapefruit seed extract benefits can be experienced when it’s taken by mouth for bacterial, viral and fungal infections, including yeast infections. A 2023 study published in the Journal of Agricultural and Food Chemistry showed that in combination with cinnamon oil, GSE helped prevent oral bacteria with or without the presence of other food ingredients.

There are also many grapefruit seed uses that don’t involve ingesting the extract. Due to its antimicrobial activities, grapefruit seed extract is commonly included in many throat sprays, nasal sprays, ear drops, mouth washes, toothpastes, shower gels, wound disinfectant sprays and other personal care products. Instead of using unnatural and synthetic preservatives, many natural companies turn to grapefruit seed extract for its ability to preserve a product by killing unwanted bacteria.

5. May inhibit Staphylococcus aureus and Escherichia coli

Widely used in the food industry to preserve foods, few studies have addressed how it works against the biofilm-forming strains of Staphylococcus aureus and Escherichia coli. A 2019 study suggested that GSE may be useful as a anti-biofilm agent for both of these strains.

In addition, a 2019 study demonstrated that grapefruit seed extract mixed with distilled water inhibited avian pathogens and other viruses and bacteria. After spraying, it was shown to be effective even within a short contact time.

6. May relieve athlete’s foot and nail fungus

Athlete’s foot is a skin disease that usually occurs between the toes and is caused by a fungus. As a natural treatment for athlete’s foot, you can try applying full-strength grapefruit seed extract to the problem areas two to three times per day.

You can also use GSE as an alternative to tea tree oil to treat toenail fungus. Simply paint the extract on the infected nails twice a day until you see improvement.

How to Use

Grapefruit seed extract is available in supplement form as a liquid concentrate, capsule or tablet. It’s readily available at your local health store or online.

Never purchase a grapefruit seed extract product that contains health-hazardous, synthetic chemicals like methylparaben, benzethonium chloride or triclosan. A recommended formula contains just two ingredients: grapefruit seed extract and vegetable glycerin.

Always speak with your healthcare professional about proper dosage or follow the instructions provided on the extract.

The typical recommended dosage for the liquid extract is 10 to 12 drops in a glass of water (at least five ounces), one to three times daily. For capsules and tablets containing dried grapefruit seed extract, the usual recommendation is 100 to 200 milligrams, one to three times daily. The amount depends on the strength of the GSE and the reason you’re taking it.

Grapefruit seed extract can deplete good bacteria in the gut if it’s taken for long periods of time. If you intend to take it for three or more consecutive days, make sure to also consume a probiotic supplement a few hours before taking your dose of GSE.

Other antimicrobial uses of grapefruit seed extract include:

• In laundry — to kill fungi and bacteria, add 10 to 15 drops to the final rinse
• In carpet cleaners — to kill pathogenic organisms
• In nebulizers — one drop GSE to one ounce saline water for control of respiratory infections
• In humidifiers — three to four drops per gallon of water to prevent algae growth
• As a better preservative than most chemical preservatives currently on the market
• Disinfecting surfaces — when mixed with water in a spray bottle, it’s great for disinfecting cutting boards and other kitchen as well as bathroom surfaces
• In hot tubs and swimming pools — GSE is added to lessen the need for high levels of chlorine
• Farming — farmers use the extract in animal feed and water to reduce the incidence of infectious diseases

Always store your grapefruit seed extract away from heat and direct light.

If you feel unsure about taking supplemental forms of grapefruit seed, you can also eat the seeds (warning: they’re bitter) and white membranes of the grapefruit. You can also include the seeds and membranes when you make fresh grapefruit juice.

Potential Side Effects and Caution

Before using grapefruit seed extract, talk to your healthcare professional if you:

• are currently taking any other medications, especially blood thinners or medicines used after organ transplant
• are allergic to any medicine (prescription or over-the-counter or dietary supplements)
• are pregnant or plan to become pregnant while using this medicine
• are breast-feeding
• have any other health problems, such as high blood pressure or heart/blood vessel disease

Never put the extract into your eyes, and don’t use at full strength in your mouth, ears, nose or sensitive areas. If used in full strength on skin it may cause irritation.

See a healthcare professional right away if you have any signs of a serious allergic reaction after taking GSE. Signs of an allergic reaction include swelling in your face or hands, swelling or tingling in your mouth or throat, chest tightness, trouble breathing, hives or rash.

Grapefruit seed extract is not commonly known to cause any side effects when taken as directed. However, rare side effects of may include nausea, vomiting, swollen or painful tongue, and burns of the mouth, throat or stomach. Discontinue use if you exhibit any negative side effects.

Conclusions

• Grapefruit seed extract, also known as GSE or citrus seed extract, is derived from the seeds, pulp and white membranes of a grapefruit.
• Many professionals, including doctors, veterinarians, farmers and consumers, praise GSE’s multipurpose use and effectiveness.
• Grapefruit seed extract has been shown to possess antibacterial, antiviral, antimicrobial and antifungal properties, and it fights candida, kills antibiotic-resistant UTIs, remedies fungal infections, relieves athletes foot and nail fungus, and treats digestive disturbances associated with eczema.
• If you have candida, it’s best to begin GSE therapy in partnership with a cleansing anti-candida diet. This means avoiding things like sugar, alcohol, dairy and grains.
• Never buy a grapefruit seed extract product that contains harmful ingredients like benzethonium chloride, triclosan or methylparaben.