The Health Benefits of Grapefruit Seed Extract (GSE)     


       Grapefruit Seed Extract (aka as citrus seed extract) is made from the seeds, pulp and membranes of grapefruit.  The constituents of GSE that appear to give it the medicinal qualities it is known for are two polyphenols known as limonoids and naringenin. These components of GSE have been shown to be effective in the treatment of candidiasis (a yeast/fungus), a variety of pathogenic fungal, parasitic, and bacterial organisms and even some viral organisms. 

GSE and candidiasis:

       GSE was discovered back in 1980 by American immunologist Jacob Harich. In a Polish study published in 2001, a number of strains of Candida albicans were shown to be killed off by GSE. Back in the early 1990’s I attended a lecture given by medical doctor Leo Galland of New York and remember him saying that GSE killed five strains of Candida whereas some medications used for such purpose killed only three stains. Dr Galland reported that in treating 297 patients with GSE, there were only two patients who did not have a positive outcome. 

GSE and bacteria:

       In various cell based studies, GSE inhibited over 60 strains of bacteria and yeasts. It was found to be effective against food borne pathogens such as Salmonella. GSE has also been found to be effect against E.Coli, Staph and Strep pathogens.  In a study published in 2005 in the Journal of Alternative and Complementary Medicine, it was discovered that grapefruit seeds were very effective in killing antibiotic resistant urinary tract infections.      

       In a 2002 study published in, sixty-seven bacterial agents were exposed to GSE and five commonly used topical meds used against these bacterial agents. The result was that GSE was consistently antibacterial against all sixty-seven organisms tested.  The authors of the study concluded that the antibacterial characteristics of GSE are comparable to that of proven topical antibacterial meds and that GSE having comparative effectiveness against a wide range of bacterial agents is significant. 

       GSE, because of its fungus fighting ability, has also been shown to be an effective topical application to use against fungal infections such as athlete’s foot, jock itch and ringworm.  

GSE and diabetes:

       Because of its successful use in Africa in the treatment of diabetes, a rat study was conducted to test the use of GSE in treating diabetes. This study was posted on in 2008.  In this study, medically induced diabetic rats were treated with GSE with the results being comparable to the popular Type 2 diabetic drug Metformin.  The rats given GSE also showed reductions in LDL cholesterol while a raise in HDL cholesterol (the good guys). This study concluded with the statement: “Results of this study lend support to the traditional use of grapefruit seeds in the management of type 1 diabetic patients and may suggest a role in orthodox management of the disease.”

GSE and viruses:

       In a 2019 study published in the Journal of Veterinarian Medical Science, it was determined that GSE was effective against the avian influenza virus (AIV) and several other viruses that attack poultry and other farm animals. While these are viruses that do not normally attack humans, it is noteworthy that GSE was effective against these viruses. Research needs to be done to determine the effectiveness of GSE against viruses that attack humans.


       We have carried GSE at Milk ‘N Honey for many years from the company NutriBiotic. Over the years we have had much positive feedback on the effectiveness of this product.  We have effectively used it for many years in our family for everything from the common cold and sore throats to the flu and various intestinal problems.

       GSE comes in both a 2 and 4 fluid ounce container and is also available as a nasal spray and in capsules.