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Non-Toxic Biological Approaches to the Theories,
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Our 53rd Year

A Travel Tip: Grapefruit Seed Extract


As the Northern Hemisphere moves into summer, many of us will be heading to exotic locales. But nothing can ruin a vacation faster than picking up some exotic bacteria or other assorted critters from the local water or food, leading to a case of “Montezuma’s Revenge” (a.k.a. Traveler’s Diarrhea) – a quick way to turn a dream trip into a nightmare.

So here’s a little known secret: grapefruit seed extract (GSE). In 1972, a young scientist named Jacob Harish, bit into a grapefruit seed one morning at breakfast and wondered “What makes a grapefruit seed so bitter?” This led him to discover that an extract made from the seed, pulp and white membranes of grapefruit contained elements with natural antibiotic, antifungal, antiviral, antiprotozoan, antiseptic and disinfectant properties. In 1976 Louis Parish, M.D., an Einstein Laureate physicist, and investigator for the U.S. Department of Health and Human Services and the FDA, supervised studies administering GSE to about 200 patients. He concluded that GSE “is as effective as any amebicide now available, perhaps more effective,” and “gives symptomatic relief more than any other treatment.”

GSE is available in capsule or liquid form at health food stores and many resources on the Internet, but stick with organic products only (for example: It must be “grapefruit seed extract,” not grapefruit oil or extract, not grape extract). Non-organic GSEs have been found to contain synthetic chemicals and preservatives like triclosan and methylparaben. Follow the product instructions. The liquid form dissolves faster in water than the powder. It has a bitter taste, which can be masked by adding it to a drink like orange juice. Approximately 7 drops once or twice a day should be all that is necessary to insure a healthy trip with no bowel problems. Or, take it if you think you’ve eaten or drunk something questionable, like street foods, or if you’re just feeling generally goopy on your travels.

For emergency situations, like camping, fishing, hiking out in the wilderness, GSE is a safe and simple way to disinfect water when boiling or distilling is not practical. Add the recommended number of drops to a cup or so of water and shake or stir vigorously. Let sit for a few minutes, longer if the water is cold. There will be a slightly bitter taste, but not unpalatable.

You can use GSE topically as an anti-microbial: 5-6 drops to clean toothbrushes, 30 drops in a sink to wash fruit and veggies, 15-30 drops to wash dishes and utensils. A few drops in water is an effective mouthwash. Put a few drops in water in a spray bottle for an odorless way to destroy household mold and mildew. GSE can be applied several times a day to affected areas, like athlete’s foot.

Caveat: Grapefruit and GSE are considered safe when used in normal amounts, but there is a long list of pharmaceutical drugs that can interact with grapefruit, so check with your doctor if you have any questions.


The effectiveness of processed grapefruit-seed extract as an antibacterial agent: II. Mechanism of action and in vitro toxicity. Heggers JP1, Cottingham J, Gusman J, Reagor L, McCoy L, Carino E, Cox R, Zhao JG. J Altern Complement Med. 2002 Jun;8(3):333-40.
“What are the Benefits of Grapefruit Seed Extract?” – Applied Health
“Benefits of Grapefruit Seed Extract” – Global Health Center