Grapefruit seed extract is a liquid extracted from the seeds, pulp, and white membranes of grapefruit (Citrus paradesi). It has been a recognized antibacterial, antifungal, antiparasitic, and antiviral substance for many years. Its antimicrobial properties were extensively studied by Yugoslavian nuclear physicist Dr. Jacob Harich (1919-1996) – the first scientist who introduced the use of grapefruit seed extract as antimicrobial agent to the scientific community.
Grapefruit seed extract is composed of different flavonoids including naringin, isosacuranetin, poncirin, quercetin, campherol, neohesperidin, and apigenin. These flavonoids are actually phenolic compounds with beneficial effects to human. They work as antioxidants, neutralizing free radicals that damage body tissue and lead to heart disease, stroke, diabetes, and cancer.
Grapefruit seed extract is used as food additive, dietary supplement, cosmetic ingredient, and disinfectant. It is non-toxic, environmentally safe, cheap, and biodegradable.
Claims of antimicrobial properties of grapefruit seed extract are now being questioned. It has been found in few laboratory studies that natural grapefruit seed extract (without extraction solvents and/or preservatives) has no antimicrobial properties at all. These studies suggest that the ability of grapefruit seed extract to kill microbes is due to the preservatives and/or solvents found in it. Scientists who analyzed commercial grapefruit seed extracts found out that the extracts are contaminated with synthetic disinfectants like benzalkonium and benzethonium chlorides.
Grapefruit seed extract can help people with atherosclerosis, high blood pressure, poor blood circulation, diabetes, high cholesterol, and vision problems according to the National Center for Complementary and Alternative Medicine (NCCAM). The anti-cancer properties of grapefruit seed extract is also now being studied.
Grapefruit seed extract is labeled as GRAS (Generally Recognized as Safe) in the United States. However, there are concerns about commercial extracts contaminated with synthetic preservatives and extraction solvents.
Grapefruit seed extract contains substances that can trigger allergic reaction to human. People who are allergic to any fruit of the citrus family are likely to be allergic to grapefruit extract. Symptoms may include rashes, itching, sneezing, vomiting, nausea, diarrhea, breathing difficulty, and anaphylactic shock.
Grapefruit seed extract may also interact with certain drugs, increasing or decreasing their potency. Examples are warfarin (anticoagulant) and Lipitor (high cholesterol drug).[ad#afterpost]