Health Benefits of Grapefruit Seed Extract

Extracts from grapefruit seeds sometimes referred to as citricidal – the bioactive bioflavonoid compound – is known for its powerful anti-microbial, anti-fungal and anti-bacterial activity. But considering we don’t eat the seeds of grapefruits; we investigate how this extract is turned into a food supplement and the evidence for its use.

Grapefruit Seed Extract Production

Grapefruit seed extract (GSE) containing citricidal is processed from grapefruit seeds and pulp obtained as a by-product from grapefruit juice production. In premium products, only vegetable glycerine is added to the final product to reduce acidity and bitterness before the extract is encapsulated in vegetarian capsules. Third-party testing of products should also be present to determine that the food supplements are free of contaminants, as well as free from soya, dairy and gluten. These whole GSE extracts also contain other essential oils and antioxidants.

Grapefruit Seed Extract Benefits:

1. Antimicrobial & Anti-fungal

Grapefruit seed extract contains potent compounds that can kill more than 60 types of bacteria and yeasts. In vitro studies have shown that it can even be as effective as some commonly prescribed topical antifungal and antibacterial medications, such as nystatin.

GSE kills bacteria by disrupting the membranes inside the cells by preventing the uptake to nutrients (e.g. amino acids) causes the cell membranes to swell and burst after just 15 minutes of exposure.

GSE has a different mechanism of action in killing yeast cells (by apoptosis, a process in which cells self-destruct), which is still as very effective anti-fungal action. Popular uses of this food supplements (both as a topical solution and internal application through capsules) include as part of thrush and anti-candida programmes.

2. Antioxidants

GSE is rich in essential oils, vitamin E, flavonoids and polyphenols, which all act as antioxidants.The polyphenol naringin is found in very high concentrations in grapefruit seeds and is what gives grapefruit its bitter taste. This important phytonutrient has strong antioxidant abilities and has been found to protect tissues against radiation damage.

3. Stomach Health

Preliminary studies have found that GSE can protect the stomach lining from damage caused by alcohol and stressby increasing blood flow to the area and preventing damage caused by free radicals ultimately leading to ulcers and lesions.

One study also suggests that GSE kills the bacterium H. pylori, which is one of the major causes of stomach inflammation and ulcers. These studies are in very early stages as to how this translates into human medicine but its promising research for a natural medicine approach to stomach ulcers.

4. Urinary Tract Infections (UTIs)

Since GSE is so effective at killing bacteria, researchers have begun to investigate whether it can treat infections in humans. One very small study found that eating six grapefruit seeds every eight hours for two weeks effectively treated urinary tract infections in some people.

Now were the first to admit that this study of just four people does not translate into clinical evidence for a population but it does help uncover some of the mechanisms of action of this natural plant extract and leads to the hypothesis that the well-known antioxidants and antimicrobial compounds in grapefruit seeds can help your body fight off infectious bacteria including those in the urinary tract.

5. Heart Health

Preliminary studies using GSE suggest these supplements can improve cardiovascular disease risk factors (including blood sugar imbalances and insulin resistance as well as cholesterol levels) and so potentially reducing the chances of developing heart disease. One study even found that GSE was as effective as the drug metformin in reducing blood sugar levels models of diabetes.

6. Blood Vessel Protection

When blood flow is the cardiovascular system is restricted, such as in cases of blood clots or stroke, cells in the affected area become damaged and may die. Some studies suggest that grapefruit seed extract supplements can help reduce the severity of this type of damage due to its powerful antioxidants and its ability to increase blood flow to tissues.

In summary, a good quality GSE supplement is an excellent addition to an anti-candida anti-fungal programme and has potential for supporting several other areas of health though clinical research is still in its infancy.


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Elisabeth Philipps

Karen Devine

Karen Devine

Shelley Harvey

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