Reactive oxygen species are a normal part of life, however, problems begin to arise when our body is not capable of defending against them.  Under healthy situations  reactive oxygen species or free radicals can be neutralized through antioxidant enzyme systems in our body or through dietary polyphenols.

One way to determine if our body can defend against free radicals is to test the ‘redox potential’ of urine.  This test can be used to determine your antioxidant status.  Under normal conditions higher levels of ‘redox potential’ suggest lower antioxidant status, while lower levels of ‘redox potential’ suggest better antioxidant potential.  In short, the body is better equipped to defend against free radical damage when the redox potential is lower.

A recent clinical trial published in Nutrition Journal tested if a grape seed extract could decrease the redox potential in healthy human volunteers.  There has been a lot of interest in grape seed extract by scientists with more than 900 articles published in scientific journals with many health promoting properties.  One in particular is the ability of grape seed extract to improve antioxidant status.

In this clinical trial 46 human subjects (20 males and 26 females) participated in the study.  On day 1 of the study the participants consumed biscuits without grape seed extract and then had their antioxidant status evaluated.  On day 2 of the study the participants were given biscuits with a total of 2,000 milligrams of grape seed extract and then had their antioxidant status evaluated.  The amount of grape seed extract is equivalent to about  4 capsules of a dietary supplement.

Here is what grape seed extract was found to do after 12 hours and the conclusion of the authors:

• The redox potential was reduced by 33% compared to patients not consuming grape seed extract.
• The interpretation of this data by the authors is that the ‘antioxidant status’ was improved
• The most important result from this study was that after just one day antioxidant status was significantly improved.

The long term implications of this study are unknown as this tested a single dose.  However, it is well established that reactive oxygen species are involved at the very earliest stages of disease initiation.    When reactive oxygen species are left unchecked they will cause damage to cell membranes, DNA, and proteins in our bodies.  If someone’s antioxidant status is low for long periods of time the damage caused by free radicals will begin much sooner and begin to comound rather than someone who has a higher antioxidant status on a regular basis.

Take away message:   After just one day of taking grape seed extract, 1,000 mg in the morning and 1,000 mg in the evening, antioxidant status of healthy volunteers was significantly improved.  Many scientists and clinicians have suggested that a lower antioxidant status over long periods of time can help promote chronic disease such as inflammation, arthritis, cancer, heart disease, Alzheimer’s disease as well as others.  Grape seed extract may be one component along with other lifestyle choices to help improve antioxidant status that will help defend against free radical damage.

Nutrition Journal.  2015 September 9; Volume 14: Page 94-101.

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Jeremy Johnson, PharmD, PhD

Dr. Johnson is a tenured associate Professor and licensed Pharmacist at the University of Illinois at Chicago College of Pharmacy.

His research on plant medicine has led to more than 45 publications and abstracts.This research has been presented at international meetings in the USA, France, Turkey, Peru, Israel, Austria, and Italy.

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Categories: Antioxidant, Clinical Trials, Plant Extracts