In a nutshell
This study evaluated the potential benefit of grape polyphenols in protecting the body against the damages of oxidative stress and insulin resistance.
Some background
The typical Western diet, especially one containing high amounts of processed foods, is generally rich in the sugar fructose. A fructose rich diet results in overconsumption of calories, high blood sugar levels, damage to cells (through a process called oxidative stress) and insulin resistance (failure of cells to respond to the normal actions of insulin). Both oxidative stress and insulin resistance significantly increase the risk of common diabetic complications such as cardiovascular disease.
The relatively low incidence of cardiovascular disease in France, despite a diet high in saturated fats, has stimulated interest in the potential health benefits of grape polyphenols. These natural chemicals found in grapes are known to act as anti-oxidants. It has been suggested that the addition of grape polyphenols to processed foods could aid in the prevention of metabolic diseases such as diabetes and their complications. This study assessed the efficiency of supplemental grape polyphenols in offsetting the effects of a fructose rich diet among individuals at a high risk for developing metabolic disease.
Methods & findings
38 overweight or obese individuals, all first degree relatives of type II diabetic patients, were included in this study. Participants were randomized to receive either a grape polyphenol supplement or a placebo for 9 weeks. During the last 6 days of the study, patients in both groups received high amounts of fructose. The effects of fructose were assessed through measurements of insulin sensitivity and oxidative stress.
In the placebo group, high fructose consumption led to a 20% reduction in insulin sensitivity. A significant increase in oxidative stress byproducts was also encountered. In comparison, these negative effects of high fructose dosing were fully counteracted among patients receiving grape polyphenol supplementation.
The bottom line
This study concluded that grape polyphenols protect against oxidative stress and insulin resistance with no noted adverse effects.
The fine print
This study included only a very small sample of patients. A larger study should be conducted to confirm these results.
What’s next?
Consult with your physician regarding the potential benefit of an anti-oxidant rich diet in preventing diabetic complications.
Published By :
Diabetes Care
Date :
Jun 01, 2013
