Grape Consumption Improves Antioxidant Capacity in Humans

16/10/07 A side of grapes with that burger? It is probably a good idea based on health research findings presented at the Second International Symposium on Human Health Effects of Fruits and Vegetables in Houston, Texas this week.

The symposium presented evidence that high antioxidant foods should be consumed with each meal to prevent periods of post-meal oxidative stress. Oxidative stress is linked to aging and the onset of chronic diseases. Antioxidants are known for their ability to neutralize free radicals that are generated by an array of environmental stresses on the body -- from natural processes to external assaults such as smoking and pollution.

Among the fruits specifically highlighted as beneficial were grapes, which, after consumption resulted in almost double the amount of recommended total antioxidant capacity needed to counteract the deficit associated with consuming 1000 calories of food.

Dr. Ronald L. Prior of the USDA's Arkansas Children's Nutrition Center, widely recognized as a pioneer of the ORAC (Oxygen Radical Absorbance Capacity) technique for measuring antioxidant capacity in foods, shared his findings regarding the natural state of oxidative stress in the body that results from eating a meal and the ability to counteract it in humans following consumption of certain fruits.

Prior showed that the metabolic process of digesting a meal with no antioxidants -- just fat, carbohydrate and protein -- causes a decline in antioxidant capacity of the blood which creates a temporary state of oxidative stress. This deficit can be prevented by consuming high antioxidant fruits such as grapes, which in this study provided almost double the amount needed to bring the body back in balance following the meal. His work also showed that some fruits that typically score high in antioxidant content, may not significantly impact oxidative status in the body. The key is "bioavailability," the body's ability to process and use the antioxidants.

"This research reinforced the fact that grapes are a great source of beneficial antioxidants that are bioavailable and able to improve antioxidant status in humans," said Kathleen Nave, president of the California Table Grape Commission. "Based on this research, one easy, proactive step that people can take to help safeguard their health is to eat high antioxidant fruit -- like grapes -- with their meals."

The International Symposium on Human Health Effects of Fruit and Vegetables is a scientific forum in which approximately 300 scientists, nutrition and medical professionals, industry representatives, commodity groups, and legislators from 38 countries gather to exchange information on the latest advances in science relating to the health-maintaining properties of fruits and vegetables. The goal of the conference is to facilitate discussion between the agricultural, nutrition and health sciences, and to advance the science related to foods for health. The conference is hosted by the Vegetable and Fruit Improvement Center of the Texas A&M Agriculture in Houston, Texas.