Archived Research:
On oxidative stress and antioxidants in diabetes

Researchers have found that oxidative damage plays a role in the damage to tissues caused by diabetes. Our cells utilize oxygen in the making of energy, but that process produces free radicals, toxic byproducts that damage our DNA and proteins. Our bodies produce natural antioxidants to sop up those free radicals and reduce the amount of damage they can do. We get other antioxidants in our diets.

Oxidative damage increases with aging as well. Italian researchers at Perugia University Hospital looked at older diabetics (average age 75 years) to examine the effects of oxidative damage from two sources, aging and diabetes. The scientists measured blood levels of several antioxidants (vitamin A, vitamin E, and a group known as carotenoids) in 72 people with diabetes and 75 without. All of the antioxidant blood levels were significantly lower in the diabetic patients, and the lowest levels were found among the very oldest in the study.

Japanese scientists have demonstrated that oxidative stress damages the insulin-producing cells of the pancreas in rats, which can worsen diabetes. Their studies suggest that antioxidant supplements in animals may reduce that damage. They refined their experiments by administering vitamin E to diabetic rats in doses of 0, 20, and 500 milligrams. The rats fed the highest dose of vitamin E showed a significant increase in insulin levels and a significant decrease in sugar levels. They also had better blood sugar control. The implications of these and related studies, of course, must be explored further in humans.

The role of oxidative damage and possible role of antioxidants is under very active study in both diabetes and in aging. While there are many animal studies in these areas, convincing studies in humans are still limited. Because overuse of antioxidants can be damaging, the use of antioxidant supplements needs to be considered carefully and along accepted, research-confirmed guidelines.