Antioxidant Vitamins and the Metabolic Syndrome

By: Robert M. Blair, Ph.D.

Antioxidants are well known for their multitude of health benefits. While there are a wide variety of antioxidants, the best-known antioxidants are vitamins A, C and E. A recent study investigated the impact of the antioxidant vitamins A and E on the metabolic syndrome, a cluster of risk factors for cardiovascular disease and diabetes.

For this study, data on vitamin supplement use was pulled from the 2010 – 2011 Korea National Health and Nutrition Examination Survey. From this data, it was determined that 1,847 adults were supplement users, while 4,461 adults were not supplement users. The prevalence of the metabolic syndrome in these two populations as analyzed and compared in relation to their dietary intake data and a database of common Korean foods which included the antioxidant contents of those foods.

When comparing dietary intake of antioxidants, not including dietary supplements, supplement users and supplement non-users had a similar antioxidant intake with the exception of vitamins A and E, which were higher in the supplement users’ diet. As one would expect, when including the intake of dietary supplements, the intake of vitamin A, retinol, vitamin C, vitamin E, and total antioxidant capacity was higher in the group that used a dietary supplement. Intake of vitamins C and E were the greatest contributors to total antioxidant capacity

Furthermore, when comparing the relationship between antioxidant intake and the metabolic syndrome, it was found that the prevalence of the metabolic syndrome was significantly lower in the dietary supplement users than in the non-supplement users. Among just dietary supplement users, the data showed that those in the highest third of vitamin A intake and those in the highest third of vitamin E intake had a lower risk for the metabolic syndrome compared to dietary supplement users in the lowest third of vitamin C and vitamin E intake. Similarly, those in the highest third of total antioxidant capacity had a lower risk for the metabolic syndrome compared to dietary supplement users in the lowest third for total antioxidant capacity. The highest third of vitamin E intake was also shown to be associated with a lower level of abdominal obesity.

Overall, these data suggest that getting adequate levels of vitamins A and E as well as an overall good level of total antioxidants can help lower one’s risk for the metabolic syndrome.