Studies suggest that oxidative stress may play a role in the pathogenesis of insulin resistance and type 2 diabetes
The total antioxidant capacity is an estimate of the antioxidant effect of all dietary components.
Previous studies have reported that higher total antioxidant capacity is associated with lower risks of metabolic syndrome, abdominal obesity and hypertension.
A study published by Mancini, et al. in 2017 is the first prospective study to evaluate the relationship between total antioxidant capacity and the risk of type 2 diabetes.
The French E3N-European Prospective Investigation into Cancer and Nutrition (EPIC) cohort was the source of data for this study.
A total of 64,223 women (mean age = 52 years) in the E3N-EPIC cohort completed baseline food questionnaires, and 1751 developed type 2 diabetes during 15 years of follow-up.
Total antioxidant capacity was calculated by the ferric ion-inducing antioxidant power (FRAP) index, excluding the contribution from coffee.
The FRAP index was categorised by quintile, with the lowest quintile group used as the reference group.
Multivariable analysis found that higher antioxidant capacity was significantly associated with a lower risk of type 2 diabetes.
Compared with women in the lowest quintile, those in the 3rd, 4th, and 5th quintiles had hazard ratios of 0.74, 0.70, and 0.73, respectively.
The inverse relationship between total antioxidant capacity and risk of type 2 diabetes was linear up to FRAP values of 15 mmol per day, after which the effect plateaued.
When coffee was included in the FRAP calculation, the inverse association between antioxidant capacity and type 2 diabetes was still present but weaker, and the effect disappeared in those with the highest coffee consumption.
The food groups that contributed most to the total antioxidant capacity in this study were fruits (23%), vegetables (19%), alcoholic beverages (15%), and hot beverages such as tea, chicory, and hot chocolate (12%).
Greater consumption of these antioxidant-rich foods may play a role in reducing the risk of type 2 diabetes in middle-aged women.