Diabetes, Nutrition, Obesity and Eating Disorders

Diets high in antioxidant substances (polyphenols) may reduce the risk of cardiovascular events. Low consumption of fruits and vegetables is involved in oxidative stress, hypertension and insulin resistance. Although the consumption of fresh fruit or juice is the best way to acquire its nutritional components, the use of capsules containing fruit extracts has the advantage of being easily consumed and lasting longer. Therefore, studies are needed to support antioxidant supplementation in the form of encapsulated fruit extracts and to verify if the protective properties of these fruits remain after the processing that generates the extracts. Thus, the objectives of this study are: 1) To determine the phenolic content and antioxidant capacity of cranberry, blueberry and pomegranate extracts; 2) Perform evaluation of oxidative stress markers, markers of inflammatory activity, together with hemodynamic assessment. For this, a placebo-controlled clinical trial was conducted with hypertensive and normotensive subjects who received the fruit extract capsules (blueberry, cranberry and pomegranate) for 4 weeks. Hemodynamic, inflammatory mediators, insulin resistance, and plasma antioxidant activity evaluations were performed. Biochemical analysis of fruit extracts showed that the antioxidant activity of phenolic components remains in the capsules. The HOMA-IR index, that discloses insulin resistance, decreased significantly after capsule consumption. Although there were no hemodynamic changes, there was a decrease in lipid peroxidation after capsule consumption and an increase in catalase activity. The results of this study suggest that supplementation with cranberry, blueberry and pomegranate capsules can reverse oxidative damage and reduce insulin resistance in hypertensive patients.