Acute Effects of Cocoa Flavanols on Blood Pressure and Peripheral Vascular Reactivity in Type 2 Diabetes Mellitus and Essential Hypertension

Abstract

Background: Type 2 diabetes mellitus (T2DM) is associated with a high risk of vascular complications. Interestingly, cocoa flavanols (CF) can exert beneficial vascular effects in non-diabetic subjects. However, these effects have only been scarcely studied in T2DM. Therefore, we performed a study to assess the effects on vascular reactivity of a single dose of CF (790 mg) in T2DM and whether certain antihypertensive drugs may modulate these effects. Methods: 24 non-diabetic and 11 T2DM subjects were studied in a cross-over design. Fasting blood samples, blood pressure (BP), and arterial vasoreactivity (flow-mediated dilation) were assessed before and 70 min after capsule ingestion. Muscle microvascular reactivity was only assessed after capsule ingestion. Age, waist-to-hip ratio, BP at baseline, and the use of antihypertensive drugs were regarded as covariates in a mixed models analysis. Results: CF ingestion did not affect any parameter. However, independent of the type of capsules ingested, a decrease in diastolic BP by 3 mmHg (95% CI: −4.0; −2.0) and an increase in the change in brachial artery diameter (pre vs. post occlusion) by 0.06 mm (95% CI: 0.01; 0.12) were detected in the non-diabetic group, while they remained unchanged in the T2DM group. Conclusion: No beneficial effects of CF were detected on vascular reactivity parameters in T2DM and non-diabetic participants.

From Cocoa to Chocolate: Effect of Processing on Flavanols and Methylxanthines and Their Mechanisms of Action

“…Moreover, 200 mg daily of monomeric and oligomeric flavanols for three months on top of habitual diet and usual care did not reduce the plasma markers of endothelial dysfunction compared to the placebo in patients with long-term type 2 diabetes [197]. Finally, early this year, a crossover trial with type 2 diabetic (T2DM) and non-diabetic subjects that received 790 mg of cocoa flavanols daily reported that no beneficial effects of cocoa flavanols were detected on the vascular reactivity parameters in T2DM and non-diabetic participants [190].…”

“…Last year, a meta-analysis restricted to diabetic patients suggested that there is weak evidence for a reduction in diastolic but not systolic blood pressure after mid/long-term cocoa flavanol administration. These effects seem stronger in females, younger, and hypertensive when cocoa flavanols are ingested in one daily intake and when the epicatechin content is high enough [190].…”