Effect of Cocoa Supplementation on the Biochemical and Clinical Profile and the Somatosensory Processing of Diabetic Peripheral and Autonomic Neuropathy: A Randomized Clinical Trial

Peripheral and autonomic neuropathy are common in type 2 diabetes; they are associated with oxidative stress and inflammation. Cocoa, rich in polyphenols, may offer neuroprotective benefits. This study evaluated the effect of cocoa supplementation on the biochemical, clinical, and somatosensory profile of neuropathy in individuals with type 2 diabetes. A 12-week, double-blind controlled trial involved 39 subjects randomized to receive cocoa capsules (50 mg polyphenols) or placebo (methylcellulose). Evaluations included glycemic and lipid profiles, neutrophil/lymphocyte ratio, blood pressure, standardized questionnaires, anthropometric measurements, and the rate-dependent depression of the H-reflex. In the cocoa group, the Toronto score decreased by 2.63 points and the BEST score decreased by 1.45 points. In the placebo group, these reductions were 1.84 and 2.21 points, respectively. Neither difference was statistically significant between groups (p > 0.05). Quality-of-Life questionnaire score decreased by 9.2 points in the cocoa group, but without significant difference to the placebo group (p = 0.501). Fasting glucose and HbA1c levels decreased in the placebo group by 38 mg/dL (0.28%) but were not significantly different from the cocoa group (p > 0.05). No other intra- or inter-group differences were significant (p > 0.05). Cocoa supplementation did not show significant improvements over the placebo in the measured outcomes. Both groups showed persistent abnormalities in spinal somatosensory processing, with an RDD of the H-reflex ≥ 0.5.