Cocoa Extract Supplementation and Risk of Type 2 Diabetes: The Cocoa Supplement and Multivitamin Outcomes Study...

Area of Science:

• Nutritional Science
• Clinical Trials
• Diabetes Prevention

Background:

• Observational studies suggested cocoa flavanol supplements may aid type 2 diabetes (T2D) prevention.
• A large randomized clinical trial (RCT) was needed to confirm clinical efficacy.

Purpose of the Study:

• To evaluate the clinical efficacy of cocoa extract supplementation for preventing incident type 2 diabetes (T2D) in middle-aged and older adults.
• To assess the effect of daily cocoa flavanol intake on T2D development in a large-scale RCT.

Main Methods:

• The Cocoa Supplement and Multivitamin Outcomes Study (COMSOS) was a 2x2 factorial RCT.
• 18,381 participants without diabetes were randomized to receive 500 mg/day cocoa extract (80 mg (-)-epicatechin) or placebo.
• Incident T2D was assessed over a median follow-up of 3.5 years using intention-to-treat analyses.

Main Results:

• No significant reduction in incident type 2 diabetes (T2D) was observed in the cocoa extract group compared to placebo (HR 1.04, P=0.58).
• Cocoa extract supplementation did not significantly alter T2D risk across various subgroups including sex, race, BMI, and lifestyle factors.
• The median follow-up was 3.5 years, with 801 incident T2D cases reported.

Conclusions:

• Cocoa extract supplementation for 3.5 years did not reduce the risk of developing type 2 diabetes in middle-aged and older adults.
• Further research is warranted to explore cocoa extract's effects earlier in adulthood and in diverse populations.
• The study did not support cocoa flavanols as a strategy for T2D prevention in this demographic.