The COSMOS-Web trial

COSMOS-Web aimed to investigate at scale whether flavanol intake is related to memory and cognitive aging.

COSMOS-Web trial snapshot

• It is an independent trial undertaken under the umbrella of the COcoa Supplement and Multivitamin Outcomes Study (COSMOS)
• Randomized, double-blind, placebo-controlled
• Involved over 3,500 healthy men and women in the US aged 60 or older for three years, who were enrolled in the COSMOS parent trial
• Initiated by investigators at Columbia University

Published in Proceedings of the National Academy of Sciences entitled, Dietary flavanols restore hippocampal-dependent memory in older adults with lower diet quality and lower habitual flavanol consumption, COSMOS-Web demonstrated a beneficial effect from daily cocoa flavanol supplementation on memory and cognitive performance. It is the largest and longest trial looking at the role of diet and flavanol consumption on normal cognitive aging.

Results showed:

• That flavanols work to maintain memory and cognitive performance during normal cognitive aging.
• At the start of the trial, those with higher dietary flavanol intake already performed better in memory tasks that were designed to probe the hippocampus, a brain region that is sensitive to age-related memory decline. This was before participants had taken any cocoa flavanol supplementation.

Cocoa flavanol supplementation did not improve memory in all participants, but mainly in those with lower flavanol intake at the start of the study.

• Following one year of flavanol supplementation, participants in the group representing lower dietary flavanol consumption improved flavanol intake by 24% and memory performance by 16%, and now matched the memory performance of those with a relatively higher flavanol intake at the beginning of the trial.
• This improvement in memory performance appeared to be sustained over three years of follow up.

Additional information:

Published paper: Dietary flavanols restore hippocampal-dependent memory in older adults with lower diet quality and lower habitual flavanol consumption

Clinical Trial Registry: Investigating the Effects of Cocoa Flavanol on Cognition Assessed Online (COSMOS-Web)