New evidence

30 days of cocoa flavanols shrank a key heart chamber by 12.6% in healthy older adults—but other markers of heart function didn't budge.

This is the first rigorous trial to link cocoa flavanols to a measurable reversal of early diastolic dysfunction, but with only one study so far, the effect needs replication before it becomes actionable.

Healthy older adults who took 500 mg of cocoa flavanols twice daily for 30 days saw a 12.6% reduction in maximal left atrial volume, a sign that early stiffening of the heart's filling phase may be partially reversed. However, other measures of heart muscle performance—including strain and contraction—showed no improvement, suggesting the benefit is specific to the relaxation phase rather than overall heart function. Because the study was small, short, and the first of its kind, the results invite cautious follow-up rather than immediate supplement recommendations.

Where this fits in the evidence

This is among the first studies we've indexed on Cocoa for Reduced Left Atrial Maximal Volume — treat it as an early signal until more research accumulates.

The study

Cocoa flavanols alleviate early diastolic dysfunction by decreasing left atrial volume in a randomized double blinded trial in healthy older individuals.

Randomized Controlled Trial (RCT)
2025
Food & function

More on Cocoa More on Reduced Left Atrial Maximal Volume

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