Overview
- University of Birmingham researchers reported that men who consumed a cocoa beverage with 695 mg of flavanols avoided the drop in flow‑mediated dilation typically seen after two hours of uninterrupted sitting.
- Participants given a low‑flavanol drink (5.6 mg) showed declines in FMD in arm and leg arteries, higher diastolic blood pressure, reduced blood flow, and lower leg muscle oxygenation.
- The trial enrolled 40 healthy men split by cardiorespiratory fitness, and the protective effect of flavanols was consistent in both higher‑fit and lower‑fit groups.
- Authors propose that flavanols enhance nitric oxide availability via endothelial nitric oxide synthase to support vasodilation, a mechanistic explanation they note is still being refined.
- Findings were published October 29 in The Journal of Physiology (DOI: 10.1113/JP289038); the male‑only, short‑term study used a high dose and the researchers plan follow‑up work, as even a 1% FMD drop has been linked to a 13% higher cardiovascular risk.