BACKGROUND: Sleep deprivation is a risk factor for cardiovascular disease. Cocoa 
flavonoids exert cardiovascular benefits and neuroprotection. Whether chocolate 
consumption may mitigate detrimental effects of sleep loss on cognitive 
performance and cardiovascular parameters has never been studied.
AIM: We investigated the effects of flavanol-rich chocolate consumption on 
cognitive skills and cardiovascular parameters after sleep deprivation.
METHODS: Thirty-two healthy participants underwent two baseline sessions after 
one night of undisturbed sleep and two experimental sessions after one night of 
total sleep deprivation. Two hours before each testing session, participants 
were randomly assigned to consume high or poor flavanol chocolate bars. During 
the tests were evaluated, the Psychomotor Vigilance Task and a working memory 
task, office SBP and DBP, flow-mediated dilation and pulse-wave velocity.
RESULTS: Sleep deprivation increased SBP/DBP. SBP/DBP and pulse pressure were 
lower after flavanol-rich treatment respect to flavanol-poor treatment (SBP: 
116.9 ± 1.6 vs. 120.8 ± 1.9 mmHg, respectively, P = 0.00005; DBP: 70.5 ± 1.2 vs. 
72.3 ± 1.2 mmHg, respectively, P = 0.01; pulse pressure: 46.4 ± 1.3 vs. 
48.4 ± 1.5 mmHg, P = 0.004). Sleep deprivation impaired flow-mediated dilation 
(5.5 ± 0.5 vs. 6.5 ± 0.6%, P = 0.02), flavanol-rich, but not flavanol-poor 
chocolate counteracted this alteration (flavanol-rich/flavanol-poor chocolate: 
7.0 ± 0.6 vs. 5.0 ± 0.4%, P = 0.000001). Flavanol-rich chocolate mitigated the 
pulse-wave velocity increase (P = 0.001). Flavanol-rich chocolate preserved 
working memory accuracy in women after sleep deprivation. Flow-mediated dilation 
correlated with working memory performance accuracy in the sleep condition 
(P = 0.04).
CONCLUSION: Flavanol-rich chocolate counteracted vascular impairment after sleep 
deprivation and restored working memory performance. Improvement in cognitive 
performance could be because of the effects of cocoa flavonoids on blood 
pressure and peripheral and central blood flow.