The Acute Electrocortical and Blood Pressure Effects of Chocolate

Michelle Montopoli, Larry C Stevens, Constance Smith, George Montopoli, Stephanie Passino, Somer Brown, Lena Camou, Katie Carson, Shannon Maaske, Kathleen Knights, William Gibson, Joyce Wu


Objective: The present study investigated the effects of consuming chocolate on electroencephalograph (EEG) frequencies and localization and on blood pressure.  Method: Across six conditions, 122 participants consumed either higher (60%) cacao chocolate, low (0%) cacao chocolate, higher cacao chocolate +L-theanine, high sugar water, low sugar water, or water.  EEGs, blood pressure, and mood were measured before and after a 60-minute digestion period.  Results: Analyses indicated a decrease in frontal, parietal, and temporal theta and an increase in occipital beta EEG following the consumption of a 60% cacao confection compared with control conditions.  Diastolic blood pressure increased with the consumption of higher cacao chocolate when compared to water alone and to higher cacao chocolate  + L-theanine. Diastolic and systolic blood pressure decreased following consumption of higher cacao + L-theanine chocolate, averaging 4-8 mmHg. No condition-specific mood changes or gender differences were found.  Conclusions: This study suggests an acute stimulating effect of cacao on the human brain and vasoconstrictive effects on peripheral vasculature, the latter of which appear to be offset by an L-theanine additive.  Significance: This is the first known study to investigate acute EEG effects of consuming chocolate and suggests a potential attention-enhancing effect.


Chocolate, Cocoa, Cacao, L-theanine, EEG, Blood Pressure

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