“Your Weekly Checkup” is our online column by Dr. Douglas Zipes, an internationally acclaimed cardiologist, professor, author, inventor, and authority on pacing and electrophysiology. Dr. Zipes is also a contributor to The Saturday Evening Post print magazine. Subscribe to receive thoughtful articles, new fiction, health and wellness advice, and gems from our archive.
Order Dr. Zipes’ new book, Damn the Naysayers: A Doctor’s Memoir.
Dark chocolate in particular has been shown to reduce blood pressure, inflammation, and the amount of bad cholesterol (LDL) in the blood, and improve insulin effectiveness and blood vessel health. Chocolate consumption has also been linked to a decrease in heart failure, diabetes, atrial fibrillation, strokes and heart attacks.
The process of manufacturing dark chocolate retains a chemical compound called epicatechin thought responsible for the major health benefits of chocolate, whereas milk chocolate does not contain significant amounts of epicatechin.
Several studies suggest that dark chocolate from flavanol-rich cacao beans may enhance blood flow to central and peripheral nervous systems, improve cardiovascular function, and retard memory loss and other signs and symptoms of degenerative diseases, including Alzheimer’s and Parkinson’s diseases. The cacao flavanols in dark chocolate have antioxidant effects that retard and partially reverse degenerative changes in various diseases. Dark chocolate consumption also has been associated with enhanced mood and cognition. A recent study of 30 adults tested the impact of dark versus milk chocolate on vision. They noted small enhancements in visual acuity and large-letter contrast sensitivity and a slightly larger improvement in small-letter contrast sensitivity after consumption of dark compared with milk chocolate.
Not all studies on chocolate have been positive. Some negative outcomes might be expected because chocolate contain sugar, caffeine, and calories so that higher amounts of intake might be harmful. That raises the question of whether there might be a dose response association between chocolate intake and cardiovascular outcomes. That is, might there be an optimal protective dose of chocolate that decreases the risk of cardiovascular disease, with lower amounts having no effect and higher amounts causing harm?
A recent study addressed that question by reviewing and compiling information from fourteen reports on over 400,000 participants. The authors found an overall relative risk reduction of total strokes and heart attacks with chocolate intake, the strongest reduction observed between about 45 g/week (a chocolate single or square per day or a chocolate snack bar per week) and 60–75 g/week. The protective effect for cardiovascular disease was lost when chocolate intake exceeded 100 g/week (two chocolate snack bars per week). One needs to accept these results cautiously because chocolate consumption was self-reported, the type of chocolate could not be identified (which may underestimate the protective effects of dark chocolate), and one can only conclude an association between chocolate consumption and cardiovascular disease, not necessarily causality.
So, enjoy your daily dark chocolate wafer that not only tastes good but is good for you.