An accidental study over at John Hopkins University shows that a small daily amount of dark chocolate can thin out blood and slow down the time it takes for blood clots to form, which is similar to the effect of aspirin.

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The research included 120+ people, which was based off the effects of aspirin(focusing on reducing blood platelet clogging, which can decrease the chance of heart attack). They were asked to not consume chocolate and were subjected to other restrictions as to not throw off the study, but some of these subjects couldn't stick to the rules.

Regardless of their chocolate weakness, the subjects were compared to the ones who followed the rules. The ones who ate chocolate during the test had an average of 130 seconds for the platelets to clot, while the others took 123 seconds. With this effect, it can reduce the chance of heart attacks up to 50%.

This is just another plus for dark chocolate, which also benefits for having antioxidants and the ability of improved blood flow.

Source: chocolate aspirin