If you take coated aspirin, are you getting the same heart-protective effects you would from uncoated aspirin?

You may not be, according to University of Pennsylvania researchers, who were examining the drug to test whether some people are resistant to its effect of heart attack and stroke prevention. They concluded that it wasn't the drug itself but its coating to buffer the stomach from upset that interfered with the heart-protective effects, the New York Times reports. What's more, they found scant evidence that coated aspirin protected the stomach more than uncoated aspirin.

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The study, which was published Tuesday in the journal Circulation, was testing the claim that between 5 percent and 40 percent of the general population is "aspirin-resistant," and that this leads to the prescribing of more expensive drugs to achieve the same effect of inexpensive aspirin, which is sold over-the-counter.

To read the complete New York Times story go here.