Two recent large scale studies are doubtful about the cardiac benefits of lows-dose aspirin or vitamin supplements.

In the first study, Japanese researchers noted that low-dose aspirin didn’t seem to lower the risk for cardiovascular events in patients with type2 diabetes.

The second study, conducted by Harvard researchers, showed that vitamin E or vitamin C didn’t seem to lower the risk of major cardiovascular events in a middle-aged male physicians’ group.

Diabetics have a much higher risk for cardiovascular events and the American Diabetes Association suggests the use of aspirin as a primary prevention measure. However, researchers from Kumamoto University, Japan say that there is little evidence to support the recommendation.

In the JPAD trial, 2539 Japanese patients with type2 diabetes were randomized. The patients had no history of atherosclerotic disease to low-dose aspirin or included in a non-aspirin control group.

Aspirin showed a slight reduction in the risk of coronary, peripheral vascular and cerebrovascular events in participants.

Some experts say that the study has left many questions unanswered.

According to Dr. Suzanne Steinbaum, director of women and heart disease at Lenox Hill Hospital in New York City, “We need to wait for more studies, and we don’t even know whether we can use this data to extrapolate to an American population.”