Fifty years ago, two Danish epidemiologists pondered why Greenland's native Inuit had a very low rate of heart attacks despite eating a high-fat diet full of whale and seal meat.
They flew to Greenland and collected blood samples from 130 Inuit. Back in the lab, they found chemicals in the samples that they had never heard of before -- called omega-3 fats.
Today, omega-3 fatty acids have become a multibillion-dollar business. Americans spend $2.6 billion on nutritional supplements and foods fortified with omega-3 fats. But not all of this is money well spent.
Decades of research back up the claim that the types of omega-3’s found in marine animals such as fish and krill, called EPA (eicosapentaenoic acid) and DHA (docosahexaenoic acid), can protect your heart. But many of the foods you find at the supermarket are supplemented instead with alpha-linoleic acid (ALA), the type of omega-3 found in nuts and flax seeds.
Cardiologists believe it does not have the same benefits, because your body does a poor job at converting ALA to EPA.