Scientists discovered that Sushi from the supermarket is healthier compared to what's served up in restaurants, as sushi kept in a grocery store often includes the yellowfin variety that is lower in mercury.

According to the new study, tuna is not all the same when it comes to mercury levels. About 100 supermarket and restaurant tuna samples were tested by scientists from The American Museum of Natural History and Rutgers University. DNA barcoding was used by them to find out species, whereas cold vapor mercury analysis was used to test mercury levels.

Scientists found that yellowfin, which is a smaller, cheaper variety usually found in supermarket sushi contained less mercury as compared to bigeye or bluefin varieties. The website of Buffy Martin Tarbox, GotMercury. org, already supports that finding.

According to Buffy stores and restaurants should label species they are serving, as most of the consumers don't know the difference.

Tarbox said, “As the study indicates, different types of species contain higher levels of mercury. Got Mercury believes consumers have a right to know what they are eating and how much mercury is in every piece of fish they are buying”.