Eating around 250g of seafood twice a week is healthy. But no so much when it’s consumed in excess, and it may also contain methyl mercury, a neurotoxin.

After analyzing the data of 10,673 adults who took part in the  2007-2010 NHANES study, researchers found a link between seafood consumption and blood mercury levels. As seafood consumption increased, so did average blood mercury levels, from 0.45 micrograms/L among people who did not eat fish to 1.70 micrograms/L among those who ate fish five or more times per month.

High frequency in crab and shrimp consumption  was not associated with increasing blood mercury levels but the increasing frequency of both tuna and salmon consumption was associated with a 14% higher risk and other seafood, 12%.

Throw back the mercury filled fish and opt for their smaller brothers, like sardines for example, that are healthier for you.