Earlier this year in June, for the first time, the Environmental Protection Agency and Food and Drug Administration proposed a weekly minimum for eating fish. However, they now have a new view on this matter. 

Fish is great for you. It is high in Omega-3 fatty acids but it can also contain levels of mercury which could be dangerous. So here are the new guideline that have come out. “We’re particularly concerned about canned tuna, which is second only to shrimp as the most commonly eaten seafood in the United States. We encourage pregnant women to avoid all tuna.”“Though we urged CR to do a thorough, balanced and science-based job, that obviously did not happen. Minimal research would have presented reporters literally hundreds of independent seafood studies from the FDA to the World Health Organization that clearly demonstrate the net benefit gained from eating seafood, like tuna.”

We know that avoiding all fish can also not be good, which is why they are specifically calling out tuna as it has high levels of mercury and include in the report that the FDA "may be underestimating the danger."