Tuna contains lots of mercury, especially blackfin and bluefin tuna. Additionally, there’s precious little free-grown tuna in the stores because it’s nearly extinct. All the fish comes from farms where it’s fed with antibiotics and hormones.
There aren’t many healthy fatty acids in tilapia, yet the concentrations of harmful fats in it are almost as high as in lard. Excess consumption of this fish leads to an increase in cholesterol levels and makes the body more sensitive to allergens.