Can you eat too much tinned tuna?

Nazar Rybak/Getty Images Tinned tuna is a lunchbox staple for many people. It’s affordable, high in protein and doesn’t need cooking, making it a nutritious and convenient option for busy days. But if you’re eating tuna most days, you might have wondered whether it’s possible to have too much. Or perhaps you’ve watched your child happily eat a tuna sandwich every day for a week and wondered if that’s too much of a good thing. The concern usually comes down to mercury. Mercury can be harmful in…