If you’re eating sardines out of a can for lunch, you’ll be the healthiest, most unpopular person in the office. When it comes to canned fish – from tuna to salmon to sardines – almost all of the varieties are incredibly good for you.
Calorie wise, you’re best off choosing fish that’s stored in a brine compared to oil, but the difference is relatively insignificant.
As for the mercury content of canned tuna, there’s nothing to worry about – most tuna used for canning are small, and haven’t racked up levels of mercury large enough to affect you.