Tuna is one of the most convenient protein sources that exists, so it can easily become a guy’s go-to lunch. But is it safe to eat it every day?

The short answer: Probably. But if you’re wrong, you could end up with mercury poisoning, which can cause weird symptoms like tingling sensations and loss of balance, says Michael Gochfeld, M.D., Ph.D., a researcher with the Environmental and Occupational Health Sciences Institute.

“It would likely be safe for many men to eat tuna every day, while some men could experience symptoms of mercury toxicity from eating the same amount,” says Food and Drug Administration spokeswoman Lauren Sucher.

Here’s why it’s so complicated: You have to balance the benefits of eating fish with the risk from mercury, while taking into account a person’s weight, their sensitivity to mercury, the type of tuna, and how much risk you’re willing to take, says Dr. Gochfeld.

Nearly all seafood contains traces of mercury, according to the FDA. So the question is: At what level does mercury become poisonous?

That’s where it gets even more confusing. No one knows exactly where mercury goes from being harmless to toxic, because you’d have to poison people to find out, says Men’s Health nutrition advisor Alan Aragon, M.S.

Most experts can agree on at least two facts, though.

#1: Fish is good for you. Research has shown that it may lower your risk of heart disease, stroke, obesity, cognitive decline, depression, cancer, inflammatory disorders, and asthma, says Dariush Mozaffarian, M.D., Dr.P.H., dean of the Friedman School of Nutrition Science and Policy at Tufts University. Restricting your fish intake could make you miss out on all those benefits.

#2: The risks from mercury have been overhyped. Mercury can harm the developing nervous systems of fetuses and young children, according to the FDA. But when the agency warned pregnant women to limit consumption of high-mercury fish in 2004, it set off unnecessary panic for everyone else, Dr. Mozaffarian says.

The truth is, those warnings never applied to the general public. However, it is possible for adults to get mercury poisoning. You just have to eat a lot of high-mercury fish for that to happen.

Our advice: Almost all guys will be perfectly fine eating a can of light tuna four times a week.  Other types of tuna such as tuna steak have higher amounts of mercury so take that in to account when figuring out your tuna intake.