Sushi. It’s a tasty, low-fat meal many people enjoy. And a growing number of Americans are bellying up to the sushi bar on a regular basis.

Fish is generally healthy and even government-recommended as a source of protein. But many are starting to wonder just how dangerous fish… especially in the form of sushi… really is.

Raw fish can contain high levels of chemicals as well as put you at risk for bacterial illnesses. And sushi made headlines recently after The New York Times commissioned lab tests that detected so much mercury in tuna sold in several Manhattan restaurants that eating just six pieces a week would exceed E-P-A standards.

Mercury gets into oceans and lakes, where it converts into methylmercury, which builds up in fish. It can damage the developing nervous system and cause hair loss and vision problems in adults. Still, while pregnant and nursing women, young children, older people and those with weak immune systems should avoid raw fish, this doesn’t mean everyone must.

According to the F-D-A, eating sushi shouldn’t be reason to panic. One week’s consumption doesn’t change the level of methylmercury in your body by much, and expert advises compensating by cutting back the next week. Wild salmon, farmed oysters and herring are fish known to be lower in contaminants, while shark, swordfish, king mackerel and tilefish are the worst offenders. So know your fish and be reasonable about the amount you consume… and mealtime should go just swimmingly.