From personal experience I can tell you that being pregnant or nursing a baby makes daily eating complicated. During my pregnancy, I made an effort to avoid potential "high risk" foods such as artificial sweeteners, caffeine, and alcohol. In addition, I tried to eat calcium-fortified foods, at least five servings a day of fruits and vegetables, and a balanced diet overall. However, one food for which I had trouble deciphering the good and bad press during my pregnancy: fish.

Over the past year this blog has discussed the many health benefits of fish. It's a rich source of protein. It's low in saturated fat and high in omega-3 fatty acids. Experts recommend consuming 2 or 3 servings of fish a week to help reduce the risk of heart disease.

But there are exceptions -- and the exceptions include you, if you are planning to become pregnant, are already pregnant or nursing, or if you're a young child. In these cases, the Food and Drug Administration recommends modifying the type and amount of fish you consume to avoid fish that contain high levels of mercury, such as shark, swordfish, king mackerel, and tilefish. Safe bets are shrimp, salmon, tilapia, pollock, and catfish.

One fish that appears on both the safe and unsafe lists is that staple of the American diet, tuna. Until recently the recommendation was to avoid albacore (white) tuna, but canned light tuna is on the list as safe to eat. Consumer Reports is currently debating whether this recommendation still holds true. In a recent analysis of mercury levels in canned fish, CR showed that 6 percent of the canned light tuna tested contained as much or more mercury than the albacore, which is already on the list of foods to avoid.

Is tuna safe to eat or not? The FDA still claims that canned light tuna is safe to include in your diet regardless of pregnancy or nursing status or age, and maintains that consumption of mercury in the amounts available from this type of tuna would not be high enough to cause concern.