Pregnancy Diet

Among the most popular -- and for some, the most daunting -- of all pregnancy myths are those related to daily diet. While it's vital to maintain a healthy diet, that's not always easy, particularly when we're unsure of exactly which foods we can and cannot have.

The good news: Whatever foods are healthy for mom are healthy for baby, says Peter Bernstein, MD, an obstetrician at Montefiore Medical Center in New York City.

"Virtually all fruits and vegetables, whole grains, some diary, and most protein sources are good choices for mom and good choices for baby. There are really very few foods you need to avoid," says Bernstein.

Fish is among the foods that cause concern because of mercury, a metal that can be toxic to babies, children, and even adults.

The FDA suggests pregnant women not eat more than 12 ounces (two average-size servings) of fish per week. Allowable fish include canned light tuna, shrimp, salmon, pollack, or catfish. For albacore tuna (also known as "white" tuna), which has higher mercury content than canned light tuna, consumption should be limited to 6 ounces per week.

Fish to avoid include swordfish, shark, king mackerel, and tilefish, which contain high levels of mercury.

A report in the journal Science showed that that when compared to wild salmon, farmed salmon contained significantly higher levels of contaminants linked to birth defects and developmental problems, including PCBs.

Though the report set off a panic alarm for many pregnant women, the PCB levels found in the farmed salmon were still lower than levels the FDA considers acceptable. The American College of Obstetricians and Gynecologists recommends following the FDA guidelines.

"The bottom line is that there does not appear to be enough evidence to suggest that there is any more risk to eating farmed compared to wild salmon. And the benefits to eating at least some fish on a regular basis probably outweigh any risk," says Bernstein.

Also, a large study published in the British medical journal Lancet in February 2007 showed that fish is an important food to include in the pregnancy diet.

After looking at nearly 12,000 children, researchers found those whose mothers ate the most fish during pregnancy had a "higher intelligence quotient" than those whose mothers abstained from fish. The children of the fish-eating moms also appeared to have better motor and communication skills as well as social skills.

The key component of fish is omega-3 fatty acids, which Bernstein says are critical to fetal neural development.

And although fish contains high levels of omega-3 fatty acids, there are other good sources, including flaxseed, nuts (particularly walnuts), soybeans, and eggs. There are also many foods fortified with omega-3s, including breads, juices, margarines, and oils, as well as omega-3 supplements. However, be aware that many of the sources of this omega-3 are from fish oil.

Other foods you should try to avoid during pregnancy, says Bernstein, include those with a link to listeria, a bacterium that may increase the risk of miscarriage, premature birth, stillbirth, or fetal illness.

According to the FDA, foods more likely to contain listeria include:

• Unpasteurized milk and soft cheeses such as feta, Brie, Camembert, Roquefort, queso blanco, and Panela, unless the label says "made with pasteurized milk"
• Refrigerated meat spreads or pates
• Refrigerated smoked seafood (unless it is cooked in a casserole or other dish)
• Hot dogs and deli meats, unless they are heated until steaming

Experts also warn against eating undercooked eggs, raw eggs, or eggnog made with uncooked eggs, which can be contaminated with salmonella. "Problems can ensue due to vomiting and dehydration that can occur if you contract salmonella during pregnancy," says Bernstein.