The health benefits of fish are ever growing. In a recent study of children 6 months to 8 years old, researchers in Great Britain found that pregnant women who ate at least two servings (12 ounces) of fish per week were 52 percent less likely to have a child with low verbal IQ scores. And a Finnish study found that eating fish during pregnancy can reduce a woman's risk of preterm delivery. Many fish are high in healthy fats called omega-3s, which may account, at least in part, for these benefits.
The U.S. Food and Drug Administration and the U.S. Environmental Protection Agency say you can safely eat up to 12 ounces of low-mercury fish a week. Some low-mercury fish that are also rich in omega-3s are salmon, herring, anchovies, caviar, and sardines.
Although many fish are healthy, several can be dangerous to eat. These contain trace amounts of mercury; the metal accumulates in a fish's tissue and is most concentrated in swimmers at the top of the food chain, like sharks, that eat other, smaller fish. For this reason, the FDA and EPA advise pregnant women not to eat swordfish, shark, king mackerel, and tilefish. These may contain enough mercury to harm an unborn baby's developing nervous system -- mercury bypasses the placenta and goes straight to a baby's brain.
The FDA also advises limiting the amount of canned albacore tuna you eat to 6 ounces or less a week. Its mercury content is on average three times that of canned chunk light tuna. Also on the no-go list: game fish such as trout and bass, because they can be contaminated with mercury or other industrial pollutants.
Raw fish, especially shellfish, are potentially dangerous because they can contain harmful microbes that can lead to severe gastrointestinal illness. Smoked seafood like lox is also a no-no unless it's part of a fully cooked dish.
Whatever you're serving, make sure it's thoroughly cooked -- check that the fish is opaque and flakes easily with a fork.
Vegetables and Juice
Raw vegetable sprouts are loaded with vitamins. But they often carry disease-causing bacteria such as salmonella and E. coli; seeds may become contaminated by animal manure, and hot and humid growing conditions allow bacteria to flourish. Sprouts -- including alfalfa, radish, and mung bean (Chinese sprouts) -- are often added to sandwiches and salads, so request that yours are prepared without.
Also, drink only pasteurized juice (packaged unpasteurized juice is identified on the label). Most of the time you don't need to worry about this: 98 percent of fruit and vegetable juices sold in supermarkets are pasteurized. But it becomes a bigger issue at restaurants, juice bars, and farm stands, where unpasteurized juices are commonly served.
In healthy adults, salmonella and E. coli infections cause diarrhea, nausea, abdominal cramping, and fever that last for several days. Pregnant women, however, can become seriously ill from these infections and can occasionally pass the infection to their fetus.
Deli Meats and Cheese
Some soft cheese, unpasteurized milk, and ready-to-eat meat (including deli meats, packaged lunch meats, and hot dogs) contain listeria, a bacteria that can cause a type of food poisoning called listeriosis. This infection is especially dangerous during pregnancy and can cause miscarriage or stillbirth. Although you should avoid unpasteurized soft cheese, there is a way to get your fill of deli meat and hot dogs: heat until steaming hot -- this should kill any bacteria.
Most people don't get sick when eating listeria-contaminated food. But, for reasons not thoroughly understood, pregnant women are about 20 times more likely than other adults to get listeriosis and become very ill from it. The infection often starts with flu-like symptoms, and prompt treatment with antibiotics can prevent serious side effects.
Meat and Eggs
Lean meats, poultry, and eggs are good choices for a healthy pregnancy because they're rich in protein and vitamins. But make sure they're thoroughly cooked. Raw or undercooked versions can increase your risk of a number of food-borne illnesses, including listeriosis, E. coli and salmonella infections, and toxoplasmosis.
Toxoplasmosis is an illness that often causes only mild flu-like symptoms or none at all. But if a pregnant woman contracts it, her baby may develop birth defects such as vision loss and mental retardation. If it's caught early enough, though, it can be treated with antibiotics.
Use a meat thermometer to make sure meat and poultry are thoroughly cooked. Pork roasts and chops and ground beef should be cooked to at least 160 degrees F., when no pink is visible; beef, veal, and lamb roasts and steaks to 145 degrees F., where the meat is slightly pink in the center; whole poultry to 180 degrees F.; and chicken breasts to 170 degrees F. Cook eggs to the point where both yolk and white are firm, and avoid foods made with raw or partially cooked eggs, like egg nog and hollandaise sauce.
Most foods that make up a healthy diet are safe for you and your baby. But for now, see you later, trout and alfalfa sprouts, and bring on the salmon, veggie sushi, and pasteurized feta!
Canned chunk light tuna
Canned albacore tuna
Vegetable or cooked-fish sushi
Cooked sprouts and mung beans
Pasteurized feta and goat's milk cheese
Laughing Cow cheese
Steaming hot deli meat, packaged lunch meat, and hot dogs
Well-cooked meat and eggs
Food to Avoid
Unpasteurized feta and goat's milk cheese
Refrigerated or room-temperature deli meat
Packaged lunch meat and hot dogs
Undercooked meat and egg
How Real Moms Dealt with Pregnancy Cravings
"I'm 36 weeks pregnant, and I find comfort in PB&J. Lunch meats are off-limits most times, so it's an easy fix if you're craving a sandwich."
--Katie Neitz, Emmaus, Pennsylvania
"I craved more of things I already liked. We still went out for sushi, and I just had cooked items -- usually shrimp tempura and a California roll."
--Sarah Buck, Tallahassee, Florida
"I'm a fancy-cheese fanatic. Throughout both of my pregnancies, I had to be especially careful when eating out if I didn't know whether or not a cheese was made with pasteurized milk. A few times, the waiter actually brought out the cheese in its package for me so I could read the label."
--Kristin Ruethling Dufek, Fox Point, Wisconsin
"I craved Brie, which is a no-no. I substituted the soft Laughing Cow cheese and still snack on it today. It's much better for you too."
--Caryn Pollock, Staten Island, New York
"For my husband's birthday, our friends decided to go for a steak dinner. Everyone ordered rare meat -- which is unsafe and made my stomach turn. I ordered spaghetti. It was quite a sight to see all the meat at the table next to my massive plate of plain and simple spaghetti!"
--Ayesha Kumar-Flaherty, Arlington, Virginia
Originally published in the October 2008 issue of American Baby magazine.
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