Exposes about food contamination have been the subject of socially and nutritionally minded authors for hundreds of years. In 1906 Upton Sinclair wrote the book “The Jungle” which detailed the horrible conditions in Chicago’s meat packing houses. (Remember he wrote about workers who fell into rendering tanks and were ground along with animal parts!) Although conditions for the workers (but not necessarily the cows) have vastly improved, contamination of meat products (usually from bacteria) as well as vegetables and fruit are still common, especially as food sources go global. (Do you know where your strawberries come from? What about your fish?) And when a particular pathogen enters the food chain and causes sickness or death to the consumer, it enters so many widely distributed products that identifying its final “resting place” (other than the GI system of the unfortunate person who ate it) requires extraordinary food surveillance. The CDC estimates that 5,000 Americans die from 76 million cases of food-borne illness in the United Stated every year. The most susceptible are the very young, the very old, the immunocompromised, pregnant women and their fetuses.
Pregnancy can diminish immune resistance and an unfettered infection can cause miscarriage as well as fetal malformations, disability, illness and death to the newborn. Hence food safety and safe food choices are especially important in pregnancy. Here are some of the food-borne pathogens and the foods that may contain them that merit special attention…
This bacterium is usually killed by pasteurization and cooking. It can, however be airborne and contaminate treated foods. And to make matters worse it can grow inside a refrigerator!
Foods likely to be contaminated: Unpasteurized milk products, refrigerated and ready-to-eat- products (dairy, meats, poultry and seafood and deli products). The prevalence of Listeria in these foods is estimated to be nearly 2%. Food packaged in the store is less safe than that packaged by the original manufacturer.
Symptoms: Typically mild…low grade gastroenteritis, or flu like symptoms. More serious infection (called listeriosis) causes vomiting, abdominal pain, diarrhea with fever and in some cases meningitis and overwhelming infection (septicemia). Pregnant women are 20 times more likely to develop listeriosis than all other individuals, indeed one third of all cases occur during pregnancy. And even if the initial symptoms are mild, the bacteria may cross the placenta and infect the fetus.
The FDA and CDC have issued guidelines for safe eating in pregnancy in order to avoid listeria infection. These include:
* Avoid cross-contamination with fluid from hot dog packages.
* Keep raw meets separated from vegetables, cooked food and ready-to-eat foods.
* Eat perishable foods as soon as possible.
* Throw out expired food.
* Wipe spills immediately and clean the refrigerator regularly with hot water, liquid detergent and then rinse.
* Eat lower risk food and avoid unpasteurized milk or any foods from raw milk!
* Don’t eat hot dogs, luncheon meats or deli meats unless reheated or steamed. Don’t eat refrigerated pates or meat spreads. (OK if canned)
* Don’t eat refrigerated smoked seafood unless it’s in a cooked dish. These are often labeled “nova-style”, “smoked”, “kippered” or “jerky”. (So there goes that bagel, cream cheese and lox…I guess the bagel and cream cheese can stay as long as the latter is pasteurized!)
This is a parasite which can cross the placenta and cause surviving children to have long-term problems (specifically serious eye and brain damage). Most pregnant women have no symptoms when infected. The fetus is at risk if the mother is exposed just before or during her pregnancy, but is unlikely to become infected if the mother has had the infection in the past. (This can be checked with a special antibody test; however, the test is not routinely done in the US because there are no established effective treatments.)
Food Sources: Contaminated meat, especially wild game (if undercooked or raw), unpasteurized milk, unwashed fruits and vegetables, contaminated water.
Other Sources: Cats are hosts to this parasite and become infected if they are kept outdoors, hunt and/or eat raw meet. They excrete the toxoplasmosis as cysts or eggs in their feces. The chance of infection from a cat is low if it is kept indoors, doesn’t hunt or eat raw meat. (Cat food manufacturers know this.)
Here are the CDC guidelines to prevent Toxoplasmosis infection:
* Freeze meat for several days before cooking
* Cook meats to at least 160 degrees (or higher to kill other pathogens). Note meats that are smoked, cured in brine, or dried may still be infectious.
* Keep children’s sandboxes covered.
* Wear gloves when gardening or handling sand in sand boxes.
* Peel and thoroughly wash fruits and vegetables before eating.
* Keep your cat indoors; don’t feed it raw or undercooked meats or unpasteurized milk
* If possible have someone else change the litter box, if not, wash your hands and disinfect the litter box daily with near boiling water for 5 minutes.
* Don’t get a new cat while pregnant or handle stray cats, especially kittens.
* Don’t drink unpasteurized milk, including goat’s milk.
* Don’t drink water from the environment unless it’s boiled. (I guess they mean water from rivers and streams…. This seems like a good idea in general.)
* Control rodents (I won’t comment on this one).
* If you butcher wild game or venison, bury the organs so that feral cats can’t eat them and spread infection. (I guess this applies to very few of us, oh, but wait…there’s Sarah Palin!)
This is where raw sushi and sashimi get boycotted by pregnant women. Raw fish can harbor parasites such as roundworms, tapeworms and flatworms as well as bacteria and viruses. And don’t forget, ceviche (fish prepared in acid and not really cooked) is included in the raw category. If you do dine in a Japanese restaurant during pregnancy order the vegetable or cooked sushi, although some purists might worry that these are prepared with the same utensils as the raw stuff. Maybe you should just get the teriyaki or the noodle soup…
Just when you thought that you could and should consume healthy vegetables such as sprouts (alfalfa, clover and radishes), I have disappointing news. It turns out that sprouts have been found to contain E.coli and Salmonella. (A 2007 survey of retail foods in the US found a bad strain of E.coli in 1.5% of alfalfa sprouts compared to 0.17% of ground beef that they sampled!). Sprouts are produced under warm, moist conditions which encourage the growth of bacteria. They become internalized in the seed during sprouting. So washing doesn’t remove the bacteria! The only safe way to eat sprouts during pregnancy is to cook them.
So many chickens live in crowded squalor, infecting one another and their eggs with salmonella. The current estimates are that 1/20,000 eggs contain this bacteria. We are not talking abstention here….just cook the egg until the whites and yolks are firm. If you are making Cesar salad or a food that requires raw egg, use pasteurized egg. And always wash you hands after handling eggs.
Strictly speaking, this legume should not be part of a discussion of contaminated foods. But peanut allergy is such a concern, I have included it in this article.
Should a pregnant woman avoid eating peanuts in order to diminish the risk of peanut allergy in her child? We used to tell pregnant women that this was a forbidden nut. But statistics subsequent to this admonition have shown that it doesn’t seem to make a difference and peanut allergy in children has increased. Indeed a 2008 study showed that sensitization does not appear to occur from intra uterine exposure. According to the American Academy of Pediatrics there is a lack of evidence that maternal dietary restrictions during pregnancy play a significant role in the prevention of peanut (and other) allergies in infants. So if you have some peanut butter, don’t feel guilty.
Municipal water is generally very safe in the US. (Although I probably should modify this statement… there was a recent article in the New York Times that exposed water contamination that was not reported nor efficiently dealt with by the EPA….mostly in smaller communities.). Most bottled water does not contain fluoride which will benefit the future teeth of the developing fetus. And if water is sold in certain types of plastic containers it can become contaminated with potentially harmful chemicals.
I have not dealt with “the fish or no fish” debate (other than the raw kind) nor have I begun to discuss organic versus non organic, processed food, fats or caloric intake. I’ll leave all that for another article (or more). But I hope that the above gives you (if you are pregnant) or someone you care about (i.e. daughters, relatives and friends) a sense of which foods and food preparations are potentially harmful to a pregnant women and her baby. When it comes to contamination and infection, she is eating for two.