Some foods contain chemicals or bacteria that may pose a danger to both you and your developing baby. These hazards can interfere with optimal fetal development and growth, or cause serious infection, illness, or miscarriage.
Some fish, particularly large fish at the top of the food chain, contain dangerous levels of mercury, and other heavy metals, which can pass from the mother to fetus cause mercury poisoning, and fetal brain damage.
Fish with high levels of mercury that pregnant women should NOT eat:
- King Mackerel
- Albacore Tuna
The following fish have moderate levels of mercury. Limit to 1-2 servings per week during pregnancy.
- Sea Bass
- Canned light tuna
- Fresh Tuna
- Blue Fish
- Maine Lobster
- Salmon, farmed
Other Food Sources of Mercury and Other Heavy Metals
Rice and Rice Products from China
Because of escalating, widespread water contamination caused by industrial waste pollution throughout China, imported rice from China may have dangerous levels of mercury. According to a report published by the “Environmental Health Perspectives” in 2010, 7 percent of adults living in Wanshan province in China had blood levels of methylmercury that exceeded health limits. The report found that bacteria in rice paddies converted mercury into the more dangerous methylmercury.
While some types of fish contain methylmercury, the Omega-3 fatty acids have been found to have neuro-protective effects that rice lacks, making rice grown in China potentially more dangerous to eat than fish.
Rice Milk and Arsenic
Rice absorbs more arsenic from soil that other grains. Arsenic is a known carcinogen. Consumer Reports has estimated that adults drinking just ½ cup of rice milk could exceed health limits on arsenic exposure, and advises that children under the age of five, should not consume any rice milk, or products made with rice milk.
To stay safe, pregnant and lactating women should NOT consume any rice/rice products grown in China, or rice milk.
High Fructose Corn Syrup and Mercury
High fructose corn syrup (HFCS) is a common sweetener found in numerous processed foods such as jams/jellies, bread, BBQ sauce, salad dressings, cookies and other desserts, and soda. The average American consumes 50 grams of this sweetener a day.
The manufacturing of HFCS may include use of a chemical called mercury cell chlor-alkali. One study, published by Environmental Health found mercury in nine out of twenty foods sampled, and in a second study, as many as 33% of food samples had measureable amounts mercury where HFCS was listed as either the first or second ingredient.
Because Americans consume so much HFCS, the accumulation of mercury over time may be a major, but as yet unrecognized, health concern. In light of this, limiting or eliminating consumption of products that contain HFCS during pregnancy is prudent.
Dangerous Bacteria: Salmonella, Listeria and E. coli
Raw and undercooked meats, fish, and eggs may contain salmonella, or other potentially dangerous bacteria. In healthy adults, these bacteria cause vomiting, fever, and diarrhea. But for pregnant women, these bacteria can cause miscarriage, stillbirth, or premature delivery.
Another dangerous and potentially deadly bacteria, Listeria, can be found in deli meats, soft cheeses, unpasteurized milk and dairy products, and unpasteurized juices.
Listeria can cause a deadly infection that can cross the placenta and sicken your developing baby. Pregnant women, who wish to consume deli meats, should always heat the meat to 165° F before eating.
Listeria bacteria can be found in soft unpasteurized cheeses including as Brie, Feta, Gorgonzola, Camembert, and Roquefort. Other unpasteurized products such as “raw” cheese, and fresh apple cider are also off the prenatal menu.
Unwashed fruits and vegetables may also put you at risk to exposure to harmful Listeria and E. coli bacteria. Unfortunately, the rate of widespread outbreaks of food borne illnesses in the US continues to increase. To stay on the safe side, pregnant women should always wash all fruits and vegetables before eating.
Because of the potential of contamination, the March of Dimes advises moms-to-be to forgo salad bars and packaged green such as spinach, lettuce, spouts, as these have been linked to outbreaks of contamination, severe illness, and death.
Washing fruits and vegetables with warm water and soap before eating or preparing with kill most bacteria. Pregnant women should always wash all produce before preparing and eating.
To stay on the safe side, always read labels carefully, and ask about the foods you order in restaurants. When in doubt, don’t eat it.