Nutrition and Pregnancy: Foods to say “no” to

OK, so we’ve covered how eating a healthy diet is super important when you’re pregnant, or planning to become pregnant in the near future. I’ve talked about how a healthy pregnancy diet doesn’t look all that different than a healthy diet for non-pregnant people, except that:
  1. Pregnant women need eat enough extra nutritious food that they gain enough weight to support their increased needs for blood and tissue growth, as well as the needs of their growing fetus. How much weight gain is optimal will depend on a woman’s weight when she becomes pregnant.
  2. Certain nutrients are needed in larger-than-normal amounts before and/or during pregnancy.
So that’s what to eat…what about what not to eat? That’s easy (sort of): Certain types of seafood, and foods that increase your risk of foodborne illness.
Let’s start with the seafood, shall we? Many people (not just pregnant women) are aware that fish and other seafood can contain mercury, and that mercury is bad for you. That’s true…except that fish is very good for you. Mercury can harm brain development, but the types of fats found in fish are necessary for optimal brain development. So what to do? Eat fish and seafood, but do it smartly. The basic rules are this:
  • Don’t eat shark, swordfish, king mackerel, or tilefish. These fish contain high levels of mercury. 
  • Eat up to 12 ounces (two average meals) a week of a variety of fish and shellfish that are lower in mercury. For example, shrimp, canned light tuna, salmon, pollock, and catfish. 
  • Do you prefer canned albacore (“white”) tuna? Be aware that it has more mercury than canned light tuna (albacore is a bigger fish, and mercury has more chance to accumulate in it). So, don’t eat more than 6 ounces of albacore tuna per week, out of your total 12 ounces.
  • Do you have friends or family who like to go fishing in local lakes, rivers, and coastal areas? Before eating their daily catch, check local advisories about the safety of fish caught from these areas. If you can’t find any advice, eat up to 6 ounces (one average meal) per week of those local fish, but don’t eat any other fish that week. 
  • If you have young children, follow these same recommendations when feeding them fish and shellfish, but serve smaller portions.
Now on to foodborne illness, a most unpleasant topic for anyone, but a particularly critical one for pregnant women. During pregnancy, a woman and her unborn child are especially vulnerable to bacteria, viruses and parasites that cause foodborne illness. A classic example is Listeriosis, or infection by the bacteria Listeria. Listeriosis can produce few symptoms in some people, but have devastating effects in others. One in six cases of Listeriosis happen during pregnancy, bringing a very real risk of miscarriage or stillbirth. The Centers for Disease Control and Prevention has a Listeria page.
Foods to avoid include:
  • Unpasteurized (raw) milk or juice
  • Soft cheeses made from raw milk, like Brie and queso fresco
  • Salads made in a store, such as chicken salad
  • Raw cookie dough
  • Raw shellfish, like oysters or clams
  • Raw or undercooked fish, like sushi
  • Raw or undercooked sprouts
There is also a list of foods to be very careful with, such as lunch meats, hot dogs, turkey stuffing and homemade eggnog and ice cream. I encourage you to check out the list on
On a semi-personal note, in the past I have been a moderate raw milk advocate. That is, I believed I was making the healthier choice by drinking it myself, but I didn’t encourage other people to drink it if they weren’t already seriously entertaining the idea. While I still think that people should  have the choice to purchase and drink raw milk and raw milk cheeses (produced by farmers who follow strict guidelines), and I think these foods can be safe, the reality is that when you don’t pasteurize, you remove one huge part of the anti-pathogen safety net. That net does also includes good hygiene for people, animals and every part of the farm and milking facilities, but still…taking away pasteurization is huge. For certain vulnerable people (pregnant women, small children, the elderly, people with chronic illness or otherwise compromised immune systems), the risk is just too great.
I don’t buy raw milk anymore. I do make a point of buying local milk, as I’m not a fan of mega-industrialized agriculture. Because I choose to consume animal products, I try to make sure that the animals are treated well. That was one of the main reasons I bought raw milk to begin with, and once I looked into the research and found that there were no particular benefits to drinking raw  milk, the potential added risk of not pasteurizing was  no longer worth it. And I’ll be stepping off my soapbox, now. 
Next time: Why what goes on in the uterus today will still matter in 30 years