Saturday, November 29, 2008

Eating Fish Before, During, and After Pregnancy

In today's NYT Magazine, Alex Kuczynski details her adventures in choosing surrogate motherhood in her article "Her body, My Baby." After years of infertility, Kuczynski and her husband provided the egg and sperm to create the embryo, which was implanted inside of surrogate gestational-mom Cathy. Describing Cathy's visit to their NY house and her amazement at Cathy's piano skills, she states "I stood outside the living room, holding a tray of tuna sandwiches and listening."

Up until that point in the article, my thoughts focused on the emotional roller coaster the author was on while she endured multiple miscarriages and failed IVF treatments, along with the miracle of my son playing nearby. However, when I read that she served her surrogate placenta a tuna fish sandwich, my immediate thought was "I hope it was chunk light."

Not that eating a couple of sandwiches of regular solid white tuna, with its high level of mercury, during pregnancy will doom her child for poor health outcomes. Yet I was completely surprised that an educated and wealthy woman made no mention of food concerns for her fetus' placenta.

So what is the deal with fish?

Some researchers think that eating fish or fish oil high in omega 3 fatty acids will decrease natural killer cells and help women prevent miscarriages. If fish oil is consumed during pregnancy, some research indicates that your baby may have less eczema, wheezing, and asthma because of a reduction in cytokine activity, altering certain cells in cord blood, and altering fatty acid composition of breast milk. But the benefits of prenatal fish supplements on childhood cognition and behavior are mixed. This may be the result of using different types of supplements in the studies: marine algae oil is likely less beneficial than fish oil. Marine algae oil supplements are the kind used in infant formulas and are probably not as beneficial as fish oil. In adults, fish oil can help in the management of certain GI and autoimmune disorders.

While all of this sounds great, pregnant women, women trying to become pregnant, and children need to be concerned about taking in too much mercury, BCP's, and dioxins that get absorbed into the fat of fish- the exact location of the beneficial properties. These neurotoxins enter our food system through coal-fired power plants, waste incineration, and electrical equipment produced prior to 1970. Runoffs from these products get into the soil and waterways and make their way into placentas, breast milk, cow's milk and infant formula. From there, they make their way into the developing fetal/child brain and can lead to deficits in motor skills, language skills, learning and memory skills, and behavior problems. Some of these effects can persist through adolescence. Consumption in adults can lead to impaired fertility in both men and women.

What can you do about it?

Take a fish oil supplement during pregnancy, especially after 20 weeks. Although I was advised by my OB/GYN to take Expecta, a marine algae oil supplement, after reviewing the research I now only recommend fish oil supplements and will do so myself with my next pregnancy. Fish oil supplements often filter out toxins. Make sure that the brand you buy runs independent tests for impurities.

Since there are also many benefits of consuming actual fish, enjoy fish safely:
* Eat a variety of fish from a variety of waters.
* Limit consumption to 12 ounces of safe fish during pregnancy (see list below)
* Do not consume any shark, swordfish, king mackerel, or tilefish during pregnancy
* Observe fish and wildlife advisories in your area or when fishing
* If you eat more than 12 ounces one week, eat less than 12 ounces the next week
* Trim fat from fish
* Eat both farmed fish and wild fish. Wild fish are higher in omega 3's but also higher in dioxins.
* Small amounts of neurotoxins also exist in the fat of meat, dairy, and eggs so be sure to eat plenty of vegetables, whole grains, fruits, and beans/legumes.

BeyondPrenatal's Safe Fish List:

Due to the nature of our environment this list is subject to change!!!
This list includes fish low in mercury and PCB's but still relatively high in omega 3 fatty acids. This list in not all inclusive but includes most safe fish that are commonly consumed.

(~ = fish has fins and scales and is therefore kosher)

Canned chunk light tuna ~
Clams
Codfish~ (including cod, haddock, pollock, whiting) Note: Freshwater cod is not kosher
Crab
Flounders~ (including sole and halibut)
Mackerel ~ (only Chub Pacific, Chub South Australian, and Spanish South Atlantic)
Oysters
Scallops
Shrimp
Trout ~ (such as Salmon trout, Rainbow trout, etc...)

Sardines and Salmon are both excellent sources of omega 3 fatty acids but are high in PCB's and Dioxins. If you choose to eat them, limit to 6 ounces per week and eat no other fish that week. If you consume tuna steak or solid white canned tuna, eat only 6 ounces per week and eat no other fish that week.

Websites to check out:
http://www.epa.gov/waterscience/fish/
http://www.cfsan.fda.gov/~dms/admehg3.html
http://www.arhp.org/publications-and-resources/quick-reference-guide-for-clinicians/fish-and-health
http://www.montereybayaquarium.org/cr/cr_seafoodwatch/sfw_health.aspx
http://www.safeharborfoods.com/
http://www.edf.org/page.cfm?tagID=17694
http://www.food.gov.uk/science/surveillance/fsisbranch2006/fsis0306 (UK)
http://www.foodrisk.org/commodity/animal/fish_shellfish/

1 comment:

  1. Wow, I am really enjoying your blog! Thanks for all the great info! I was wondering if Tilapia is off the safe list? Thanks again!

    ReplyDelete