Thirty five weeks into this pregnancy and with the weight piling on, fat is probably the last word I want to hear right now! But, what is nice to hear is this…pregnancy is not a time to skimp on eating healthy fats. I’m sure you’ve heard some fats are better than others, so which fats do you need during pregnancy? Omega-3’s! They're considered essential fatty acids because you have to acquire them from food or supplements. Your body won’t make them or anything fancy like that.
One omega-3 you may have heard of is DHA (known in the science world as docosahexaenoic acid). DHA is especially important during pregnancy because it's absolutely vital for that unborn baby’s brain and eye development, nervous system, and immune system (1, 2, 3). Along with benefits to baby, a pregnant mom consuming omega-3’s reduces her risk of pre-term labor, pre-eclampsia, and possibly post-partum depression (2, 3).
Fish is the most likely source of omega-3's; however, is there a dark side to the fish story??? Yes there is, and I personally LOVE fish, so this really bums me out!
Here’s the scoop…large, ocean-faring fish, and especially predator types, contain high levels of mercury, a distinctly baby-unfriendly toxin. Mercury easily crosses the placenta and accumulates in the fetus at even higher concentrations than in mothers (4-7). Other fish, especially those that frequent polluted lakes and rivers, are laden with PCBs, a chemical you definitely don't want to feed a growing fetus. To play it safe, keep all those types of fish off your plate while pregnant and breastfeeding. And to play it extra safe, consider these guidelines (8):
Fish to Avoid:
Shark, swordfish, king mackerel, ahi tuna, tilefish, orange roughy, and fish from contaminated waters
Limit to six ounces per week:
Canned (or packaged) albacore tuna, tuna steaks, grouper, sea bass, and freshwater fish caught by family and friends
Safely eat 12 ounces per week:
Wild salmon, shrimp, crab, sardines, freshwater trout, tilapia, canned (or packaged) light tuna, pollock, and catfish
Not a big fish lover?
Try DHA-rich eggs, sometimes called omega-3 eggs. They’re laid by chickens on a DHA-supplemented diet— it’ll say so on the package. Regular egg yolks contain a small amount of DHA too. Walnuts, flax seed, hemp seed, pumpkin seeds, chia seeds, kale, collard greens, and green algae are plant based sources of omega-3 fatty acids. Unfortunately, it is well-known only a small amount of the plant based omega-3 is actually converted to DHA in our bodies.
Choosing a supplement:
Another easy and consistent way to get enough DHA is taking a quality fish oil supplement. Some prenatal vitamins have DHA in them, but more than likely, there isn’t enough. It really is worth the additional cost of purchasing a high quality fish oil supplement to take alongside your prenatal vitamin. When you’re choosing a fish oil supplement, definitely examine the nutrition label to know specifically how much DHA you are getting. Get this… a 1000 mg fish oil soft gel refers only to the size of the soft gel, not the level of DHA. Very misleading! Look specifically for the number of mg of DHA. Quality fish oil is safe to take because toxins and heavy metals can be virtually eliminated during the manufacturing and processing of the fish oil. Remember to always refrigerate your fish oil.
The Anticipated Question...How Much DHA?
For pregnant and breastfeeding women, a minimum of 300 mg DHA daily (9). You're definitely not going to overdose on this natural fat, so I always error on the side of a little higher.
Bottom Line: Optimize you and your baby’s health by including fish in your diet and consider taking an omega-3 supplement, specifically one with at least 300 mg DHA.
In Health and Happiness,
Kelly Harrington, MS, RDN
Registered Dietitian Nutritionist for Healthy Goods
1. Dunstan J.A., Mitoulas L.R., Dixon G., Doherty D.A., Hartmann P.E., Simmer K., Prescott S.L. The effects of fish oil supplementation in pregnancy on breast milk fatty acid composition over the course of lactation: A randomised controlled trial. Pediatr. Res. 2007;62:689–694.
2. Morse NL. Benefits of Docosahexaenoic Acid, Folic Acid, Vitamin D and Iodine on Fetal and Infant Brain Development and Function Following Maternal Supplementation during Pregnancy and Lactation. Nutrients. 2012 July; 4(7):799-840.
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4. Kjellström T, Kennedy P, Wallis S, Stewart A, Friberg L, Lind B, et al. Physical and mental development of children with prenatal exposure to mercury from fish. Stage 1. Preliminary tests at age 6 [Report 3642]. Stockholm, Sweden: National Swedish Environmental Protection Board; 1989.
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7. Methylmercury. Environmental Health Criteria, No. 101. Geneva: World Health Organization; 1990
9. Simopoulos AP, Leaf A, Salem N. Conference report: workshop on the essentiality of and recommended dietary intakes for omega-6 and omega-3 fatty acids. J Am Coll Nutr 1999;18:487–9.