Prenatal DHA supplements
Those of you who know me know that I am very passionate about nutrition and discuss it at nearly every opportunity during our visits. A diet made up of whole, nutritious foods is of vital importance at every stage of life, though many of us first fully realize its value when we are pregnant and/or breastfeeding, and our growing baby is depending completely on us for their nutrition. Part of my work as an Integrative Pediatrician involves meeting with pregnant moms, and, during those visits, we talk about prenatal vitamins and supplements, including DHA.
What is DHA?
DHA (docosahexaenoic acid) is an omega-3 fatty acid found naturally in oily fish, such as wild-caught salmon, black cod, and sardines. It is thought to be important for brain and eye development, and, in recent years, many women have chosen to take DHA in the prenatal period.
Is there any evidence to indicate that taking DHA prenatally is necessary or even helpful?
The answer is YES!
Certain studies have shown that the children of mothers who took DHA supplements during pregnancy had increased sustained attention during the first year [1], as well as improved sustained attention once they reached preschool age [2], when compared to children whose mothers did not take DHA supplements prenatally. The DHA doses in these two studies were 600mg/day and 400mg/day, respectively.
Additionally, just as we recommend that moms continue taking their prenatal vitamin while they are breastfeeding, there is also evidence that taking a DHA supplement is beneficial in the lactation period. In one study, infants of moms who took a DHA supplement (in this case, 200mg/day) for four months during breastfeeding performed significantly better on a developmental assessment [3].
If allergies run in your family, then it may be even more important to take a DHA and fish oil supplement! One study that looked specifically at children who had a family history of allergies found that the babies of women who took fish oil during pregnancy and lactation had a decreased risk of infant allergies. Additionally, during the first 12 months of life, babies born to mothers in the omega-3 (fish oil) group had a decreased risk of developing food allergies and eczema. These findings suggest (but do not prove) that taking a fish oil supplement may decrease the risk of food allergy and eczema during the first year of life in infants with a known family history of allergic disease. [4]
It is important to be careful not to draw conclusions from a single study. One study is certainly informative, but in the case of DHA, for example, the studies have been mixed, thus far, with some studies’ showing benefit and others not. If larger studies are able to reproduce the results of these smaller ones, we may be able to draw more conclusions.
How much DHA should I take?:
Based on the information available to us now, I recommend taking a daily fish oil supplement with approximately 1g (700-1000mg) of total fish oil that contains approximately 400mg (200-500mg) of DHA, if you are not able to meet your needs with 2-3 servings of a low-mercury fish (like wild caught salmon or sardines) per week. I also emphasize the importance of healthy food choices overall, such as following a diet like the Mediterranean diet.
How do I choose a supplement?:
Since fish oil can be contaminated by heavy metals and environmental toxins, it is important to choose a preparation made by a reputable company that has been independently tested. For example, molecularly distilled fish oils are naturally high in both EPA and DHA and low in contaminants. [5]
I also recommend choosing a supplement that requires the fewest number of pills/spoonfuls to achieve the target dose, to make the regimen as easy as possible to incorporate into your daily routine.
An additional important aspect of fish oil to keep in mind is that, as with many things, more is not necessarily better. Though larger doses are used to treat certain conditions, they should not be taken in pregnancy except under the supervision and guidance of your physician, as larger amounts of fish oil may lead to adverse effects, such as bleeding problems [6].
Troubleshooting:
Nausea, upset stomach, and burping are known side effects of taking a fish oil supplement. Though they sound somewhat benign, these effects can often be quite unpleasant and can sometimes lead to discontinuation of the supplement entirely. If any of these occur, keeping your supplement in the freezer or using enteric-coated preparations can really improve these symptoms [7].
References:
Colombo J, Gustafson KM, Gajewski BJ, et al. Prenatal DHA supplementation and infant attention. Pediatr Res. 2016 Nov;80(5):656-662.
Ramakrishnan U, Gonzalez-Casanova I, Schnaas L, et al. Prenatal supplementation with DHA improves attention at 5y of age: a randomized controlled trial. Am J Clin Nutr. 2016 Oct;104(4):1075-1082.
Jensen CL. Effects of n-3 fatty acids during pregnancy and lactation. Am J Clin Nutr.2006;83(6 suppl):1452S–1457S.
Furuhjelm C, Warstedt K, Larsson J, et al. Fish oil supplementation in pregnancy and lactation may decrease the risk of infant allergy. Acta Paediatr. 2009;98:1461–1467.
Weil, A, Becker, B. Fish Oil and Omega-3. Jan 10 2013, http://www.drweil.com/vitamins-supplements-herbs/vitamins/fish-oil-and-omega-3/ Accessed: Oct 31, 2016.
Mayo Clinic. Omega-3 fatty acids, fish oil, alpha-linolenic acid. Mayo Clinic, The Natural Standard. Nov 1, 2013, http://www.mayoclinic.org/drugs-supplements/omega-3-fatty-acids-fish-oil-alpha-linolenic-acid/background/hrb-20059372 Accessed: Oct 31, 2016
Science Daily. Cardiovascular Benefits of Omega-3 Fatty Acids Reviewed. Mayo Clinic. Mar 12 2008, https://www.sciencedaily.com/releases/2008/03/080310164906.htm Accessed: Oct 31, 2016.