At present, there is a major marketing effort aimed at getting pregnant and breastfeeding women to take DHA supplements (the same supplements that are being marketed in the newer baby formulas).
Here’s a quick rundown on what DHA is: Mammals do not manufacture their own polyunsaturated fatty acids. Two of the polyunsaturated fatty acids, Omega-6 (linoleic acid is the primary source) and Omega-3 (alpha-linolenic acid is the primary source), are considered to be essential fatty acids (EFAs) and have numerous health benefits. Deficiencies of either of these essential fatty acids are extremely rare in the United States and Canada. We convert these essential fatty acids in our bodies to other needed fatty acids, which we can also get from food sources. Gamma-linolenic acid (GLA) and arachidonic acid (ARA) are made from linoleic acid; and alpha-linolenic acid (ALA), eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) are made from alpha-linolenic acid.
Babies, however, generate the fatty acids such as ARA and DHA more slowly than adults and thus need to get some via diet (i.e., breastmilk). In addition, there is evidence that adults eating a typical American diet do not get a large enough percentage of the Omega-3 fatty acids.
There is no evidence whatsoever that breastmilk is deficient in DHA, and there is no evidence that DHA supplements taken by a nursing mother will improve the long term outcome or IQ of her baby. Nursing mothers who get more DHA do have have higher levels of DHA in their milk, but it is not known whether these higher levels are beneficial or what the optimal levels might be. Vegetarians, particularly vegans, tend to have lower levels of DHA in breastmilk.
Dr. Thomas Hale recommends that normal breastfeeding women should not be supplemented with polyunsaturated fatty acids (PUFAs). He indicates that while it is true that populations who ingest large quantities of fish and therefore polyunsaturated fatty acids do not have cardiovascular disease, he has indication that their rate of stroke is much higher, and so recommends that “supplements” not be used.
Nursing and pregnant women are certainly encouraged to eat natural sources of DHA and alpha linolenic acid. Good sources include:
- cold water/oily fish and fish oils (e.g., salmon, mackerel, herring, tuna, sardines, anchovies); fresh fish is better, as freezing destroys some of the EFA; avoid consumption of fish that may be high in mercury
- green leaves of plants, including phytoplankton and algae
- some seeds and nuts (flax seeds, walnuts, canola, linseeds, pumpkin seeds)
- some legumes (soy beans, Great Northern beans, kidney beans, navy beans)
Dietary Choices and DHA Supplementation from LLL’s LEAVEN, Vol. 34 No. 5, October-November 1998, p. 102-103.
DHA Levels in Breastmilk by Ricardo Uauy, a researcher in Chile
DHA (docosahexaenoic acid) from AskDrSears.com (Dr. Sears is associated with Martek, a manufacturer of DHA supplements)
Scientific Backgrounder on DHA and Pregnancy/Lactation from Martek Biosciences Corporation (manufacturer of DHA supplements)
General info (not lactation related)
Essential Fatty Acids in Vegetarian Nutrition by Brenda Davis, RD (great reading even if you are not a vegetarian)
Essential Fatty Acids by Christine Wood, MD, from KidsEatGreat.com