The aim of this study was to investigate how maternal polyunsaturated fatty acid intake at different periods during pregnancy affects the composition of polyunsaturated fatty acids in mature human milk.
A prospective study was conducted involving 45 pregnant women, aged between 18 and 35 y, who had full-term pregnancies and practiced exclusive or predominant breast-feeding. Mature breast milk samples were collected after the 5th postpartum week by manual expression; fatty acid composition was determined by gas chromatography. Fatty acid intake during pregnancy and puerperium was estimated through multiple 24-h dietary recalls. Linear regression models, adjusted by postpartum body mass index and deattenuated, were used to determine associations between estimated fatty acids in maternal diet during each trimester of pregnancy and fatty acid content in mature human milk.
A positive association was identified between maternal intake of eicosapentaenoic acid (β, 1.873; 95% confidence interval [CI], 0.545, 3.203) and docosahexaenoic acid (β, 0.464; 95% CI, 0.212–0.714) during the third trimester of pregnancy, as well as the maternal dietary ω-3 to ω-6 ratio (β, 0.093; 95% CI, 0.016–0.170) during the second and third trimesters and postpartum period, with these fatty acids content in mature breast milk.
The maternal dietary docosahexaenoic acid and eicosapentaenoic acid content during late pregnancy may affect the fatty acid composition of mature breast milk. Additionally, the maternal dietary intake of ω-3 to ω-6 fatty acid ratio, during late pregnancy and the postpartum period, can affect the polyunsaturated fatty acid composition of breast milk.
Alex’s notes: The long-chained polyunsaturated fatty acids (PUFAs) DHA, EPA, and ARA (arachidonic acid) are incredibly important to the growth and development of infants. And where do these fats come from? The mother’s breast milk. This is an area where the old adage “you are what you eat” could not be truer, as the fatty acid content of breast milk varies greatly depending on the diet of the mother, and it has been shown that fish oil supplementation alters the EPA/DHA content of breast milk. The study at hand sought to further our understanding of these changes by looking at how the intake of PUFAs during different trimesters of pregnancy impacted breast milk composition in normal weight and healthy women between 18 and 35 years old.
25% and 33% of the EPA and DHA in breast milk, respectively, was associated with intake during the third trimester, and 22%, 15%, and 12% of the omega-3 to omega-6 ratio in breast milk was associated with intakes during the second and third trimesters, and the postpartum period, respectively. At no time during the pregnancy or afterwards was dietary intake of alpha-linolenic acid (ALA), linoleic acid (LA), total omega-3 or omega-6 content associated with the fatty acid composition of breast milk.
This was a simple study that provided some prudent insight. Once you’re pregnant, you have about 11 weeks to get your diet in check before you start influencing your milk composition, and at 30 weeks you better be eating salmon 3-4x per week. Of course, being the Super Humans we are, this shouldn’t pose an issue.