The discovery that DHA (docosahexaenoic acid) from breast milk promotes healthy brain, eye, and nervous system development was an important step towards understanding why breast milk is a perfect first food for babies. DHA is now commonly added to infant formulas, but it’s not the only fatty acid that is important for developing babies. A new study shows that other fatty acids in breast milk may protect them from allergies.
The sharp rise in allergic diseases like asthma, eczema, food allergies, and hay fever might be explained in part by a shift in the fatty acid balance in our diets. The widespread use of vegetable oils and the comparatively low intake of omega-3 fatty acids (mostly from fish) have tipped the scales in favor of omega-6 fatty acids, which contribute to inflammation in the body.
Does breast milk affect eczema?
As part of the KOALA Birth Cohort Study, scientists investigated the composition of breast milk and its relationship to eczema and allergy development in 310 infant-mother pairs. Based on earlier findings that organic dairy seems to protect against eczema during the first two years, some of the women included led “alternative lifestyles,” meaning that they ate organic foods and breast-fed for an extended period. Researchers were interested to see how the fatty acid composition of their breast milk compared with that of moms who ate a more conventional diet.
Information related to breast-feeding, eczema, and other allergic diseases was gathered from the women while they were pregnant and during the first two years after birth. Blood samples were taken from the babies at one and two years to determine the presence of allergies to things like hen’s eggs, cow’s milk, peanut, tree and grass pollen, dust mites, and cats and dogs.
Babies benefit from fatty acid combo
Compared with the conventional diet group, the breast milk of moms with alternative lifestyles had somewhat higher concentrations of the omega-3 fatty acids EPA (eicosapentaenoic acid), DPA (docosapentaenoic acid), and DHA. The breast milk from this group was also higher in ruminant fatty acids (those derived primarily from dairy fat), including the immune-enhancing fatty acid, CLA (conjugated linoleic acid).
“Differences in fatty acid status between mothers may modify the protective effect of breastfeeding,” said Dr. Carel Thijs, lead author of the study from the Department of Epidemiology at Maastricht University in the Netherlands. “This may explain inconsistencies between studies in different populations with different intakes of fish, ruminant fats, and trans fatty acids from other sources.”
More interesting results:
By age two, 31% of the babies had parent-reported eczema, and 42% of the children with eczema also had allergies as determined by blood tests.
The risk of eczema and allergies at one year was lowest among babies whose mothers’ milk was highest in omega-3 fatty acids.
The risk of eczema and allergies also decreased with increasing concentrations of ruminant fatty acids, independent of the effect of the omega-3 fatty acids.
“Ruminant fatty acids deserve further investigations for their role in early immune development and are potential candidates to explain the protective effects of dairy fat as well as organic dairy and possibly unpasteurized farm milk on the development of atopic (allergic) conditions in early life,” the researchers concluded.
How to protect your baby from eczema
Breast-feed, if you can. For some women breast-feeding isn’t feasible, but it’s worth it for your baby’s health if you’re able to.
Eat more fatty fish. This is important during pregnancy and while breastfeeding. Avoid high-mercury fish including swordfish, shark, albacore tuna, king mackerel, tile fish, grouper, marlin, and orange roughy.
Make it creamy. The latest study adds to a growing body of evidence of the inflammation-fighting potential of full-fat dairy products.
(The study comes from Allergy 2011;66:58-67)
