The study, published in the Journal of Physiology, reports the link between maternal intake of omega-3 polyunsaturated fatty acids (PUFAs) and the risk of developing allergies, finding that a mother's diet containing high amounts of omega-3s – such as those found in fish, walnut oil or flaxseed – cause the baby's gut to develop differently.
“In this study, we demonstrated that supplementation of the maternal diet with a particular fatty acid, 18:3 omega-3, the precursor of the omega-3 fatty acid family, modified intestinal permeability, probably via diet-induced neuroplastic changes of the enteric nervous system of newborn piglets,” said the researchers, led by Dr Gaëlle Boudry, of the INRA research institute in Rennes, France.
“These findings suggest that feeding fatty acids of the omega-3 family during pregnancy and lactation impact newborn intestinal barrier function,” they added.
Boudry added that such changes “are likely to reduce the risk of developing allergies in later life."
Omega-3 & allergy
Previous clinical trials have suggested that fish and walnut oil supplementation in pregnant women could reduce the risk of allergy in children; however, the mechanism for such benefits remains unknown.
Boudry said that intense research into such links was continuing in the hope of further establishing such an association and elucidating such a mechanism. She added that in the western diet omega-3 PUFAs – which her team has shown to help gut function – “are actually disappearing.”
“Our dietary intake of fish and nut oils is being replaced by corn oils which contain a different kind of fatty acid,” she said, as such, it is important to establish the benefits of these fatty acids so that they can be re-introduced into the maternal diet, added the researchers.
Female pigs received either a control diet (lard based) or an omega–3 (linseed oil based) diet during gestation and lactation. The researchers then assessed offspring gut functioning at 3, 7, 14, 21 and 28 days postnatal, finding that gut permeability increased significantly and similarly in both groups until 14 days, and decreased thereafter.
However, at 28 days, they found that permeability was higher in omega–3 PUFA group compared to controls.
The finding that supplementing a mother's diet with omega-3 caused the new-born's gut to become more permeable offers an explanation for the previous findings that omega-3s reduce the incidence of childhood allergy, said Boudry, noting that a more permeable gut enables bacteria and new substances to pass through the lining of the gut into the bloodstream more easily. These new substances then trigger the baby's immune response and the production of antibodies.
"The end result is that the baby's immune system may develop and mature faster – leading to better immune function and less likelihood of suffering allergies," she said.
However the team added that their study was based on piglets, so research will continue to see if the findings translate to humans. They added that the pig intestine is an excellent model of the human gut, however, so they are hopeful that the findings can be extrapolated.
The team also plans to investigate whether the apparent gut function-boosting effects of omega-3 PUFAs they have identified in new-borns extends into later life.
Source: The Journal of Physiology
Published online ahead of print, doi:10.1113/jphysiol.2011.214056
“n–3 polyunsaturated fatty acids in the maternal diet modify the postnatal development of nervous regulation of intestinal permeability in piglets”
Authors: F. De Quelen, J. Chevalier, M. Rolli-Derkinderen, J. Mourot, M. Neunlist, G. Boudry