Organic meat and dairy linked to better quality breast milk
August 27, 2007
By Stephen Daniells//British Jouranl of Nutrition/July 25, 2007
The breast milk of mothers consuming organic meat and dairy contains higher levels of beneficial fatty acids, and has an overall improved quality, suggests new research.
The new study, published in the British Journal of Nutrition, reports that obtaining at least 90 per cent of dairy and meat products from organic sources increases levels of conjugated linoleic acid (CLA).
“We show here that the levels of both rumenic acid and trans-vaccenic acid (TVA) in human breast milk were higher in the case of mothers following a diet that contained organic dairy and meat products, in comparison with mothers consuming a conventional diet,” wrote lead author Lukas Rist from Paracelsus Hospital Richterswil in Switzerland.
“In view of the accumulating evidence pointing towards various positive effects of CLA on human health, in particular at a very young age, the present results are highly interesting,” he added.
The research, performed in collaboration with scientists from the University of Hamburg, Maastricht University, TNO Nutrition and Food Research, Louis Bolk Institute (Driebergen), Zurich University Hospital, adds to the debate between conventional and organic fruit that has raged with claim and counter-claim from both sides.
“These findings provide scientific support for common sense, by showing that organic foods are healthier,” said Rist.
“The study shows that breastfeeding mothers can influence the supply and quality of fatty acids for their infants, by eating a diet with organic dairy,” he added.
According to a study published recently in the Journal of the Science of Food and Agriculture, the world market for certified organic foods was estimated at $23-25 bn (€17.3-18.8 bn) in 2003 with annual growth of about 19 per cent.
Rist and co-workers took breast milk samples from 312 breastfeeding mothers taking par in the KOALA Birth Cohort Study. Dietary intakes of organic and conventionally produced foods was assessed using a 160-item food frequency questionnaire (FFQ).
The researchers report that the content of rumenic acid (the main CLA) increased significantly with increasing organic dairy and meat consumption. Indeed, rumenic acid content was 0.25 weight per cent for a diet containing no organic dairy and meat, and this increased to 0.34 weight per cent for a strict organic diet.
TVA levels also increased, going from 0.48 weight per cent for a diet containing no organic dairy and meat, to 0.59 weight per cent for a strict organic diet.
“Hence, the levels of CLA and TVA in human milk can be modulated if breastfeeding mothers replace conventional dairy and/or meat products by organic ones,” wrote the researchers.
“The health effects of CLA and TVA on human newborns are still unknown; nevertheless there is promising evidence stemming from animal models and from clinical studies involving human adults… An area in which the expectations concerning the CLA effects are relatively high concerns their immunomodulating properties,” they added.
“Further results of the KOALA Birth Cohort Study, in particular those concerning allergic sensitization and asthma in the children corresponding to the mothers that have participated in the present study, are awaited anxiously,” concluded the researchers.
The study is in-line with a recent review, published in the journal Nutrition Bulletin and authored by the British Nutrition Foundation’s Claire Williamson. For the dairy industry, Williamson quotes several studies that reported improved nutrient levels for alpha-linolenic acid (ALNA), conjugated linoleic acid, alpha-tocopherol (vitamin E), beta-carotene, and/or a higher proportion of polyunsaturated fatty acids (PUFAs) to monounsaturated fatty acids in the organically produced dairy.
Source: British Journal of Nutrition
April 2007, Volume 97, Issue 4, Pages 735-743
“Influence of organic diet on the amount of conjugated linoleic acids in breast milk of lactating women in the Netherlands”
Authors: L. Rist, A. Mueller, C. Barthel, B. Snijders, M. Jansen, A.P. Simoes-Wust, M. Huber, I. Kummeling, U. von Mandach, H. Steinhart and C. Thijs