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Journal Article

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Crowley, E. T., Williams, L. T., Roberts, T. K., Dunstan, R. H., & Jones, P. D. (2012). Does milk cause constipation? a crossover dietary trial. Nutrients, 5(1), 253-266.

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© Copyright, The Authors, 2013

2013 HERDC Submission. FoR code: 111100

This work is licensed under a Creative Commons Attribution 3.0 License




The aims of this study were to: (1) determine whether replacement of cow’s milk protein with soy resolves Chronic Functional Constipation (CFC); and (2) investigate the effects of cow’s milk â casein A1 and cow’s milk â casein A2 on CFC. Children diagnosed with CFC were recruited to one of two crossover trials: Trial 1 compared the effects of cow’s milk and soy milk; Trial 2 compared the effects of cow’s milk â casein A1 and cow’s milk â casein A2. Resolution of constipation was defined as greater than eight bowel motions during a two week intervention. Thirteen children (18 to 144 months) participated in Trial 1 (6 boys, 7 girls). Nine participants who completed the soy epoch all experienced resolution (p < 0.05). Thirty-nine children (21 to 144 months) participated in Trial 2 (25 boys, 14 girls). Resolution of constipation was highest during the washout epoch, 81%; followed by cow’s milk â casein A2, 79%; and cow’s milk â casein A1, 57%; however, the proportions did not differ statistically. The results of Trial 1 demonstrate an association between CFC and cow’s milk consumption but Trial 2 failed to show an effect from type of casein. Some other component in cow’s milk common to both A1 and A2 milk may be causing a problem in these susceptible children.



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