A 15-year, global study (TRIGR) of 2,159 children with a Type 1 relative, involved different types of formula fed to the children in early months.
"Approximately half were weaned on an adapted cow's milk formula and the other half were weaned on extensively hydrolysed casein formula."
"The results showed that fewer children in the cow's milk formula group developed type 1 diabetes than those having the extensively hydrolysed casein formula. In terms of statistical difference, there was deemed to be no difference in type 1 diabetes development between the two groups."
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https://globalnews.ca/news/3968687/cows-milk-and-type-1-diabetes-international-study-disproves-link/
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https://www.trigr.org/documents/PressRelease_JAMA_2018-Jan-02.pdf
(I don't know that this entirely disproves cow's milk as a contributor, as different people against cow's milk claim multiple theories: that it's the bovine insulin that's similar to humans that is getting rejected and causing autoimmunity; or that the milk proteins enter through some kind of leaky gut syndrome; or whatever inflammation they claim is caused by cheese and milk products because "humans are the only ones to regularly ingest the milk of other animals...." Just FYI -- this particular milk protein study said no difference occurred.)
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