Modern milk production on an industrial scale involves administration of various synthetic substances to dairy cows to enhance milk production. The dairy milk has significant residues of these synthetic substances such as hormones, antibiotics and analgesics . Sadly, these negative aspects of ‘mass produced milk’ has not been discussed in the paper at all .
For instance, the paper deals with cohorts recruited between 1987 and 1997. But until the European wide ban in 2000, recombinant bovine somatotropin (rBST) was used to enhance milk production. The hormone rBST can affect hormonal and metabolic growth factors including human serum insulin-like growth factors (IGF) which in turn can increase the risk of cancer . A large European cross-sectional showed that intake of dairy was an important dietary determinant of serum IGF-I .
Analysis of milk for presence of these substances would have provided a more plausible explanation for the mortality effect.
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Competing interests: No competing interests