IGF1 and prostate carcinoma: High circulating concentrations of insulin growth factor‐I (IGF‐I) is a risk factor for prostate cancer,2, 3 and some evidence indicates that proteins in the diet, especially from dairy products, may be related to higher circulating IGF‐I concentrations.4, 5, 6, 7, 8, 9, 10, 11, 12