Milk and Dairy Consumption
A study published in the European Journal of Clinical Nutrition found that elevated insulin-like growth factor-I (IGF-1) levels were positively associated with the consumption of protein (mainly from animal sources), milk, cheese, calcium, magnesium, phosphorous, potassium, and vitamins B2 and B6. The study examined 2,109 women from eight European countries who had been subjects in a preceding breast cancer study (the European Prospective Investigation into Cancer and Nutrition). Inverse relationships were found between IGF-1 levels and the intake of vegetables and beta-carotene (found in orange-colored fruits and vegetables as well as dark leafy greens). Previous evidence has revealed that elevated IGF-1 levels are associated with a variety of cancers, including colorectal, prostate, and premenopausal breast cancer.1
The American Journal of Clinical Nutrition published results of a 65-year follow-up study showing dairy consumption affects biological pathways associated with carcinogenesis. They found a diet rich in dairy products during childhood is associated with a greater risk of colorectal cancer in adulthood. High childhood total dairy intake was associated with a near-tripling in the risk of colorectal cancer compared with low intake, independent of meat, fruit, and vegetable intakes and socioeconomic indicators. Milk intake showed a similar association.2
1. Norat T, Dossus L,Rinaldi S, et al. Diet, serum insulin-like growth factor-I and IGF-binding protein-3 in European women. Eur J Clin Nutr. 2007;61(1):91-98.
2. van der Pols JC, Bain C, Gunnell D, Smith GD, Frobisher C, Martin RM. Childhood dairy intake and adult cancer risk: 65-y follow-up of the Boyd Orr cohort. Am J Clin Nutr. 2007; 86(6):1722-1729.