Milk: Cancer in a cup

Childhood dairy intake and adult cancer risk: 65-y follow-up

Background: Dairy consumption affects biological pathways associated with
carcinogenesis. Evidence for a link between cancer risk and dairy consumption in adulthood is increasing, but associations with childhood dairy consumption have not been studied adequately.

Objective: We investigated whether dairy consumption in childhood is
associated with cancer incidence and mortality in adulthood.

Design: From 1937 through 1939, some 4999 children living in England and
Scotland participated in a study of family food consumption, assessed from household food inventories. The National Health Service central register was used to ascertain cancer registrations and deaths between 1948 and 2005 in the 4383 traced cohort members. Per capita household intake estimates for dairy products and calcium were used as proxy for individual intake.

Results: During the follow-up period, 770 cancer registrations or cancer
deaths occurred. High childhood total dairy intake was associated with a
near-tripling in the odds of colorectal cancer compared with low intake,
independent of meat, fruit, and vegetable intakes and socioeconomic indicators. Milk intake showed a similar association with colorectal cancer risk. High milk intake was weakly inversely associated with prostate cancer risk.

Childhood dairy intake was not associated with breast and stomach
cancer risk; a positive association with lung cancer risk was confounded by
smoking behavior during adulthood.

Conclusions: A family diet rich in dairy products during childhood is
associated with a greater risk of colorectal cancer in adulthood. Confirmation of possible underlying biological mechanisms is needed.

From the Longitudinal Studies Unit, Division of Epidemiology and Social
Medicine, School of Population Health, University of Queensland, Brisbane,
Australia (JCvdP and CB); the Department of Social Medicine, University of
Bristol, Bristol, United Kingdom (DG, GDS, and RMM); and the Department of Public Health and Epidemiology, The University of Birmingham, Birmingham, United Kingdom (CF)