Research Article Dairy Intakes inOlderGirls andRisk of BenignBreastDisease in Young Women

Previous investigations found high dairy intakes in girls associated with rapid height growth and excess weight gain, which had opposite relationshipswith benign breast disease (BBD) in youngwomen.We use data fromthe longitudinalGrowingUpTodayStudy (GUTS) to investigatewhetherdairy intakes, in older children/ adolescents, are associated with BBD risk in young women. GUTS includes 9,039 females, ages 9–15 years in 1996, who completed questionnaires annually through 2001, then in 2003, 2005, 2007, and 2010. Dietary food frequencies (1996–2001) obtainedmilk, yogurt, and cheese intakes. On 2005–2010 surveys, 7,011 females (18–29 years) reported whether a health care provider ever diagnosed them with BBD (n 250) and if confirmed by breast biopsy (n 105). Logistic regressionmodels estimatedassociations betweenprevalent biopsy-confirmed BBD and dairy intakes, adjusted for age and energy. Multivariable-adjusted models additionally included menarche age, childhood adiposity, adolescent alcohol consumption, and pregnancy. Further analyses stratified by family history. Age-energy–adjusted models of dairy (milk, yogurt, cheese, total dairy servings, dairy protein, dairy fat) intakes at 14 yr found no significant associations with BBD risk [milk: OR, 0.90/ (serving/d); 95 % confidence interval (CI), 0.76–1.05; dairy protein: OR, 0.98/(10 g/d); 95 % CI, 0.82–1.17). Separate analyses of dairy intakes at 10 yr, intakes before the growth spurt, during the growth spurt, before menses-onset, and after menses-onset provided no significant associations with BBD. Multivariable adjust-ment, and family history stratification, did not alter the above findings.We conclude that dairy intakes by older girls haveno strong relationwithBBDrisk in youngwomen. Becauseof small number of cases, it is important to continue follow-up and re-examine later. Cancer Epidemiol Biomarkers Prev; 22(4); 1–5. 2013 AACR