Nonfermented milk and other dairy products: associations with all-cause mortality

• Published in: The American journal of clinical nutrition Vol. 105; no. 6; pp. 1502 - 1511
• Main Authors: Tognon, Gianluca, Nilsson, Lena M, Shungin, Dmitry, Lissner, Lauren, Jansson, Jan-Håkan, Renström, Frida, Wennberg, Maria, Winkvist, Anna, Johansson, Ingegerd
• Format: Journal Article
• Language: English
• Published: United States American Society for Clinical Nutrition, Inc 01.06.2017; Oxford University Press
• Subjects: Adult; All-cause mortality; Animals; Body mass; Body mass index; Body size; Butter; Butter - adverse effects; Cause of Death; Cheese; Consumers; Dairy Products; Diet; Dietary Fats - adverse effects; Energy Intake; Feeding Behavior; Female; Fermentation; Fermented dairy products; Fermented milk; Fermented milk products; Hazards; Health Sciences; Humans; Hälsovetenskap; Lactase; Lactose; Lactose Intolerance - genetics; Life Style; Male; Medical and Health Sciences; Medicin och hälsovetenskap; Middle Aged; Milk; Milk - adverse effects; Mortality; Nonfermented milk; Nutrition and Dietetics; Näringslära; Original Research Communications; Physical activity; Polymorphism; Polymorphism, Single Nucleotide; Randomization; Risk Factors; Sensitivity analysis; Single-nucleotide polymorphism; Smoking; Statistical models; Sweden - epidemiology; fermented dairy products; nonfermented milk; butter; all-cause mortality; milk; dairy products; fermented milk; cheese
• ISSN: 0002-9165; 1938-3207
• DOI: 10.3945/ajcn.116.140798

A positive association between nonfermented milk intake and increased all-cause mortality was recently reported, but overall, the association between dairy intake and mortality is inconclusive. We studied associations between intake of dairy products and all-cause mortality with an emphasis on nonfermented milk and fat content. A total of 103,256 adult participants (women: 51.0%) from Northern Sweden were included (7121 deaths; mean follow-up: 13.7 y). Associations between all-cause mortality and reported intakes of nonfermented milk (total or by fat content), fermented milk, cheese, and butter were tested with the use of Cox proportional hazards models that were adjusted for age, sex, body mass index, smoking status, education, energy intake, examination year, and physical activity. To circumvent confounding, Mendelian randomization was applied in a subsample via the lactase - single nucleotide polymorphism that is associated with lactose tolerance and milk intake. High consumers of nonfermented milk (≥2.5 times/d) had a 32% increased hazard (HR: 1.32; 95% CI: 1.18, 1.48) for all-cause mortality compared with that of subjects who consumed milk ≤1 time/wk. The corresponding value for butter was 11% (HR: 1.11; 95% CI: 1.07, 1.21). All nonfermented milk-fat types were independently associated with increased HRs, but compared with full-fat milk, HRs were lower in consumers of medium- and low-fat milk. Fermented milk intake (HR: 0.90; 95% CI: 0.86, 0.94) and cheese intake (HR: 0.93; 95% CI: 0.91, 0.96) were negatively associated with mortality. Results were slightly attenuated by lifestyle adjustments but were robust in sensitivity analyses. Mortality was not significantly associated with the genotype in the smaller subsample. The amount and type of milk intake was associated with lifestyle variables. In the present Swedish cohort study, intakes of nonfermented milk and butter are associated with higher all-cause mortality, and fermented milk and cheese intakes are associated with lower all-cause mortality. Residual confounding by lifestyle cannot be excluded, and Mendelian randomization needs to be examined in a larger sample.