Abstract
BACKGROUND: The impact of milk consumption on cardiovascular disease (CVD) risk or mortality is unclear, and specific comparisons between types of milk are scarce. OBJECTIVES: We aimed to investigate the associations between milk consumption, measured in a large Norwegian cohort in 3 counties during 1974-1988, and CVD-related mortality and all-cause mortality and to compare the associations between whole (full-fat) and low-fat milk. METHODS: This population-based, prospective cohort study included adults invited to repeated health screenings in the Norwegian Counties Study (>80% attendance). Dietary intake was assessed from food frequency questionnaires at each screening in 1974-1988. Cox regression analysis was used to estimate hazard ratios (HRs) with 95% CIs for the associations between milk intake (assessed as cumulative mean intake from repeated questionnaires) and risk of death from all CVD, ischemic heart disease (IHD), acute myocardial infarction (AMI), and all causes. RESULTS: Among 73,860 participants included in this study (mean age: 41.2 years at baseline; 49% females), 26,393 deaths occurred (8590 from CVD, 4372 from IHD, and 3047 from AMI) during a median follow-up of 33 y. Comparing the highest with the lowest quintile of overall milk intake, the HR was 1.12 (95% CI: 1.03, 1.21) for CVD-related mortality and 1.22 (95% CI: 1.16, 1.28) for all-cause mortality. For whole milk, high compared with no intake was positively associated with CVD (HR: 1.07; 95% CI: 0.99, 1.16), IHD (HR: 1.13; 95% CI: 1.01, 1.27), and all-cause mortality (HR: 1.15; 95% CI: 1.10, 1.21). Compared with whole milk, low-fat milk intake was associated with lower CVD-related, IHD-related, AMI-related, and all-cause mortality. The associations were attenuated in analyses considering only baseline intakes. CONCLUSIONS: In this cohort with high milk consumption, whole milk is associated with higher CVD and all-cause mortality, whereas low-fat milk is not. Low-fat milk may be associated with lower risks than whole milk.