Dairy consumption and risk of cardiometabolic diseases: a prospective cohort study of the China Kadoorie Biobank.
Kakkoura MG., Wang H., Iona A., Chen Y., Kartsonaki C., Im PK., Millwood IY., Papier K., Yu C., Pei P., Sun D., Yang L., Avery D., Yang X., Yu M., Lv J., Chen J., Li L., Chen Z., Du H., China Kadoorie Biobank Collaborative Group .
BACKGROUND: Previous evidence on the associations of dairy intake with risk of cardiometabolic diseases has been inconsistent with studies showing either inverse, null or positive associations. OBJECTIVE: We aimed to assess these associations in China, where dairy consumption level is low and cardiometabolic disease patterns differ from those in the West. METHODS: The China Kadoorie Biobank is a prospective cohort study with ∼512,000 adult participants recruited from ten diverse localities in China during 2004-08. At baseline and periodic resurveys, information on the consumption frequency of major food groups was collected using a validated interviewer-administered laptop-based questionnaire. During approximately 5.4 million person-years of follow-up, 18,306 diabetes, 33,946 ischemic heart diseases (IHD, including 3888 acute myocardial infarction [MI]), 33,670 ischemic stroke (IS), 7191 intracerebral haemorrhage (ICH) cases, and 13,241 cardiovascular deaths were recorded. Cox regression was used to calculate adjusted hazard ratios (HRs) relating dairy intake to cardiometabolic diseases risk. RESULTS: At baseline, 10.7% of participants regularly consumed (i.e. ≥4 days/week) dairy products, while 70.0% reported never or rare consumption. After adjusting for potential confounders including BMI, dairy consumption was significantly and positively associated with IHD but inversely associated with risks of acute MI, ICH and cardiovascular death, with HRs for regular consumers vs non-consumers being 1.09 (95% CI: 1.06-1.12), 0.88 (0.80-0.98), 0.69 (0.62-0.76) and 0.82 (0.77-0.87), respectively, but not with diabetes and IS. These associations were largely independent of systolic blood pressure. CONCLUSIONS: In Chinese adults, higher dairy consumption was associated with lower risks of acute MI, ICH and cardiovascular death. Future studies are warranted to further elucidate these relationships and their causality.