Usual intake of dairy products and the chance of pre-diabetes regression to normal glycemia or progression to type 2 diabetes: a 9-year follow-up

BACKGROUND: We assessed the possible effect of usual dairy consumption on pre-diabetes (Pre-DM) remission or progression to type 2 diabetes (T2D). METHODS: Pre-DM adults (n = 334; mean age 49.4 years; 51.5% men) from the Tehran Lipid and Glucose Study had baseline dairy intakes assessed in 2006–2008 and were followed up to 9 years for incident T2D or normal glycemia (NG). Biochemical measurements were performed at baseline and every 3 years. Multinomial regression models adjusted for confounders estimated odds ratios (OR) and 95% confidence intervals (CI) of incident T2D and NG per serving/day of dairy. RESULTS: Odds of NG increased by 69% per 200 g/day higher high-fat dairy intake (OR = 1.69, 95% CI 1.00–2.86, P = 0.05) while total or low-fat dairy were not related to outcomes. Higher yogurt intake was associated with increased odds of NG (OR = 1.82, 95% CI 1.20–2.74, P = 0.01). Milk, cheese, and cream-butter intakes were not associated with Pre-DM remission or progression to T2D after full adjustment. CONCLUSION: Regular dairy consumption—particularly high-fat dairy and yogurt—may increase the chance of Pre-DM regression to NG.