Dairy consumption and risk of prediabetes and type 2 diabetes in the Fenland study

Limited observational evidence suggests that a higher intake of high-fat dairy may be associated with lower prediabetes risk, while opposite associations have been observed for low-fat milk intake. This study aimed to examine associations between baseline and changes in dairy consumption, risk of prediabetes, and glycaemic status.

7521 participants from the prospective UK Fenland study were included (mean age 48.7 ± 2.0 years, 51.9 % female). Dairy intake was measured using self-reported food frequency questionnaires. Associations with prediabetes risk and glycaemic status were analysed using Poisson regression models adjusted for social demographics, health behaviours, family history of diabetes and food group intake.

At a mean follow-up of 6.7 ± 2.0 years, 290 participants developed prediabetes (4.3 %). Most dairy products were not significantly associated with prediabetes risk. A higher baseline intake of high-fat dairy (RR_servings/day 1.20, 95%CI 1.03-1.39) and high-fat milk (RR_servings/day 1.22, 1.01-1.47) were associated with higher prediabetes risk. Conversely, low-fat milk was associated with lower prediabetes risk (RR_servings/day 0.86, 0.75-0.98). In the analyses evaluating dietary changes over time, increases in high-fat milk were inversely associated with risk of progressing from normoglycaemia to prediabetes or type 2 diabetes (RR_servings/day 0.86, 95%CI 0.75-0.99).

This population-based study showed that most dairy products are not associated with prediabetes risk or progression in glycaemic status. Positive associations of high-fat dairy, high-fat milk, and the inverse association of low-fat milk with prediabetes risk found were inconsistent with prior literature and suggestive of the need for future research on environmental, behavioural, and biological factors that explain the available evidence.