Habitual Intake of Dietary Dicarbonyls is Associated with Greater Insulin Sensitivity and Lower Prevalence of Type 2 Diabetes: The Maastricht Study.

BACKGROUND

Dicarbonyls are reactive precursors of advanced glycation end-products (AGEs). Dicarbonyls are formed endogenously, but also during food processing. Circulating dicarbonyls are positively associated with insulin resistance and type 2 diabetes, but the consequences of dietary dicarbonyls are unknown.

OBJECTIVES

We aimed to examine the associations of dietary intake of dicarbonyls with insulin sensitivity, β-cell function, and the prevalence of prediabetes or type 2 diabetes.

METHODS

In 6282 participants (aged 60 ± 9 y; 50% men, 23% type 2 diabetes [oversampled]) of the population-based cohort the Maastricht Study, we estimated the habitual intake of the dicarbonyls methylglyoxal (MGO), glyoxal (GO), and 3-deoxyglucosone (3-DG) using food frequency questionnaires. Insulin sensitivity (n = 2390), β-cell function (n = 2336), and glucose metabolism status (n = 6282) were measured by a 7-point oral glucose tolerance test. Insulin sensitivity was assessed as the Matsuda index. Additionally, insulin sensitivity was measured as HOMA2-IR (n = 2611). β-cell function was assessed as the C-peptidogenic index, overall insulin secretion, glucose sensitivity, potentiation factor, and rate sensitivity. Cross-sectional associations of dietary dicarbonyls with these outcomes were investigated using linear or logistic regression adjusting for age, sex, cardiometabolic risk factors, lifestyle, and dietary factors.

RESULTS

Higher dietary MGO and 3-DG intakes were associated with greater insulin sensitivity after full adjustment, indicated by both a higher Matsuda index (MGO: Std. β [95% CI] = 0.08 [0.04, 0.12]; 3-DG: 0.09 [0.05, 0.13]) and a lower HOMA2-IR (MGO: Std. β = -0.05 [-0.09, -0.01]; 3-DG: -0.04 [-0.08, -0.01]). Moreover, higher MGO and 3-DG intakes were associated with a lower prevalence of newly diagnosed type 2 diabetes (OR [95% CI] = 0.78 [0.65, 0.93] and 0.81 [0.66, 0.99]). There were no consistent associations of MGO, GO, and 3-DG intakes with β-cell function.

CONCLUSION

Higher habitual consumption of the dicarbonyls MGO and 3-DG was associated with better insulin sensitivity and lower prevalence of type 2 diabetes, after excluding individuals with known diabetes. These novel observations warrant further exploration in prospective cohorts and intervention studies.