Antioxidant Nutrients and Risk of Latent Autoimmune Diabetes in Adults and Type 2 Diabetes: A Swedish Case-Control Study and Mendelian Randomization Analysis

Nutrients. 2023 May 30;15(11):2546. doi: 10.3390/nu15112546.

Abstract

Antioxidant vitamins C and E are inversely associated with type 1 diabetes (T1D). We investigated if antioxidants are also associated with latent autoimmune diabetes in adults (LADA), with low (LADAlow) and high (LADAhigh) autoantibody levels, type 2 diabetes (T2D), and estimates of beta cell function (HOMA-B) and insulin resistance (HOMA-IR). We used Swedish case-control data with incident cases of LADA (n = 584) and T2D (n = 1989) and matched population-based controls (n = 2276). Odds ratios (OR) and 95% confidence intervals (CI) were calculated per one standard deviation higher beta-carotene, vitamin C, vitamin E, selenium, and zinc intakes. Two-sample Mendelian randomization (MR) analyses assessed causality between genetically predicted circulating antioxidants and LADA, T1D, and T2D, using summary statistics from genome-wide association studies. Among the antioxidants, vitamins C and E were inversely associated with LADAhigh (OR 0.84, CI 0.73, 0.98 and OR 0.80, CI 0.69, 0.94 respectively), but not with LADAlow or T2D. Vitamin E was also associated with higher HOMA-B and lower HOMA-IR. MR analyses estimated an OR of 0.50 (CI 0.20, 1.25) for the effect of vitamin E on T1D, but did not support causal relationships between antioxidants and either LADA or T2D. In conclusion, vitamin E may have a protective effect on autoimmune diabetes, possibly through preserved beta cell function and less insulin resistance.

Keywords: LADA; antioxidants; autoimmune diabetes; type 2 diabetes.

MeSH terms

  • Adult
  • Antioxidants
  • Ascorbic Acid
  • Case-Control Studies
  • Diabetes Mellitus, Type 1* / epidemiology
  • Diabetes Mellitus, Type 1* / genetics
  • Diabetes Mellitus, Type 2* / epidemiology
  • Diabetes Mellitus, Type 2* / genetics
  • Genome-Wide Association Study
  • Glucose Intolerance*
  • Humans
  • Insulin Resistance*
  • Latent Autoimmune Diabetes in Adults* / epidemiology
  • Latent Autoimmune Diabetes in Adults* / genetics
  • Mendelian Randomization Analysis
  • Nutrients
  • Sweden / epidemiology
  • Vitamin E
  • Vitamins

Substances

  • Antioxidants
  • Vitamin E
  • Vitamins
  • Ascorbic Acid