The Correlation between Vitamin D Status and Glycosylated Hemoglobin Levels


  • Dilgeer A. Jaf Department of Laboratory, College of Health and Medical Technology, Sulaimania Polytechnic University
  • Nadir Mustafa Qadir Nanakali Department of Biology, College of education, Salahaddin University-Erbil, Iraq
  • Khabat A. ALI Department of Biology, College of education, Salahaddin University-Erbil, Iraq


Vitamin D, HbA1c levels, ANOVA analysis, normoglycemic, prediabetic


Background: The intricate relationship between Vitamin D levels and glycemic control in
individuals with varying HbA1c levels has been a topic of significant research interest due to its
potential implications for diabetes management. This study aimed to explore the association
between Vitamin D classifications and HbA1c levels across different glycemic states and genders.
Using ANOVA analysis, we examined HbA1c levels across four Vitamin D classification groups
(Vit D 1, Vit D 2, Vit D 3, Vit D 4). Pairwise comparisons were conducted, and glycemic situations
(normoglycemic, prediabetic, and diabetic) were analyzed across these Vitamin D groups. Simple
linear regression analysis was employed to assess the correlation between Vitamin D and HbA1c
levels. Gender-based differences were also explored within each Vitamin D and HbA1c
The ANOVA analysis revealed significant differences in HbA1c levels across Vitamin D groups (p
< 0.05). Pairwise comparisons indicated substantial variations between several groups. While a
weak correlation was found between Vitamin D and HbA1c levels (R Square = 0.044), subsequent
gender-specific analysis showed no significant differences within each Vitamin D and HbA1c
The results highlight the impact of Vitamin D classifications on glycemic control, emphasizing the
importance of adequate Vitamin D levels in diabetes management. The weak correlation suggests
that while there is a connection between Vitamin D and HbA1c, other factors likely contribute to
glycemic fluctuations. Gender, however, does not seem to influence this relationship significantly,
ensuring the consistency of findings across both male and female participants.
Conclusion: This study underscores the intricate interplay between Vitamin D, HbA1c levels, and
glycemic situations. While Vitamin D exerts a subtle influence on glycemic control, its impact is
modulated by various factors yet to be explored fully. Understanding these complexities is vital for
developing personalized strategies in diabetes care


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