The master's thesis at the College of Pharmacy at the University of Basrah examined (the relationship between calcium and vitamin D levels with insulin resistance and beta-cell disruption in susceptible individuals and type 2 diabetes patients) by Zaman Rashid Hashem.
  The thesis dealt with (150) participants who were divided into three groups of patients with type 2 diabetes, susceptible and healthy people. Each group included (50) participants in order to measure insulin resistance and the function of pancreatic beta cells by measuring fasting glucose, cumulative sugar, and insulin levels, in addition to other measurements.  Recommended Vitamin D and Calcium
 The thesis concluded the negative relationship between vitamin D in both fasting and cumulative sugar levels, as well as the negative relationship between vitamin D and insulin resistance. On the other hand, the study showed a positive relationship between calcium with fasting sugar and cumulative sugar. Therefore, vitamin deficiency may significantly affect blood sugar regulation as well as  Any imbalance of calcium, such as increased calcium levels, may be a risk factor for developing type 2 diabetes.