Diabetes is a type of disease that affects the rest of the body's functions. The study was conducted at Al-Ramadi Teaching Hospital for Women and Children for the period from 2021-2022. Our study aimed to investigate the relationship between the three types of diabetes (T2DM, gestational diabetes and T1DM). The study found that age affects disease severity levels in addition to weight, where the effect was less in type 2 and gestational diabetes. For fats, there was no strong effect in increasing diabetes. With regard to low-density lipids, it has been shown that it directly affects the development of the disease, because triglyceride levels have a strong and direct influence on the development of diabetes, especially type 1 and type 2. Cumulative glucose testing: Sugar and insulin have been linked to disease. In this study, when performing Pearson's correlation analysis of the relationship between TSH and some biochemical tests, there was a strong correlation between TSH, age, weight, T3, RBS, HbA1c and insulin, while there was no correlation for TSH with lipids, T4 and other tests. These results indicate the importance of thyroid screening for diabetic patients.