Vitamin D and cardiometabolic risk factors and diseases MOUSAAYA MUHAMMAD SALAH EL-DIN MUHAMMAD 2018 This thesis examines the relationships between vitamin D and cardiometabolic risk factors and diseases and the efficacy of vitamin D supplementation in reducing cardiometabolic risk. Taken together, the research presented in this thesis suggests that vitamin D supplementation does not reduce clinical measures of cardiometabolic risk, but may have beneficial effects on inflammation in certain population groups, including in patients with type 2 diabetes, as well as in pregnant women. The work presented herein advances knowledge in the field of vitamin D research and provides a basis for future epidemiological and clinical studies in this field.