 Obesity, and its metabolic consequences - impaired fasting glucose IFG and diabetes, is highly prevalent among Arab women in Israel and the Middle East. Since life style modification is difficult to achieve in this population it is important to assess whether other modifiable risk factors can be detected. There is evidence that the homeostasis of vitamin D has a significant role in the eventual development of diabetes. Previous cross sectional studies have shown that low 25 OH vitamin D levels are related to glucose intolerance, diabetes, insulin resistance and metabolic syndrome. The study hypothesis is that 25OH vitamin D deficiency is highly prevalent among Arab women with IFG and that vitamin D supplementation may improve IFG and by that reduce the risk for future overt diabetes. Additionally, obesity is associated with a low-grade inflammation of white adipose tissue WAT resulting from chronic activation of the innate immune system. In obesity, there is an increased production and secretion of a wide range of inflammatory molecules including interleukin-10 IL-10, which may have systemic effects on WAT and other organs. To that end the investigators will assess the influence of vitamin D supplementation on IL-10 and hs-CRP. 