Effect of Vitamin D on Metabolic Parameters in Patients With the Metabolic Syndrome

In recent years emphasis has been given to investigate the role of vitamin D in areas beyond bone metabolism and maintenance of calcium homeostasis. Thus, vitamin D deficiency has been associated with risk factors for the occurrence of cardiovascular disease as well as with overall mortality.In addition, there are indications that a large proportion of the population (up to 50%) is vitamin D deficient. The measurement of vitamin 25 (OH) D3 levels is the best way to estimate the vitamin D actual reserves. It is worth mentioning that elevated levels of parathyroid hormone (PTH) \[5\] and reduced levels of 1,25 (OH)2 vitamin D3 (calcitriol have also been associated with cardiovascular disease. The metabolic syndrome is a sum of risk factors for cardiovascular disease and is found in approximately 25% of the Greek population.There are a lot of data linking low vitamin D levels with the metabolic syndrome as a whole as well as with its individual characteristics. Specifically, vitamin D deficiency has been associated with increased incidence of hypertension, dyslipidemia, obesity, inflammation and dysglycemia. Many studies have explored the effect of giving vitamin D supplements on the risk factors associated with the metabolic syndrome and the cardiovascular disease. The results of these studies are conflicting and this may partially be due to different doses of vitamin D used. The form of vitamin D most commonly used in these studies is cholecalciferol (vitamin D3. Aim of the study: Determination of the effect of cholecalciferol (VitD3) (2200 IU/day) on metabolic parameters in patients with metabolic syndrome. Endpoints: The primary endpoint will be changes in metabolic syndrome parameters 3 months after starting treatment: * Waist circumference * Blood pressure * Levels of fasting serum triglycerides * Levels of high-density lipoprotein cholesterol (HDL-C) * Levels of fasting serum glucose. The secondary endpoints will include changes in: * The levels of low-