VITAMIN D TEST is intended for persons commonly at risk for vitamin D deficiency, such as people who get tired and fatigued easily, inadequate sun exposure, limited oral intake, or have impaired intestinal absorption. 
 
VITAMIN D
Vitamin D refers to a group of fat-soluble secosteroids responsible for increasing intestinal absorption of calcium, iron, magnesium, phosphate and zinc. Vitamin D is produced by skin exposed to ultraviolet B radiation or obtained from dietary sources, including supplements. Average daily vitamin D intake in the population and current dietary reference intake values are often inadequate to maintain optimal vitamin D levels. Virtually every cell in our body has receptors for Vitamin D, meaning that they all require "sufficient" level of Vitamin D for adequate functioning. 
Vitamin deficiency has been linked to various serious diseases: osteoporosis, multiple sclerosis, cardiovascular diseases, pregnancy complications, diabetes, strokes, autoimmune diseases, infectious diseases, etc. 
 
TEST PRINCIPLE
Vitamin D test is an immunochromatographic assey that thanks to specific antibodies, is  able to detect the levels of 25 - hydroxyvitamin D in the blood and to highlght its concentration thanks to the intensity of the test line (T) obtained.