Between 1987 and the date of the present issue, 10 reports have been published on the prevalence of the vitamin D deficit in Argentina. These studies were done investigating new born babies, children, adolescents, and healthy and institutionalized adults, living in southern, middle or northern cities of Argentina. The weighed prevalence of vitamin D deficit in those reports was 43.3% (436/1007). This figure may be lower than reality because it is not known whether the stratification (age and location of residence) of the sum of samples agree with that of the national population. Taking into account the obvious difficulties in carrying out such a research two areas for further research are suggested: a) an investigation on the solar exposure in summer needed to obviate (or not) the oral supplementation of vitamin D in winter, b) to determine the success of the schema of administration taking into account the current controversy between dose and optimum plasma levels of 25(HO)D3. In both instances, the end point should include some of the physiological functions alluded to in this editorial.