Tel Aviv, Apr 4 (IANS): Vitamin D, which the body synthesises with the help of sunlight, has an important bearing on the functioning of our auto-immune system, says a study.

Howard Amital, professor at the Tel Aviv University's (TAU) Sackler Faculty of Medicine and Sheba Medical Centre, has discovered that the vitamin may also improve the well being of patients in intensive care.

In a six-month study, Amital and his colleagues found that patients with vitamin D deficiency lived an average of 8.9 days less than those who were found to have sufficient vitamin D. Vitamin D levels also co-related with the level of white blood cells which fight disease.

The study demonstrated that further research will only validate the efficacy of vitamin D in improving the patient's survival outcomes, the journal QJM: An International Journal of Medicine reported.

To measure the impact of vitamin D levels on the survival of critically ill patients, the researchers designed an observational study, said a university statement.

Over six months, 130 patients over 18 years of age who were admitted to an intensive care unit of a TAU-affiliated hospital and requiring mechanical ventilation, were studied. Patients who had taken vitamin D supplements prior to admittance were excluded from the study population.

Findings indicate that while patients with sufficient vitamin D survived an average of 24.2 days, those who were deemed to be deficient in vitamin D survived an average of only 15.3 days. They were also found to have a better white blood count.