Vitamin D is called as "nature's antibiotic" as recent discoveries have brought to light its numerous health benefits.
Right from the health of your immune system to prevention of heart disease and even vulnerability to influenza, vitamin D is now seen as one of the most critical nutrients for overall health.
But it is also one of those most likely to be deficient - especially during winter when production of the "sunshine vitamin" almost grinds to a halt for people.
Analogs of the vitamin are even being considered for use as new therapies against tuberculosis, AIDS, and other concerns.
And federal experts are considering an increase in the recommended daily intake of the vitamin as more evidence of its value emerges, especially for the elderly.
"About 70 percent of the population of the United States has insufficient levels of vitamin D. This is a critical issue as we learn more about the many roles it may play in fighting infection, balancing your immune response, helping to address autoimmune problems, and even preventing heart disease," said Adrian Gombart, a principal investigator with the Linus Pauling Institute at Oregon State University.
Among other findings about benefits of Vitamin D is the ones made by OSU scientists that it induces the "expression" of cathelicidin, an antimicrobial peptide gene.
This explains in part how it helps serve as the first line of defense in your immune response against minor wounds, cuts, and both bacterial and viral infections.
Experts believe advances in the use of cathelicidin may form the basis for new therapies.
"Vitamin D insufficiency and deficiency is a world-wide, public health problem in both developed and developing nations. Nearly one billion people world-wide are deficient," the new report concluded.
The new report found that low levels of circulating vitamin D are associated with increased risk and mortality from cancer.
Vitamin D plays an important role in activating the immune system, fostering the "innate" immune response and controlling over-reaction of adaptive immunity, and as such may help control autoimmune diseases such as multiple sclerosis, psoriasis and rheumatoid arthritis.
The regulation of cathelicidin by vitamin D, a unique biological pathway for the function of vitamin D that could help explain its multiple roles in proper immune function, is so important that it's only known to exist in two groups of animals - humans and non-human primates - and has been conserved in them through millions of years of evolution.
Epidemiological studies show a link between vitamin D deficiency and increased rates of respiratory infection and influenza, and it has been hypothesized that flu epidemics may be the result of vitamin D deficiency.
Higher levels of a protein linked to vitamin D have been associated with reduced infections and longer survival of dialysis patients.
Vitamin D has important roles in reducing inflammation, blood pressure and helping to protect against heart disease.
The study has been published in Future Microbiology, a professional journal.