January 5, 2010
Bill Faloon, Co-founder of Life Extension Foundation, recently summarized some of the science showing the critical role of Vitamin D. An excerpt from his article in the January 2010 Life Extension Magazine follows:
As daylight hours grow colder and shorter, incidences of the common cold, flu, and respiratory infections spike upwards. Scientists have identified reduced vitamin D levels in winter months as a prime suspect for this increase in infectious disease cases.
Vitamin D in all forms (sunlight, sun lamps, or supplements) reduces the incidence of respiratory infections.[24,26] Dutch children with the least sun exposure are twice as likely to develop a cough and three times more likely to develop a runny nose compared with children with the most sun exposure.
When Russian athletes were given access to a sun lamp to stimulate vitamin D synthesis in the body, there were 50% fewer respiratory infections and 300% fewer days of absence.
Children with the lowest vitamin D serum levels are 11 times more likely to develop respiratory infection. When 60,000 IU per week of vitamin D was administered (for six weeks) to children with frequent respiratory infections, the result was a complete disappearance of such infections in the following six months.
In a controlled trial of African women, a low dose (800 IU a day) of vitamin D resulted in a 3-fold reduction in cold and flu symptoms compared to those given placebo.
Influenza kills between around 36,000 Americans each year. Ensuring optimal vitamin D status could slash influenza incidence and morality.
Flu viruses (including swine flu) induce a massive inflammatory response that can kill the victim. In other words, it is not the virus that often kills, but the body’s hyper-reaction to the virus—in the form of uncontrolled over-production of pro-inflammatory cytokines.
Vitamin D down-regulates the expression of pro-inflammatory cytokines such as tumor necrosis factor-alpha. 
As people age, they often over-express these same destructive pro-inflammatory cytokines. The result is chronic low-level inflammation that damages aging arteries, joints, and neurons[40-44]. By down-regulating excess pro-inflammatory cytokine production, vitamin D could save the lives of those stricken with acute influenza, or the dozens of inflammatory diseases that afflict millions of aging Americans each year.
Natural News provides links to more than 200 featured Vitamin D articles.
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