In April 2005, an influenza epidemic started sweeping through the maximum-security hospital for the criminally insane where Dr. John Cannell worked.
As the epidemic progressed, he noticed something unusual: although wards all around his became infected, no patients on his ward became ill, despite intermingling of both patients and nurses.
The only difference was that all of the patients on Dr. Cannell's ward had been taking 2,000 units of vitamin D every day for several months or longer.
Shortly after the epidemic, a paper in the journal Nature showed that vitamin D was a potent antibiotic, working by increasing the body's production of proteins called antimicrobial peptides. Antimicrobial peptides destroy the cell walls of bacteria, fungi, and viruses, including the influenza virus.
Dr. Cannell posits that this explains such matters as:
- Why the flu predictably occurs in the months following the winter solstice, when vitamin D levels are at their lowest
- Why influenza is more common in the tropics during the rainy season
- Why children exposed to sunlight are less likely to get colds
- Why cod liver oil (which contains vitamin D) reduces the incidence of viral respiratory infections
- Why the elderly who live in countries with high vitamin D consumption, like Norway, are less likely to die in the winter
Epidemic influenza kills roughly a million people every year worldwide, usually by causing pneumonia.
Yes indeed, vitamin D is the hidden nutrient that can help prevent and treat the flu.
This interesting article written by noted vitamin D expert Dr. John Cannell describes just how effectively the sunshine vitamin beats the flu. Dr. Cannell's results at the ward of the maximum-security hospital led him to collaborate with other noted experts -- Harvard's Dr. Edward Giovannucci and Dr. Michael Holick of Boston University -- on a more extensive paper that connects the absence of vitamin D to disease.
Just be careful to recognize that the best way to get vitamin D is NOT from pills or capsules but from sun exposure. Unfortunately, that is a major challenge in the winter for most that live in the United States.
That is also one of the primary reasons why people come down with the flu in the first place. They just don't have access to regular doses of healthy sun exposure. Fortunately, there are some good safe sun lamps that one can use in the winter.
Vitamin D has positive effects not just on influenza, but also on:
... and many other illnesses as well.
Exposure to sunlight is an important source of vitamin D. Ultraviolet (UV) rays from sunlight trigger vitamin D synthesis in the skin. Getting optimum sunlight may not be possible for everyone, however, and Dr. Cannell's article also discusses supplementation.
But supplementation is a tricky thing because you run the serious risk of overdosing if you stay on a vitamin D supplement for any length of time. It's impossible to overdose on vitamin D obtained from sun exposure, as any excess is destroyed by that process.
If you don't live in a part of the world where you can get the optimal amount of vitamin D through year-round sun exposure, I strongly recommend taking a high-quality cod liver oil and monitoring your blood levels carefully during the winter.