Home | Avoiding Illness | Other_Diseases | Vitamin D as effective as vaccine in preventing flu

Vitamin D as effective as vaccine in preventing flu

Font size: Decrease font Enlarge font

Taking high doses of vitamin D3 supplements in winter helps reduce risk of acquiring seasonal flu in winter, a new Japanese trial demonstrated.

The trial results, reported in the March 10, 2010 issue of American Journal of Clinical Nutrition, show that children given vitamin D(3) supplement were 42 percent less likely to get infected with seasonal flu than those who were given a placebo.

The efficacy is remarkable as it may be comparable to that of flu vaccine, which is generally low because the virus used to construct the vaccine is likely different from the circulating one.

Deficiency of Vitamin D, which is synthesized after human skin is exposed to sunlight or UV rays, has been associated with increased risk of seasonal flu and swine flu as well.  However, most of such studies were epidemiological or observational.

In the randomized, double-blind, placebo-controlled trial, Dr. Mitsuyoshi Urashima and colleagues at Division of Molecular Epidemiology Jikei University School of Medicine Minato-ku in Tokyo Japan gave one group of schoolchildren 1,200 international units per day of vitamin D(3) and another group a placebo to see how vitamin D would prevent seasonal flu.

The primary outcome of the trial was the incidence of influenza A and diagnosis was established by testing a flu antigen in a nasopharyngeal swab specimen.

During the trial between Dec 2008 and March 2009, 18 of 167 (10.8%) children given vitamin D tested positive for flu infection compared to 31 of 167 (18.6) children in the placebo group.  The relative risk is 0.58, meaning those taking vitamin D were at 42 percent reduced risk of seasonal flu.

The anti-flu effect was found much more significant among children who had not been taking other vitamin D supplements and who started nursery school after age 3.  The reduction in the risk was 64 percent for both groups.

In a subgroup of children who were previously diagnosed with asthma, 2 children taking vitamin D supplements experienced asthma attacks while 12 children receiving placebo suffered asthma attacks - meaning that vitamin D cut the risk by 83 percent.

The researchers concluded that the results suggest that vitamin D3 supplementation during the winter time may reduce the incidence of influenza A.

Dr. John Cannell, one of most knowledgeable vitamin D experts in the world and director of Vitamin D Council, a non-profit organization, and colleagues earlier published a heavy-weight review article in a scientific journal called Virology explaining that vitamin D is needed for the production of antibacterial peptides which help prevent flu. 

In winter, people tend to stay indoors.  Those who lack exposure to sunshine are prone to becoming vitamin D deficient. This is why people in winter are at higher risk of influenza including seasonal flu.

Dr. Cannell suggests adults can take 5,000 IU per day and try to maintain a blood level of 50 to 80 ng/mL (or 125 to 200 nm/L) year-round.  One early study suggests that it is safe for schoolchildren to take 2,000 IU per day for a year without any noticeable side effects.

Vitamin D is found only in a few foods including eggs and fatty fish like salmon.  Because of this, the vitamin D is fortified in some foods like milk, orange juice and cereals.  But vitamin D levels in such foods are fairly low and you may have to drink literally 20 glasses of milk to get enough vitamin D.  Vitamin D supplements are a good source of the nutrient even though sunshine is the best.

Dr. Cannell cautions that high intake of vitamin A can reduce the efficacy of vitamin D.  Cod liver oil, high in vitamin A while relatively low in vitamin D, is not as good as it used to be as a vitamin D source.

A health observer suggests that regardless of your vaccination status, an adequate level of serum vitamin D should be maintained to prevent flu and many other serious diseases like cancer, heart disease and diabetes..

For more detailed information on vitamin D, visit Vitamin D Council.

By David Liu and editing by Denise Reynolds

(Send your news to foodconsumer.org@gmail.com, Foodconsumer.org is part of the Infoplus.com ™ news and information network)

Subscribe to comments feed Comments (4 posted):

Ted Hutchinson on 03/14/2010 21:13:27
avatar
Because it usually takes 3 months to replete vitamin D status the length of this trial was too short to really demonstrate the power of vitamin d to activate the immune system. Similarly we should understand human skin makes 10,000iu given 20minutes full body sun exposure. From one month old about 100iu per 2.5lbs weight is used. 1200iu/daily is an adequate daily intake for a child weighing 30lbs only.
What we need to see is an intake of vitamin D3 that enables humans to STORE vitamin D3 in tissue. Vitamin D storage begins above 44ng/ml but to guarantee areasonable amount of vitamin d3 reserves requires a 25(OH)D level around 60ng/ml. 150nmol/l.
In the same way you can survive a financial crisis better if you have a reserve store of cash instantly at hand so your body will be able to deal with pathogens more effectively if it has a constant reserve of STRORED D3 to draw on if and as when required.
Grassrootshealth D Action offer postal 25(OH)D testing at cost price.
Thumbs Up Thumbs Down
0
Pete on 03/14/2010 21:39:45
avatar
The paper indicates that supplementation started at the start of December. The incidence of influenza showed no difference (with vitamin d intake) in the first period, significant effect in the second period and no effect in the third. The dose of vitamin d given appears to slow the decline in vitamin d levels but is insufficient to get through the winter. Thus indicating that even with children a higher dose is required. What a pity they did not measure the vitamin d levels.
Thumbs Up Thumbs Down
0
Smart Lipo on 04/15/2010 09:45:18
avatar
The reduction in the risk was 64 percent for both groups.The primary outcome of the trial was the incidence of influenza A and diagnosis was established by testing a flu antigen in a nasopharyngeal swab specimen.
Thumbs Up Thumbs Down
0
fake louis vuitton on 10/29/2010 06:07:56
avatar
month old about 100iu per 2.5lbs weight is used. 1200iu/daily is an adequate daily intake for a child weighing 30lbs only.
What we need to see is an intake of vitamin D3 that enables humans to STORE vitamin D3 in tissue. Vitamin D storage begins above 44ng/ml but to guarantee areasonable amount of vitamin d3 reserves requires a 25(OH)D level around 60ng/ml. 150nmol/l.
In the same way you can survive a finan
Thumbs Up Thumbs Down
0

Post your comment comment

Please enter the code you see in the image:

  • email Email to a friend
  • print Print version
Newsletter
Email:
Rate this article
5.00