Vitamin D: The Secret Weapon in Fighting Influenza

Studies have shown that deficiencies in Vitamin D have a direct effect on the immune system. Learn what medical professionals are saying about vitamin D and how it can dramatically benefit your immune system.

Studies have shown that deficiencies in Vitamin D have a direct effect on the immune system.  Your body’s vitamin D levels are at their lowest levels during winter time and the end result is a lowered immune system and increase in colds and flu.

If you can imagine that your body is a plant.  A plant needs sunlight to create the photosynthesis process to thrive.  Without the sunlight, the plant withers and dies.  Our bodies are much the same.  They need certain things to thrive, and Vitamin D is one of them.  Dr. John Cannell MD, states that our Vitamin D levels are 1/3 of what they are in the summertime.

“All of epidemiology will be changed by this…  The effect vitamin D has in preventing influenza and the common cold should not be over estimated.  Especially with pandemic influenza.”


 According to the Office of Dietary Supplements, to get more Vitamin D in our diets, the U.S. government created a  fortification program to provide more sources of Vitamin D.   Foods such as milk, orange juice and breakfast cereals were among those fortified, but it still is not enough for the human body to use to combat immune attackers.
Selected Food Sources of Vitamin D 

Food IUs per serving* Percent DV**
Cod liver oil, 1 tablespoon 1,360 340
Mushrooms, enriched with vitamin D, 3 ounces 400 100
Salmon, cooked, 3.5 ounces 360 90
Mackerel, cooked, 3.5 ounces 345 86
Sardines, canned in oil, drained, 1.75 ounces 250 63
Tuna fish, canned in oil, 3 ounces 200 50
Orange juice fortified with vitamin D, 1 cup (check product labels, as amount of added vitamin D varies) 142 36
Milk, nonfat, reduced fat, and whole, vitamin D-fortified, 1 cup 98 25
Yogurt, fortified with 20% of the DV for vitamin D, 6 ounces (more heavily fortified yogurts provide more of the DV) 80 20
Margarine, fortified, 1 tablespoon 60 15
Ready-to-eat cereal, fortified with 10% of the DV for vitamin D, 0.75-1 cup (more heavily fortified cereals might provide more of the DV) 40 10
Egg, 1 whole (vitamin D is found in yolk) 20 5
Liver, beef, cooked, 3.5 ounces 15 4
12 3

They also go on to mention that if you take Vitamin D at high amounts for a longer period of time, “toxicity can occur and cause symptoms such as: nausea, vomiting, poor appetite, constipation, weakness and weight loss.  More seriously, it can also raise blood levels of calcium, causing mental status changes such as confusion and heart rhythm abnormalities.”


However, studies were shown stating that “excessive sun exposure does not result in vitamin D toxicity because the sustained heat on the skin is thought to photodegrade previtamin D3 and vitamin D3 as it is formed.   High intakes of dietary vitamin D are very unlikely to result in toxicity unless large amounts of cod liver oil are consumed; toxicity is more likely to occur from high intakes of supplements.”

This article was originally published at Ready Nutrition™ on September 17th, 2009