Is there a relationship between vitamin D and flu season? Studies show that low levels of vitamin D in winter due to low sun exposure lead to flu outbreaks.
The flu, known as influenza, is a respiratory infection caused by a virus infection of the nose, throat, and lungs. Influenza is most prevalent during the winter season and the symptoms commonly include fever, chills, sore throat, cough, body aches, and fatigue.
Vitamin D is a vital part of the immune system and in order to make it in the body, skin needs to be exposed to the sun. For darker skinned people, it could take as much as 15-20 minutes of sun exposure in order for the body to make the daily amount of vitamin D recommended.
Studies have revealed that there is a correlation between getting influenza and vitamin D levels. Influenza outbreaks occur prominently in the winter, which correlate to when vitamin D levels are severely reduced. Since influenza is seasonal, it is believed that vitamin D may be a contributing factor since it occurs in winter when skin is not exposed to the sun. Therefore, lack of vitamin D may play a significant role in increasing the sensitivity to developing influenza.
Vitamin D receptors are found on the surface of the human cell where they receive chemical signals. These chemical signals attach themselves to the receptors and facilitate an intercellular response. In the immune system specifically, there are vitamin D receptors found on cells where vitamin D can bind to its respective receptor sites.
Vitamin D in the immune system serves to reduce levels of inflammatory proteins called cytokines, as well as increase the amount of antimicrobial proteins, which are responsible for destroying invading germs and viruses. This pattern of reducing inflammation and rising antimicrobial defenses helps the immune system fight infections like the flu more efficiently.
Many studies regarding influenza have presented that people are more likely to get the flu if they have lower levels of vitamin D than those who have higher levels. Although there has not been that many studies conducted about treating the flu with vitamin D, some research has exhibited a relationship between higher levels of vitamin D and quicker duration of experiencing the flu infection.
Subsequently, certain experiments have shown that taking vitamin D supplements can diminish chances of getting the infection to begin with. Some researchers suggest consuming more vitamin D to safeguard against the flu, but more experiments are required to predict whether or not taking a vitamin D supplement can be considered a preventative for the flu for sure.
While it is thought that having high levels of Vitamin D may aid in preventing getting infected with the flu virus, further experiments are required in order to determine if consuming vitamin D supplements can avert influenza, or make the length of the virus quicker. Research has not been able to show conclusively that low vitamin D levels are a direct causation of the flu yet.
However, since skin surface is covered in the winter and the UV rays of the sun can’t reach the skin for vitamin D production, it seems logical that it could result in a weakened immune system. If you live in a cold area and your skin does not get adequate sun exposure, you may want to supplement with Vitamin D. The recommended daily amount of Vitamin D needed to boost your immune system in winter is 8000-10000 UI which can be taken as a daily supplement.