Importance of vitamin d for immune system

Importance of vitamin D for your immune system

All the news about the recent flu pandemic has many people concerned about how vulnerable they are to CoVid-19 and similar viruses that may come up in the future. We live in the era of a global economy and are connected in countless ways to countries across the globe. One of the downsides of this fact is that it allows for illnesses to spread quickly around the world as hundreds of thousands of people travel every day. 

Father washing hands with son

How do you protect yourself from falling prey to one of these “traveling viruses?” Strictly following the CDC health recommendations1 is a good start. Wash your hands often, manage stress, get your vaccinations, don’t smoke, stay active, eat a healthy diet . . . these are all things you can do to help your immune system stay strong enough to fight off illness.

Another lesser known but equally important recommendation is getting the RDA of vitamin D. A paper published in the British Journal of Medicine2 reviewed 25 separate studies that looked at the relationship between vitamin D and the body’s ability to withstand respiratory viruses, like the Coronavirus. “The results show that taking a moderate dose of vitamin D daily or weekly (but not more irregular, large doses) helps to protect users from respiratory infections.”3

A strong immune system depends on vitamin D

Up until the past decade or so, the primary role of vitamin D was thought to be that of supporting strong bones. Vitamin D enhances intestinal calcium and phosphorus absorption, ensuring that those vital minerals are deposited in your bones and teeth. New evidence is emerging, however, about the numerous additional key ways that vitamin D supports human health. 

“Muscles need it to move, for example, nerves need it to carry messages between the brain and every body part, and the immune system needs vitamin D to fight off invading bacteria and viruses.”4 In order for your body to successfully withstand these seasonal viruses and other illnesses that travel from person to person, you must maintain a healthy level of vitamin D in your system.

Be proactive, not reactive

Various companies advertise OTC medications that claim to assist in reducing the severity and length of an illness, but the healthier option is to not contract the bug in the first place. The time to shore up your immune system is not when you get sick. Start now by taking good care of your health, and that includes getting a routine screening of your vitamin D levels, because you may be surprised to find out you’re deficient. 

Vitamin D is particularly difficult to get a sufficient amount of without supplementation. Your body makes it naturally through a chemical process that occurs when UVB sun rays come into contact with bare skin. The great majority of us, however, are not getting enough sun exposure for this method to be successful.

There are also some dietary sources of vitamin D, but it is difficult to reach the RDA through food alone. The result? “Vitamin D deficiency is considered to be one of the most common medical conditions worldwide.”5 There are healthy supplements available that can help resolve this problem.

Viruses are an inescapable reality, and the best defense you have is a healthy immune system. Help your immune system stay strong by following a healthy lifestyle and making sure you’re getting enough vitamin D.

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Healthy Living, CDC (Centers for Disease Control and Prevention). 
Vitamin D supplementation to prevent acute respiratory tract infections: systematic review and meta-analysis of individual participant data, British Journal of Medicine. 
The vitamin D factor, World.wng.org. 
Vitamin D, Ods.od.nih.gov.  
5 Prevalence of Vitamin D Deficiency among Adult Population of Isfahan City, Iran, Ncbi.nlm.nih.gov. 

NOTE: The CDC and BMJ have not reviewed or approved the above article.