Vitamin D

It’s that time of year to start thinking even more about Vitamin D. The days are getting shorter, “cold season” is coming.  But why? Why do I need it? What is Vitamin D, and how do I get it? Here’s a breakdown of this crucial nutrient.

What is Vitamin D?

As the title suggests, you would assume Vit D is a vitamin similar to Vitamin A, B, C, etc… However, since our bodies can produce Vit D, it does not technically qualify as a vitamin. Vit D is more like a hormone like testosterone, estrogen, and cortisol. Specifically, Vit D is a precursor to an essential hormone called calcitriol. More on this later. 

Why do we need Vitamin D?

As mentioned above, Vit D helps create the crucial hormone calcitriol. This hormone is responsible for over 2,700 bonding sites with our DNA, including bonding sites relating to virtually every major human disease. This makes Vit D crucial to one’s health. Vit D is also important for bone health and many other bodily functions.

How do we get Vitamin D?

The primary source of Vit D is not food, but sunlight. When UVB light penetrates the skin, a chemical reaction produces Vit D. We can also get some Vit D from food sources, including oily fish (salmon, sardines, etc.), mushrooms, and fortified dairy products.

Who needs Vitamin D?

Everyone! Studies show that 75% of Americans are deficient in Vit D. Why is this? Here are a few reasons why:

Lack of sunlight

Getting ample exposure to sunlight is harder than it seems. Many people are indoors during peak sunlight hours, limiting their ability to obtain UVB light. Also, people with darker complexions have a harder time absorbing UVB light, hence limiting their Vit D production. Lastly, UVB light exposure only occurs during a limited window of total sunlight hours. If you’re curious about why that is, this video does a great job explaining it. In addition, there’s a great app called dminder that will calculate your optimal sun exposure hours for obtaining Vit D and track your intake.

Lack of Vitamin D in Diet

Not considering the amount of sunlight one gets, the “standard American diet” is low in Vit D. This means that most Americans do not eat enough of the foods containing Vit D to meet their daily requirement of the nutrient. Even the sources mentioned above (oily fish, eggs, mushrooms, and fortified dairy) contain minimal amounts of Vit D. To get enough of your daily Vit D from oily fish, you’d have to eat two or more large portions daily. When it comes to eating mushrooms, eggs, and fortified dairy products, let’s just say you’d have to eat copious amounts to get adequate amounts of Vit D from these foods.


Excess body fat will store Vit D, yet limits your body’s ability to utilize it.

Lack of supporting nutrients

Sulfur, boron, magnesium, and vitamin K2 all help contribute to the efficiency and efficacy of Vit D. I encourage you to look up what foods are high in each of these vitamins and minerals to see if they make it into your regular eating habits.

Should you supplement Vitamin D?

This is always a great question, and the answer is always: it depends. If you are getting enough of a nutrient through your diet or lifestyle, then you don’t need to waste your money on supplementing it. But how do you know if you’re actually getting enough? It is always good practice to get your nutrient levels tested multiple times a year to see if you are deficient in any nutrient. As always, you should consult your licensed healthcare provider before making any major changes to your diet. With that being said, supplementing Vit D is relatively easy and cheap and very difficult to take too much to cause toxicity. 

Whenever taking any supplement, it is vital to get quality supplements that are third-party tested – meaning a reputable outside company has tested their quality. Look for these logos:

Summary and Conclusion

Vitamin D is a critical nutrient that helps us stay disease-free and strengthen our bones. It’s a nutrient that most people do not get enough of. The biggest takeaway from this post should be this – get outside! At Huts for Vets, we’ll take every excuse to get outside.  We challenge you to take a hike or a walk, practice shinrin-yoku, and expose your skin to the sun as much as you can during peak UVB light hours without getting sunburnt. As always, eat a balanced diet and stay active. Please consult your licensed healthcare provider before supplementing Vit D or any nutrient. If you have any questions regarding vitamin D, nutrition, physical activity, or other health-related topics, please reach out to me at Thanks for reading, and be well!

DISCLAIMER: This blog is not medical advice. The stated information is purely informational and you should do your own research and consult your licensed healthcare provider before making any lifestyle changes.