Vitamin D – What Is It & Why Do We Need It?


Vitamin D is critical for bone health, but recently its importance has been extended to just about all areas of good health. 

Unfortunately, the majority of the population isn’t getting nearly enough, largely due to a lack of awareness on the importance of this vitamin.

Nicknamed the sunshine vitamin – Vitamin D is different from other essential vitamins because our own bodies can manufacture it with sunlight exposure.

Vitamin D plays a critical role in the body’s use of calcium and phosphorous.

The main function of vitamin D is to regulate the absorption of calcium and phosphorus in our bones and aid in cell to cell communication throughout the body.

It works by increasing the amount of calcium absorbed from the small intestine, helping to form and maintain bones.

It’s also an important factor in making sure your muscles, heart, lungs and brain work well and that your body can fight infection.

A deficiency is now also related to many chronic disorders including mental illness, heart disease, infection, autoimmune diseases, cancer, rickets, obesity, inflammation, diabetes, and so on.

A recent study in a Boston hospital, found about 42% of the adolescent patients that were examined, had a deficiency and an estimated 1 billion people world-wide aren’t getting enough.

Vitamin D is a fat soluble vitamin that can come in two forms, D2 (ergocalceiferol) from plants and D3 (cholecalciferol) from animals.

While there are two forms, vitamin D3 is the only one that is naturally seen in humans.

Vitamin D can either be consumed (e.g. in egg yolks, oily fish, and fortified foods, or for vegans, mushrooms), although dietary sources are typically not sufficient, or produced by our skin following the sun’s (UV light) action on a compound called 7-dehydrocholesterol.

Both dietary and endogenous vitamin D will be converted to 25-hydroxycholecalciferol (25(OH)D3) in the liver and then to the active 1,25-dihydroxycholecalciferol (1,25 (OH)2D3) form, calcitriol, in the kidney.

This chemical Calcitriol acts as a hormone and is sent all over your body where different tissues, including your kidney, turn it into activated vitamin D.

This activated vitamin D is now ready to perform its duties. From here, it gets a little complicated, but you can think of activated vitamin D working in two ways:

  • Manages calcium in your blood, bones and gut.
  • Helps cells all over your body to communicate properly.

Vitamin D is crucial for just about all areas of health and reduces risks for many chronic diseases, fights obesity, and has even been shown to boost athletic performance.

Hopefully you now have a better understanding of the importance of vitamin D and how to get enough.

Vitamin D Supplements Reduce Pain in Fibromyalgia Sufferers – See more at:


  • Ewan says:

    Vitamin D deficiency is also associated with a greater risk of allergies, such as to pollens, since my daughter started having her vit d drops her allergies have been much better.

    • fibrogirl says:

      I wonder how old is your daughter? Im glad she is finding relief, and I hope that more people realise how important this vitamin is for everyone.

  • Joy says:

    I always get some side effects of taking vitamin D dry mouth and a metallic taste it is horrid

  • fibrogirl says:

    Thank you for your interest – Спасибо за ваш интерес

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