How Does the Sun Help Make Vitamin D3?


Natural Vitamin D3 production begins with the synthesis of a protein present throughout your skin.

The Sun’s ultraviolet B (UVB) rays interact with this protein converting it into a D vitamin called preD3 after which it is finally converted into the vitamin D3 our body is able to use.

An Essential Essential Vitamin In More Ways than One

Vitamin D3 is crucial to the maintenance of normal blood levels of calcium and phosphorus which help develop and strengthen bones.

D3 aids the development of teeth and it is thought that supplements can reduce the number of non-spinal fractures.

Vitamin D3 The Sunshine Vitamin
Vitamin D3 the sunshine vitamin.

Many people do not get enough of this vital vitamin because it is unable to make the sufficient amounts needed to sustain a healthy immune system especially if you live in northern climates or do not spend much time in the Sun.

Your body uses sunlight to make Vitamin D3 naturally therefore not having access to sunshine all year round or not spending enough time out in the Sun means you will already have a significant shortfall in your vitamin D stores.

Vitamin D Deficiency & Chronic Illnesses

In the absence of very low vitamin D3 store can lead to a variety of ailments, most visually and notably are the bent limbs and weak bones characteristic of Rickets.

Rickets is a rare disease that causes the bones to become soft and bend, children, especially children of color are at higher risk of getting Rickets.

In adults, severe vitamin D deficiency leads to Osteomalacia a disease which causes weak bones, bone pain, and muscle weakness.

Vitamin D3 is one of the most essential vitamins we need and is most likely the one we are most deficient in.


Researchers are studying vitamin D for its possible connections to several medical conditions, including diabetes, high blood pressure, cancer, and autoimmune conditions such as multiple sclerosis.

They need to do more research before they can fully understand the effects of vitamin D on these conditions.

How Exactly Does this Process Take Place?

The process was first detailed in a 1980 study by M. F. Holick and colleagues that used rat skin as a model for human skin.

Vitamin D synthesis begins with a cholesterol (7-DHC), a protein present throughout the skin but most highly concentrated in the lowest layers of the epidermis.

The Sun’s ultraviolet B radiation penetrates through the skin converting the 7-DHC into an isomer which is the same chemical formula as D3, but different, called preD3.

Sunshine & Vitamin D3
Vitamin D3 and C make up the two sunshine Vitamins.

The final stage, isomerization, converts the pre D3 into vitamin D3 which is dependent on the temperature within the skin.

To keep the reaction going, a protein descriptively named vitamin D binding protein binds to the newly created vitamin D3 and transports it into the blood via capillaries located where the epidermis meets the lower skin layer of the dermis.

Vitamin D binding protein ensures that synthesis proceeds as efficiently and as efficiently as possible and with temperatures at or near body temperature the reaction can proceed for around three days, continuing even after sun exposure ends.

Does Skin Color Have An Impact on the Ability to Produce Vitamin D3 this Way?

Yes, it does.

The biggest drawback being skin tone, skin tone which is usually darker in hotter climates contain a pigment called Melanin which gives skin its beautiful color.

Melanin absorbs the suns ultra violet rays that initiate vitamin D synthesis significantly inhibits the skins’ ability to produce levels of Vitamin D3.

This in itself makes it almost impossible for people with skin tones ranging from very light brown to very dark black skin are unable to produce enough D3 from synthesis.

However, skin color or the lack of Melanin in your skin bears no significance in countries that can go without sunshine for up to six months a year.

So if you live in the Northern Hemisphere where the days are shorter and the nights longer in winter, it will be literally impossible for you or anyone else for that matter to produce enough vitamin D3 naturally through sunlight alone.

A Word of Warning

Sunscreen can also inhibit the process of synthesis in your skin because it blocks both the ultraviolet A (UVA) rays and ultraviolet B (UVB) rays from the sun.

However, wearing sunscreen is a must and should be used at all times whenever in the Sun to help protect your skin from any form of Sun damage.

You need sunscreen just as much as you need vitamin D3
Wearing sunscreen is a must and should be used at all times whenever in the Sun.

Best Food Source

The only plant source that is able to produce Vitamin D3 are mushrooms, only if they have been grown under UV lights to mimic those of the Sun.

I personally ensure I include as much fresh meat, vegetables and fruit in my family’s diet as possible, always have.

I’ve always drank lots of milk too, love the stuff, however these factors did not prevent me from having a vitamin D3 deficiency and low calcium levels.

The following link is the  D3 supplement I currently take and have done so for the past year.

The idea is that supplements work in harmony with your main diet not replace it.

Fatty fish, sea food, egg yolk, cheese, pork chops, cod liver oil, fortified margarine and yogurts are all fantastic sources of vitamin D3.

Food rich In vitamin D3
Supplements are meant to complement your diet not replace it.

Please feel free to leave any advice, thoughts or comments in the space provided for you, they are always encouraged and always very much appreciated.

Stay Save, Stay Healthy, Stay Strong

About Mitch--founder-of-immune-system-explained-in-bermuda

Mitch X:-).

*Please note the information contained in this post is intended for the purpose of general information and should not be used as a substitute for the individual expertise and judgment of healthcare professionals.

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