Vitamin D 101: A Comprehensive Beginner’s Guide
Vitamin D is different from other vitamins.
Studies have shown that it is a steroid hormone produced from cholesterol after the skin is exposed to the sun.
This explains why vitamin D is often called “sunshine vitamin.”
However, exposing oneself to the sun doesn’t provide as much vitamin D, making it necessary to obtain it from your diet or supplements.
Yet, only a limited number of foods contain significant amounts of vitamin D, which is why vitamin D deficiency is widespread.
A study published in the journal Nutritional Research found that over 41.6% of the population of the United States is deficient in vitamin D.
This vitamin D 101 article explains everything you need to know about vitamin D.
Let’s get started!
What is vitamin D?
Vitamin D is a fat-soluble vitamin. This means it is soluble in fats and oils and can be stored for a long time in your body.
There are two dietary forms of vitamin D:
- Vitamin D3, also known as cholecalciferol. It is found in egg yolks, fatty fish, and other animal foods.
- Vitamin D2, also known as ergocalciferol. It is found in mushrooms, plants, and some yeasts.
Of these two, cholecalciferol (vitamin D3) is more effective at increasing vitamin D levels in the blood.
What does vitamin D do in your body?
For vitamin D to become active, it must undergo two conversion steps.
First, it is converted to calcidiol. This conversion takes place in your liver. Calcidiol is the storage form of the vitamin.
Then, calcidiol is converted to calcitriol in your kidneys. Calcitriol is the active form of the vitamin. It is the steroid form of vitamin D.
Calcitriol binds to the vitamin D receptor (VDR). VDR is found in almost every cell in your body.
When calcitriol binds to VDR, it either activates or deactivates the genes in your body, leading to changes in your cells. Other steroid hormones in your bodywork in the same way.
Vitamin D affects most body cells that are linked to bone health. For example, vitamin affects calcium and phosphorus absorption from your gastrointestinal tract.
However, medical researchers have discovered that this vitamin also contributes to other areas of health, such as anticancer effects and immune function.
Exposure to sunshine helps you to get vitamin D
Your skin has cholesterol in it. Exposing your skin to the ultraviolet B rays of the sun stimulates the production of vitamin D from this cholesterol.
If you live in a region with a lot of sunshine, you can get adequate sunlight. All you need do is sunbathe a few times per week.
It is important to note that you must expose a large part of your body to the sun. For example, your body won’t produce much of the vitamins if you reveal only your hands and feet.
Using sunscreen or staying behind glass will also reduce the number of vitamins your body can produce.
Ensure that you use sunscreen when staying for a long time in the sun. Sunshine isn’t bad – in fact, it is healthy, but sunburn can cause the skin to age prematurely and increase your risk of skin cancer.
If you intend to stay in the sun for a long time, go without sunscreen for at least 10 minutes, but not more than 30 minutes. After that, you can apply sunscreen before your skin starts to burn.
The human body can store the vitamin for weeks or even months. As such, you do not need to sunbathe every day, only occasionally.
On the other hand, if you live in an area with little sunlight, you’ll have to supplement your vitamin from foods. This is very important during the winter.
Best dietary sources of vitamin D
|Cod liver oil, 1 tablespoon (15 ml)
|1,360 IU / 34 mcg
|Salmon, cooked, 3 ounces (85 grams)
|447 IU / 11 mcg
|Tuna, canned in water, 3 ounces (85 grams)
|154 IU / 4 mcg
|Beef liver, cooked, 3 ounces (85 grams)
|42 IU / 1 mcg
|One large whole egg (D is found in yolk)
|41 IU / 1 mcg
|One sardine, canned in oil, drained
|23 IU / 0.6 mcg
Fatty fishes are excellent sources. However, you’ll have to eat them daily to get enough.
The best dietary source of vitamin D is fish liver oil. Cod liver oil is an excellent example. A single tablespoon of cod liver oil contains at least two times the RDI (reference daily intake) of this vitamin.
Some cereals and dairy products are fortified with vitamin D.
This vitamin is also present in egg yolks and some rare mushrooms.
Your healthcare provider may also recommend vitamin D injections.
Symptoms of vitamin D deficiency
Symptoms based on vitamin d deficiency icd 10 include:
- Frequent infections or illness
- Tiredness and fatigue
- Pains in the bone and the back
- Impaired wound healing
- Hair loss
- Bone loss
- Muscle pain
- Weight gain
Potential health benefits
- Reduced risk of fractures, falls, and osteoporosis.
- Improved strength
- Prevention of cancer
- It eases symptoms of clinical depression.
- Reduces the risk of type 1 diabetes mellitus
Don’t forget to optimize other nutrients
We hope you found the information shared in this vitamin D 101 article beneficial.
Before concluding the blog, we want to remind you that nutrients cannot work in isolation. Therefore, you must balance your nutrient intake.
According to several studies, fat-soluble vitamins work together, so it is essential to balance your vitamin A and K intake while supplementing with vitamin D3.
Tonika Bruce, MSN, RN, MBA. is an accomplished nurse leader, published author, and personal development expert passionate about advancing healthcare management and quality patient outcomes.
She taps into the years of experience in healthcare management to produce credible and easy-to-understand health and leadership content. Her exceptional work has been featured in reputable publications, including Forbes, Recruiter, Inc, and the Color of Wellness magazine.