Vitamin D, also known as “the sunshine vitamin”, stands out compared to other vitamins. This steroid hormone is synthesized from cholesterol after your skin is exposed to the Ultraviolet rays of the sun. Even though a healthy dose of sunshine can provide you with vitamin D, it is rarely enough. Supplements in this case are necessary to contribute the adequate amount. This vitamin is highly crucial yet around 41.6% of U.S. population are deficient.

Types of Vitamin D

Vitamin D is fat-soluble which means it dissolves in oil or fat causing it to be stores in the body for a long period of time. There are two types of Vitamin D: Vitamin D3 also known as cholecalciferol (found in fatty seafood and egg yolk, and Vitamin D2 also known as ergocalciferol (found in yeast and mushrooms).

The function of Vitamin D

Vitamin D goes through 2 forms to become activated.

Firstly, the liver converts the vitamin D Calcidiol 25(OH)D through the use of the enzyme vitamin D 25-hydroxylase. Then it is converted into its active steroid-hormone form that is known as calcitriol 1,25(OH)2D. The receptors of the vitamin D then interact with Calcitriol.

When vitamin D's active form interacts to this receptor, it activates or deactivates genes, causing changes in your cells. This mechanism of action is comparable to that of the majority of other steroid hormones. Vitamin D has an effect on a variety of cells involved in bone health. For instance, it facilitates calcium and phosphorus absorption from the intestines. Recently there have been studies on its impact on immune function and cancer protection.

Sunscreen is crucial if you go sunbathing or spend long periods of time in the sun. Sunshine is mostly healthy; however sunburns can result in wrinkles and even skin cancer. Applying a decent amount of sunscreen and checking for ones with at least SPF 30 is recommended by dermatologists.

Since vitamin D can be stored in your body for long period of times, a dose of vitamin D is required occasionally, however if you live in an area without plenty of sunlight, it Is highly recommended to find the adequate amount required through foods and supplements.



  • Decreased risk of osteoporosis, fractures, and falls. This can be very important for elderly.
  • Increased strength. Vitamin D can help strengthen the muscles throughout the body.
  • Preventing cancer. Vitamin D may aid in the prevention of cancer. According to one study, 1,100 IU per day when combined with calcium lowered cancer risk by 60%.
  • decreases depression. Vitamin D has been shown in studies to reduce patients symptoms
  • Decreased risk of developing type 1 diabetes.

Disclaimer that many of the results are not fully studied, more evidence is required to confirm this.

Amount of Vitamin D to Take

Your healthcare professional will determine the vitamin D storage form, calcifediol. Any value less than 12 ng/ml is deemed insufficient, whereas any value greater than 20 ng/ml is regarded acceptable. Many health care professionals recommend 40 ng/ml for optimal results.

Here is the RDI for Vitamin D

  • 400 IU (10 mcg): infants, 0–12 months
  • 600 IU (15 mcg): children and adults, 1–70 years old
  • 800 IU (20 mcg): older adults and pregnant or breastfeeding women

The National Academy of Medicine of the United States of America recommends a safe upper limit of 4,000 IU (100 mcg) per day.

Vitamin D3 pills tend to be more effective than vitamin D2 supplements at increasing vitamin D levels. D3 capsules can be found in the majority of supermarkets and health food stores, as well as online.


What will happen if you take too much

Vitamin D toxicity is extremely uncommon and occurs only when extremely high dosages of vitamin D are taken over a lengthy period of time.

Confusion, inability to concentrate, tiredness, sadness, vomiting, stomach discomfort, constipation, and elevated blood pressure are the primary signs of poisoning.


Nutrients work together

It's critical to remember that nutrients rarely function in isolation. Several nutrients are interdependent, and increasing your consumption of one nutrient may result in an increased requirement for another.

According to some experts, fat-soluble vitamins function synergistically and it is critical to maximize vitamin A and K intake while supplementing with vitamin D3.

This is especially true for vitamin K2, another fat-soluble vitamin that the majority of people are deficient in.

Magnesium, another critical mineral that is frequently deficient in the modern diet, may also be necessary for vitamin D function.


How To Know If You Are Deficient

Vitamin D deficiency is one of the most common. Certain individuals are at a greater danger than others. 41.6 percent of the overall population in the United States is vitamin D deficient. Elderly people are significantly more likely to be inadequate. Immunocompromised individualizes are also at a higher probability of being deficient. According to a study, 96% of those who had heart attacks were vitamin D deficient. Symptoms of deficiency are usually subtle and can take years to acknowledge

Rickets, a bone condition common in children in underdeveloped nations, is the most well-known indication of vitamin D insufficiency. Rickets has been mostly eradicated among Western countries as a result of vitamin D fortification of certain foods. In older persons, deficiency is also associated with osteoporosis, decreased bone density, and an increased risk of falls and fractures.

Studies show that Vitamin D deficiency significantly increases the risk of heart disease, type 1 and type 2 diabetes, cancer, dementia, and autoimmune illnesses such as multiple sclerosis. Vitamin D deficiency is associated with a decreased lifespan. Nonetheless, it is unknown whether insufficiency causes these disorders or whether those with low levels are just more susceptible to develop them.



Vitamin D is a fat-soluble vitamin that plays a critical role in bone health. Increased consumption may also help alleviate depression and enhance strength in persons who are deficient. When exposed to sunshine, your skin creates vitamin D. Vitamin D is also found in foods such as fatty fish, fish oil, and liver, as well as some fortified foods and supplements. Deficiency is quite prevalent due to restricted exposure to sunshine and a limited range of nutrient-dense foods. Consider supplementing if you spend little time in the sun and consume little fatty seafood. Getting enough vitamin D can significantly improve your health.



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