Why is Vitamin D Important to Our Health?
Ria Mittal
why is vitamin d important for health

What is Vitamin D? 

Vitamin D is a fat-soluble solid that helps the body absorb and retain calcium and phosphorus. These are nutrients that keep bones, teeth, and muscles healthy.  

There are different types of vitamin D, D2 and D3. Both are produced due to the sun’s ultraviolet rays. However, D3 is naturally produced by animals, including humans, while D2 is produced in plants. D2 and D3 correct vitamin D deficiency, but most doctors recommend D3 because it is slightly more active and therefore slightly more effective. 

Why is vitamin D Important to our health? 

Vitamin D Benefits 

May Protect Against Respiratory Infections

A study of 25 randomized controlled trials with 11,300 people indicates that individuals with insufficient levels of vitamin D experienced a 12% decrease in the likelihood of respiratory infections upon taking a vitamin D supplement. 

Having a healthy amount of vitamin D can boost the immune system and potentially prevent illnesses such as the flu or common cold. 

Helps with Bone Health and Muscle Strength

Especially when older, bone health and muscle strength can be of concern. As aforementioned, vitamin D helps with absorption of calcium and phosphorus, which can be stored in the bone. If there is not enough vitamin D, there will not be enough of calcium’s active form, the hormone calcitriol. A deficiency of vitamin D may lead to Osteoporosis. 

In fact, an analysis of 12 randomized, controlled studies found that higher daily intakes of vitamin D supplements (500 to 800 IU) reduced certain fractures by around 20%, while lower intakes (400 IU or less) did not offer any benefit of fracture prevention. 

May Reduce Risk of Heart Disease, Type 2 Diabetes, and Autoimmune Diseases 

Vitamin D receptors are present in the heart, and it also regulates regulatory effects on specific immune and inflammatory cells involved in cardiovascular disease. Additionally, adequate levels of vitamin D promote arterial flexibility and relaxation, contributing to the management of high blood pressure.

Vitamin D, according to certain observational cell model studies, may assist in the increase of insulin sensitivity, boost beta cell function, and lessen inflammation. These all potentially reduce the risk and help manage type 2 diabetes.  

As for other autoimmune diseases, a study published in the BMJ, found that of 26,000 participants, those who took vitamin D had a significantly lower risk of autoimmune disease. 

May Help with Mood Regulation and Mental Health 

Vitamin D’s role in helping with clinical depression is still unclear due to limited research. However, certain studies have found that vitamin D has a role in mood regulation and decreasing negative emotions. Additionally, a deficiency of vitamin D is seen to exacerbate mental illnesses such as seasonal affective disorder (SAD), according to the NIMH. Vitamin D can be produced from sunlight exposure, and the wintertime often has less sunlight, inhibiting serotonin levels for those with SAD. 

May Help Reduce Cancer Death

While there have not been enough studies with consistent associations between vitamin D and reducing cancer, researchers believe that there may be a correlation between the two. 

Lab studies have found that vitamin D can hinder tumor development and of existing ones in the breast, ovary, colon, prostate, and brain. And in humans, epidemiological studies have shown that higher levels of vitamin D are associated with lower rates of colon, pancreatic, prostate, and other cancers. 

Animal and laboratory studies have found that vitamin D can inhibit the development of tumors and slow the growth of existing tumors including those from the breast, ovary, colon, prostate, and brain. In humans, epidemiological studies show that higher serum levels of vitamin D are associated with substantially lower rates of colon, pancreatic, prostate, and other cancers, with the evidence strongest for colorectal cancer

May Help Prevent Cognitive Decline and Dementia

There are vitamin D receptors in brain tissue, suggesting it impacts cognitive function and perhaps dementia. Additionally, studies have shown that deficiency of vitamin D is potentially linked to higher risks of dementia.

Since we have answered the question: why is vitamin D important to our health, let’s discuss how we can achieve a healthy amount. 

How Much Vitamin D is Healthy?

According to an article from Healthline, here is the recommended amount of vitamin D for various demographics: 

  • Infants (0–12 months): 10 mcg (400 IU)
  • Children and teens: 15 mcg (600 IU)
  • Adults ages 18–70: 15 mcg (600 IU)
  • Adults over age 70: 20 mcg (800 IU)
  • Pregnant or breastfeeding women: 15 mcg (600 IU)

Obtaining the recommended amount of vitamin D will help maintain healthy bones and calcium levels. 

However, there are certain demographics that can be susceptible to vitamin D deficiency due to various factors. These can include:

  • Living in an area with high pollution levels
  • Spending most of your time indoors
  • Living in a big city (the buildings block sunlight)
  • Having darker skin (with higher levels of melanin, your skin absorbs less vitamin D). 
  • Having skin tags.

People who face these conditions may need additional vitamin D; however, it is important to consult with a doctor. 

How to get Sufficient Vitamin D? 

The Sun 

The sun is a natural source of vitamin D. When skin is exposed to sunlight, the UV radiation converts certain molecules into vitamin D. Getting 10 to 30 minutes of sunlight multiple times during the week allows the body to produce enough of the vitamin for some people. However, some people may require additional supplements to produce a healthy amount of vitamin D.


There are many foods that provide vitamin D: 

  • salmon
  • sardines
  • herring
  • canned tuna
  • cod liver oil
  • beef liver
  • egg yolk
  • shrimp
  • regular mushrooms
  • Milk (fortified with vitamin D) 
  • Yogurt (fortified)
  • Orange juice (fortified)

Fortified means additional nutrients were added. 


One can buy vitamin D supplements from pharmacies, however it is important to check with a doctor beforehand to ensure you obtain the correct dosage. Getting too much vitamin D can be unhealthy as well. 


Vitamin D is extremely important for the body. For this reason it is important to get outside and get sunlight along with eating foods that contain vitamin D. This will benefit the body with many health advantages.

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