Vitamin D: How Crucial Is It for Health?

Oct 23, 2021


Vitamin D: How Crucial Is It for Health?

Most scientists and medical practitioners deem Vitamin D an essential nutrient for optimal health, but did you know it technically isn’t a vitamin?

Though it was researchers of the early 20th century who discovered, labeled and categorized the essential vitamins (including D), it was their successors who developed our modern definition: “organic (carbon-containing) chemicals that must be obtained from dietary sources because they are not produced by the body's tissues.”

Here’s the catch:

Despite being one of the most famous and important of its brethren, vitamin D brazenly breaks from this definition. Unlike its siblings, your body must produce it when absorbed from its more renowned source -- sunlight -- or other foods and supplements. Vitamin D is actually a prohormone - the inactive precursor molecule from which a hormone is derived.

Through a unique and fascinating process, your tissues take vitamin D, absorbed by your sun-exposed skin or through food/supplements, on a journey throughout your body.

Starting in your fat cells, unusable vitamin D makes its way to your liver, where it enriches itself in oxygen and hydrogen, then journeys to your kidneys, where it refuels itself to completion. Only then do you have access to vitamin D (aka calcitriol) that can benefit your body.

Pretty fascinating right?

Now that you understand your natural production of the “sunshine vitamin,” let’s analyze this nutrient’s many vital influences on your body in our Living Proof Guide to Vitamin D:

Part 1: Health Benefits of Getting Sufficient Amounts

If you’re looking for an ally in your pursuit of optimal wellness, there are few better options than vitamin D.

This essential nutrient can positively influence many aspects of your physical, mental and emotional wellbeing, contributing to a stronger and healthier you.

Here’s a brief introduction to the primary ways proper vitamin D consumption can help your body:

Bones & Teeth

Vitamin D fortifies your bones and teeth with calcium and phosphorus from your food, keeping them healthy, strong and sturdy.

The “sunshine vitamin” can also help strengthen your muscles, making bone and teeth-breaking far less likely.

Immune Support - colds & flu

Your immune system is your body’s natural line of defense against bacteria, viruses, fungi and toxins that can make you ill.

A healthy supply of vitamin D can boost your immune system by minimizing inflammation, producing microorganism-fighting proteins and more. 

There happen to be vitamin D receptors and activating enzymes on the surfaces of all white blood cells ( a major part of your immune system). The role that vitamin D plays in keeping the immune system healthy is very complex. Low levels of vitamin D have been linked to an array of autoimmune conditions and increased rates of infections. For example, In 2009, the National Institute of Health warned that low vitamin D levels are associated with frequent colds and influenza.

Diabetes & Blood Sugar

Healthy levels of vitamin D in your body can help keep your blood sugar levels within a healthy range and enhance your natural sensitivity to insulin, reducing your risk for type 2 diabetes.

Brain & Mood

According to research from the National Institute of Health, Vitamin D can boost certain aspects of brain function, help improve your mood and reduce your risk for some mental illnesses such as dementia and depression.

Cardiovascular Health & Hypertension

While there’s no consensus that vitamin D can directly improve one’s cardiovascular health, research reveals that avoiding vitamin D deficiency can reduce one’s risk of chronic cardiovascular issues -- such as hypertension -- that can become life-threatening.

Part 2: Health Risks of Insufficient Amounts

Just as sufficient vitamin D consumption can enhance your wellbeing, insufficient consumption can detract from it.

Let’s analyze the troubling risks of vitamin D deficiencies to help you better grasp the essential nature of this nutrient:


Osteoporosis is a serious health condition that leads to brittle bones that can break easily.

Those who suffer from this affliction are at a higher risk of fractures in the hips, ribs, spine and more, which can greatly lower their quality of life. 

A lack of vitamin D contributes to weaker bones and higher risks of osteoporosis, which is particularly troubling among the elderly. 

Cardiovascular Conditions

According to Johns Hopkins Medicine, insufficient levels of Vitamin D can raise your risks of heart attacks, congestive heart failure and other issues that worsen cardiovascular health, like  high blood pressure and diabetes.

Impaired Immune System

Low levels of vitamin D can reduce your immune system’s innate and adaptive abilities to fight off biological invaders that can harm your body.

Over time, this can weaken your natural defenses against pathogens that can lead to a range of serious illnesses and infections.

Autoimmune Issues

Fascinating research from the National Institute of Health suggests that inadequate vitamin D consumption due to genetic or lifestyle factors may increase one’s risk of diminished autoimmune function.

Though more research is needed, these early findings suggest a possible link between poor vitamin D levels and diseases like lupus and multiple sclerosis.


While scientists debate whether vitamin D deficiency is a consequence or cause of obesity, recent research from the National Institute of Health reveals it “cannot yet be excluded as a cause of obesity.”

Similarly, other findings from UC Health reveal vitamin D deficiencies in up to 90% of obese people, which scientists ascribe to the fat-soluble nutrient’s capacity to “sequester” in excess fat cells rather than circulating in the bloodstream.

Neurological Diseases

Mental health studies in the past decade reveal a potential link between a lack of vitamin D and the occurrence of “neurodegenerative diseases such as amyotrophic lateral sclerosis, Parkinson's disease and Alzheimer's disease.”


Multiple studies have shown that low levels of vitamin D, which is essential for cognitive function, can increase one’s predisposition for depression.

How to Supply Your Body with Enough

Now that we know the importance of proper vitamin D consumption, let’s finish by breaking down the healthiest ways to absorb this essential nutrient:

Ample Sun Exposure 

Vitamin D may be the “sunshine vitamin,” but that does not mean everyone absorbs sunlight in the same way.

Studies show that people with darker skin tones are more likely to suffer from a vitamin D deficiency, which researchers often ascribe to differences in mineral metabolism, lifestyle and, primarily, a reduction in vitamin D absorption due to pigmentation.

For people with lighter skin tones, a great way to increase absorption of the “sunshine vitamin” is to get 10-30 minutes of midday sun daily. 

For those with darker skin tones, some studies now recommend upping that time to 60-90 minutes daily to help account for their reduction in sun absorption due to added melanin in the skin.


To supplement the vitamin D you receive from sun exposure, you need to know the amount of vitamin D to take and some quality sources.

Many experts recommend adults up to 70 years old consume 600 IU (international units) of vitamin D per day, but for those deficient in this essential fat soluble prohormone, upper limits of 4,000-5,000 IU per day may be necessary. Vitamin D is fat soluble, so there is a level that can be toxic, but the National Institutes of Health (NIH) say that vitamin D toxicity is unlikely at intakes under 10,000 IU per day.

Besides the sun, ideal sources of vitamin D include reputable supplements and foods like oily fish (salmon, sardines, mackerel) and egg yolks.

For any questions about nutrition, self-care or other healthy living protocols, feel free to contact us at any time.