Vitamin D or calciferol is a fat-soluble vitamin commonly referred to as the “sunshine vitamin.” That's because not only is it a nutrient found in food, but we produce it when ultraviolet (UV) light from the sun hits our skin and triggers its formation.

All vitamin D - whether obtained from food, through sunlight or through dietary supplements - is biologically inactive. It has to go through two processes in the body to become active. These conversion processes take place in the liver and kidneys.

Scientists now know that there are vitamin D receptors in almost every single cell in the body. So, this vitamin has many benefits that make it important for almost all aspects of health. Some research has found that it even supports DNA and chromosome health.

The many roles of vitamin D in the body

Vitamin D promotes the body's ability to absorb calcium, a main building block of bones. Without enough vitamin D, bones can become brittle, thin or misshapen. In combination with calcium, the vital substance supports normal bone density.

Vitamin D is required for normal brain development and supports brain health well into old age. Research has found that the vital substance supports cognitive health.

This vitamin is crucial for nervous system and muscle health - and may also help regulate the production of certain inflammatory chemicals called cytokines.

Vitamin D also influences both parts of the immune system by stimulating specific immune responses and is involved in maintaining cardiovascular health.

Unfortunately, the 2015-2016 government NHANES study found that 92% of men and 97% of women consume less than recommended amounts of vitamin D.

How does a vitamin D deficiency occur?

There are a number of ways people may not get enough vitamin D:

• Age: Older people are no longer able to synthesize vitamin D as well as younger people. They also tend to spend more time indoors and may get fewer vitamins from their diet. And unfortunately, as we age, our bodies produce less vitamin D, even though our need for it increases.

• Weight problems : Vitamin D is fat-soluble and partially tightly bound in body fat tissue, which means it cannot enter the bloodstream.

• Diet : Some people don't get enough vitamin D from their diet.

• Health problems : Certain health problems reduce the absorption or conversion of vitamin D.

• Reduced exposure to UV light: Some people are at risk because they spend much of their time indoors or live in a geographic area where there is less sunlight. Other environmental factors that influence exposure include smog and sunscreen use.

• Medications: Certain medications can affect the body's ability to absorb or convert vitamin D.

• Race: People with darker skin have a lower ability to synthesize vitamin D from sunlight.

• Smoking: This habit also affects vitamin D metabolism, among other dangers.

• Excess Vitamin A: In the body, vitamin A functionally competes with vitamin D. Consuming excess vitamin A, as found in some multivitamins and cod liver oil, can neutralize the beneficial effects of vitamin D.

3 Ways to Reap the Health Benefits of Vitamin D

There are three different ways to get the health benefits of vitamin D you need:

• About the skin: Vitamin D researchers suggest that 5 to 30 minutes of sun exposure between 10 a.m. and 4 p.m. most days ensures adequate vitamin D synthesis. Of course, moderation is necessary to avoid increasing the risk of skin cancer.

• Diet : Few foods contain natural vitamin D. Fatty fish and fish oils are some of the best sources. Animal foods provide some vitamin D, although a small amount is also found in mushrooms. And some foods have been fortified with the vital substance.

• Dietary supplements : Because too much sunlight can cause skin aging and increase the risk of skin cancer, some people take vitamin D supplements. According to the National Institutes of Health, D3 increases blood levels of the vitamin to a greater extent and maintains levels longer than the D2 form of the vitamin. The intake of vitamin K2 is also important, as this prevents excessive storage of calcium in the blood vessels.

If you are wondering whether you have enough vitamin D, you can ask your doctor to do a simple laboratory test to measure your levels at your next checkup.

However, please note that excess vitamin D can also be toxic. Vitamin D supplements may also interact with some medications, including steroids and statins. Therefore, it is best to work with your doctor and have your levels checked regularly.

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