Vitamin D or calciferol is a fat-soluble vitamin commonly called the “sunshine vitamin.” That’s because it’s not only a nutrient found in food, but we produce it when ultraviolet (UV) light from the sun strikes our skin and triggers its creation.
All vitamin D — whether obtained from food, sun exposure, or supplementation, is biologically inactive. It has to undergo two processes in the body to become active. These conversion processes take place in the liver and kidneys.
Scientists now realize that there are vitamin D receptors in almost every single cell in the body. So this vitamin has many benefits that make it critical for almost all aspects of health. Some research has found it even supports the health of DNA and chromosomes.
Vitamin D’s Many Roles in the Body
Vitamin D promotes your body’s ability to absorb calcium, a primary building block of bone. Without enough vitamin D, bones can become brittle, thin, or misshapen. In concert with calcium, vitamin D supports normal bone density.
Vitamin D is required for normal brain development and supports brain health throughout old age. Research has found that vitamin supports cognitive health.
This vitamin is crucial to nervous system and muscle health — and can also help regulate the production of certain inflammatory chemicals, called cytokines.
Vitamin D also affects both arms of the immune system by stimulating specific immune responses. Because of its role in immune health. Vitamin D supports the health of the respiratory tract.
Vitamin D also supports blood pressure and cardiovascular health.
Unfortunately, the 2015-2016 government NHANES study found that 92% of men and 97% of women consumed less than the recommended amounts of vitamin D.
How Do People Become Deficient in Vitamin D?
There are a number of ways people may fail to get enough vitamin D:
Age. Older individuals aren’t able to synthesize vitamin D as well as younger people. Plus, they tend to spend more time indoors and may have lower dietary intake of the vitamin. And sadly, our bodies produce less vitamin D with age, even though our need for it increases.
Weight Issues. Body fat can bind with vitamin D, which stops it from getting into the bloodstream.
Diet. Some people fail to get sufficient vitamin D in their diets.
Health Concerns. Certain health problems cause problems with 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 impact exposure include smog and the use of sunscreen.
Medications. Certain drugs can interfere with the ability of the body to convert or absorb vitamin D.
Race. People with darker skin have a reduced ability to synthesize vitamin D from sunlight.
Smoking. This habit interferes with vitamin D metabolism, among its other hazards.
Excess Vitamin A. In the body, vitamin A functionally competes with vitamin D. Consumption of excess vitamin A, as found in some multivitamin formulas and cod liver oil, can neutralize the positive effects of vitamin D.
3 Ways to Gain Vitamin D’s Health Benefits
There are three separate ways to get the vitamin D health benefits you need:
Skin. Vitamin D researchers suggest that from 5 to 30 minutes of sun exposure between 10 in the morning and 4 in the afternoon most days will provide sufficient vitamin D synthesis. Of course, moderation is necessary.
Diet. Few foods contain vitamin D naturally. Fatty fish and fish oils are some of the best sources. Animal-based foods provide some vitamin D, although a small amount is found in mushrooms. And some foods have been fortified with added vitamin D.
Supplementation. Since too much sunlight exposure can cause skin aging, some people take vitamin D supplements. According to the National Institutes of Health, vitamin D3 increases blood levels of the vitamin to a greater extent and maintains levels longer than the D2 form of the vitamin.
If you wonder whether you have enough vitamin D, you may want to ask your physician to run a simple lab test to measure your levels when you go for your next physical exam.
Please note, however, that excess levels of vitamin D can also be toxic. Vitamin D supplements can also interact with some medications, including steroids and statins. Therefore, it is best to work with your doctor and have your levels checked regularly.