Vitamin D: An Introduction
Vitamin D plays a major role in maintaining bone health. It helps the body effectively utilize calcium from the diet.
Some food sources of vitamin D include egg yolk, dairy, fatty fish, and grains. Exposure to sunlight is a major source of vitamin D. The UV rays in sunlight induce vitamin D production in the skin. About 15 minutes of exposure to sunlight is recommended to maintain optimal vitamin D levels.
In today's world, people may not have enough exposure to sunlight.
Sunscreens are commonly used to prevent sunburns and tans, thereby blocking UV rays and the production of vitamin D. A sunscreen of SPF 30 can reduce the amount of vitamin D produced on sunlight exposure by more than 90%.
Vitamin D Deficiency
The worldwide prevalence of vitamin D deficiency is very high, as high as 50%. Vitamin D deficiency leads to bone loss, pain, risk of fractures, and several disease conditions, like rickets and lupus.
Certain groups of people are at an increased risk of vitamin D deficiency. These include:
- Breastfed infants
- Dark-skinned people who have lesser sunlight exposure
- Individuals suffering from obesity, cystic fibrosis, Crohn's disease, celiac disease, and certain other diseases
Vitamin D Supplements: Are They For You?
Very few foods have enough vitamin D to reach recommended daily intakes, and sunshine can be unreliable in certain climates.
In these cases, vitamin D supplements can be taken in addition to food sources.
Make sure to talk to your doctor before taking vitamin D supplements.
Overdose can lead to vitamin D toxicity, which is dangerous.
Melanin and Vitamin D
Vitamin D production depends on several factors, including the color of your skin, duration of exposure, amount of skin exposed, and genetics.
People with darker skin have more melanin, the pigment responsible for skin color. This protects skin cells from harmful radiation damage.
Melanin also blocks the amount of UVB radiation that enters the skin, thereby reducing the amount of vitamin D produced. So people with darker skin tones are at a higher risk for vitamin D deficiency.
Genetics of Vitamin D Deficiency
Studies have found some genetic changes associated with vitamin D deficiency.
Two such genes are GC and VDR.
Let's see how they regulate vitamin D levels.
- The GC gene contains instructions for producing vitamin D binding protein that binds to the active form of vitamin D.
- Active vitamin D is then transported to target cells by this protein.
- Active vitamin D is released at the target cell and can bind to the Vitamin D Receptor produced by the VDR gene.
- This complex then binds to several other proteins to influence gene expression and calcium homeostasis.
This is especially seen in organs like the kidneys, bones, intestines, parathyroid glands, and the cardiovascular system.
Mutations or changes in the VDR gene affect vitamin D levels and can increase or decrease the sensitivity of the body to the effects of vitamin D.
Vitamin D Genetic Test
You can easily find out if you have any genetic variations that affect your vitamin D levels through a genetic test.
Most genetic tests provide your DNA information in the form of a text file, called the raw DNA data.
This data may seem like Greek and Latin to you. Xcode Life, can help you interpret it.
All you have to do is upload your raw data and order a nutrition report. Xcode Life then analyzes your raw data in detail to provide you with comprehensive nutrition analysis, including information on your vitamin D levels.