This vitamin is classified as a hormone, but it is actually a prohormone – a substance converted to a hormone within the body. Chemical alterations to vitamin D take place within the kidneys and secrete it as a hormone.
It is essential in numerous processes in the body, as it controls blood calcium levels, helps its absorption and utilization, inhibits the release of the parathyroid hormone, which is critical to bone health, fortifies the immune system, and much more.
BBC News says that vitamin D is important because:
“Its main function is to regulate the amount of calcium and phosphate in the body, which are vital for the growth and maintenance of healthy bones, teeth, and muscles. In extreme cases, low levels can lead to rickets in children — where the bones become soft and weak and misshapen as they continue to grow.
In adults, vitamin D deficiency can lead to osteomalacia — causing severe bone pain and muscle aches. But there is a balance — too much vitamin D can lead to high levels of calcium in the blood which can cause heart and kidney problems.”
Namely, it also prevents infections and illnesses, prevents diabetes, heart disease, multiple sclerosis, and hypertension, reduces the risk of breast, colon, and prostate cancer, and neurodegenerative diseases.
Dr. Mercola explains:
“A growing body of evidence shows that vitamin D plays a crucial role in disease prevention and maintaining optimal health. There are about 30,000 genes in your body, and vitamin D affects nearly 3,000 of them, as well as vitamin D receptors located throughout your body.
According to one large-scale study, optimal Vitamin D levels can slash your risk of cancer by as much as 60 percent. Keeping your levels optimized can help prevent at least 16 different types of cancer, including pancreatic, lung, ovarian, prostate and skin cancers.”
The primary source of this vitamin for our body is sunlight, as even the shortest exposure to sun triggers its production.
You can also get it from food and supplements, which is absorbed by the intestines and transferred to the liver, which turns it into a form that can be freely circulated throughout the body. The kidneys turn the vitamin D into calcitriol – a biologically-active form of “D.” The adequate synthesis of this vitamin is vital for the calcium absorption and reabsorption in the small intestine and kidneys.
These are the most common modifiable risk factors that contribute to vitamin D deficiency:
- Sedentary lifestyle
- Calcium intake
- Body weight and composition
- Improper sunscreen use
Non-modifiable risk factors include:
- Female sex
- Older age
- Non-white ethnicity (blacks and Latinos are at a much higher risk, as mentioned)
- Diagnosis of inflammatory bowel disease or cystic fibrosis (possibly chronic kidney disease)
Despite these, this issue can be a result of various other factors, and these are some of the hidden causes:
1. Lack Of Sunlight
Getting enough sunlight is the main cause of vitamin D deficiency. Note that proper application of sunscreen does not impair the ability of the skin to produce vitamin D.
2. Age
As a result of aging, our body loses its ability to synthesize vitamin D, so the elderly need to take vitamin D supplements.
3. Crohn’s Disease
Crohn’s, an inflammatory bowel disease (IBD), interferes with the function of vitamin D. Intestinal inflammation inhibits its absorption. Also, this deficiency might also be caused by ulcerative colitis.
4. Darker Skin
Latinos and African-Americans are disproportionately affected by this issue, due to their darker complexion, and melanin, concentrated in the upper skin layers, if in high amounts, interferes with vitamin D synthesis.
5. Kidney Disorder
Disorders of the kidney, including kidney disease, can lead to numerous health issues, including a lack of this vitamin in the body. As the disease progresses, the liver produces proteins called fibroblast growth factor, which block the metabolism of vitamin D in the body.
6. Obesity
Excess fat in cells “sucks up” too much vitamin D, and thus lowers its levels in the body.
7. Cystic Fibrosis
Cystic fibrosis, a progressive genetic disease, leads to lung infections and difficulty breathing. Besides damaging the lungs, cystic fibrosis may also cause gut problems. Whenever the gut is affected, complications may arise in the proper absorption of fat. This, in turn, disrupts absorption of fat-soluble nutrients such as vitamin D.
8. Gastric-Bypass Surgery
This popular treatment for obesity can complicate the function of vitamin D, as it removes a large part of the intestine, which affects the amount of vitamin D absorbed by the body.
9. Whipple’s Disease
This is a rare intestinal infection caused by bacteria called Tropheryma whipplei. It negatively affects the ability of the body to break down food components, like fats, carbohydrates, and proteins, and blocks the intestinal openings, inhibiting the proper absorption of vitamin D.
10. Celiac Disease
Celiac disease is an immune reaction to gluten, a type of
protein in wheat, barley, and rye. It causes numerous digestive issues,
including the difficulty for the body to absorb certain nutrients, such
as D vitamin.
The most common way to diagnose this issue is a blood test, and anything less than 20 ng/mL is diagnosed as a deficiency.
To correct vitamin D deficiency, you should increase the exposure to sunlight for between 10 to 30 minutes daily, several times per week. Moreover, you should consume foods like fresh fish, egg yolks, fortified dairy products, fortified grains, and fish liver oils.
According to the George Mateljan Foundation, which a not-for-profit food and nutrition science organization:
- Four ounces of wild-caught Alaskan sockeye salmon satisfies 128 percent of the RDA
- 3.2 ounces of sardines — 44 percent of the RDA
- One egg — 11 percent of the RDA
- Shiitake mushrooms — 5 percent of the RDA
According to the Institute of Medicine, the recommended dietary allowance (RDA) of vitamin D is 600 international units (IU) for people aged 1 to 70, and 800 IU for people older than 70. The safe amount of this vitamin that can be consumed for most people is 4,000 IU daily.
However, note that the insufficient magnesium levels in the body can also inhibit the activation of vitamin D in the body. Therefore, Mohammed Razzaque, professor of pathology at Lake Erie College of Osteopathic Medicine in Pennsylvania says:
“People are taking vitamin D supplements but don’t realize how it gets metabolized. Without magnesium, vitamin D is not really useful. By consuming an optimal amount of magnesium, one may be able to lower the risks of vitamin D deficiency, and reduce the dependency on vitamin D supplements.”
