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Stating that vitamin D deficiency is common in our country, iHealth member JCI Antalya hospital clinic Endocrine Surgery Specialist Prof. Doctor, “Because it is not known exactly how to store it. For example, people think that they get plenty of vitamin D when they sunbathe for hours. However, on the contrary, as you tan, the synthesis of this vitamin in the skin decreases, while the risk of cancer increases,” she said.

Especially during the pandemic period, the richest source of vitamin D, the importance of which is better understood by its effect that strengthens immunity, is the sun. ‘However, it is also necessary to use the sun correctly,’ said Endocrine Surgery Specialist Professor Doctor explained the ways of storing this vitamin, which allows us to protect ourselves from many diseases, from bone resorption to cancer, as follows.

What foods does it contain?

Vitamin D is an essential vitamin for our body and is considered a “hormone” today. One of the most important functions is to ensure the absorption of calcium taken with food from the intestines. Of the nutrients, 10-20 percent is synthesized in the skin, and the rest is synthesized by Ultraviolet B (UVB) radiation. Foods that are a source of vitamin D are fatty fish, especially salmon, tuna, mushroom species, milk and eggs. Solar energy converts the 7-dehydrocholesterol in the skin into vitamin D3. Vitamin D3 is transported to the liver and kidneys. The kidneys convert vitamin D3 into active vitamin D.

Is excess harmful?

Although there is no consensus about the “optimal” level of vitamin D, most researchers consider the level of this vitamin above 30 ng/ml to be sufficient, the level between 20 and 30 ng/ml to be insufficient, and the level below 20 ng/ml to be deficient. There are many studies showing that vitamin D levels below 20 ng/ml negatively affect bone health, but there is no consensus on the optimal level of vitamin D for bone health. Therefore, some researchers argue that the level of vitamin D should be at the level of 70-80 ng/ml. In cases where the level of vitamin D is more than 150 ng/ml, vitamin D intoxication (poisoning) may be considered. Therefore, it is not recommended to keep it above 100 values in general.

What are the causes of vitamin D deficiency?

The most important reasons of vitamin D deficiency in old age, color dark skin, obesity, the use of drugs that accelerate the metabolism of vitamin D, inadequate or too much sun exposure, osteoporosis (bone loss), nontravmatik (spontaneously) broken formation, osteomalacia, absorption disorders, chronic renal failure, chronic liver disease and mean parathyroid hormone is the height of magnesium ammonium phosphate. This vitamin is very important for the immune system (immunity), and there are vitamin D receptors in the cells of the immune system. With an increase in antibodies in autoimmune diseases, vitamin D cannot bind to these receptors. The level of vitamin D in Hashimoto’s thyroid disease is usually low. In addition, a low level of vitamin D also sets the stage for the development of autoimmune diseases.

How to store it naturally?

Unlike UVB, the sun’s UVA rays stimulate the melanin cells in the skin to provide tanning, but do not contribute to the production of vitamin D. Even excessive tanning, which develops with UVA, prevents the contact of UVB rays that synthesize vitamin D with the deep layers of the skin, preventing the production of vitamin D. UVB rays, on the other hand, do not pass through glass and clothing. Therefore, when using preservatives above a protection factor of 20, vitamin D synthesis does not occur by sunbathing behind glass and tulle. For this, the sun’s rays must come into contact with the skin. Since the synthesis of vitamin D in the skin does not begin immediately, a shower should not be taken immediately after sunbathing.

If necessary, you should take a shower with warm water without using soap and shampoo. UVB rays reach the earth at the Zenith angle, and this angle is important for the synthesis of vitamin D. Therefore, the distance of countries to the equator is important. May – November are suitable months for vitamin D synthesis in our country. The Zenith angle, on the other hand, is suitable for the synthesis of vitamin D between 10.00 and 15.00. Therefore, in these months and hours it is enough to go out into the sun for 15-20 minutes. Vitamin D equivalent to 20 thousand IU is synthesized in the skin when the sun is out at this time in summer, when the skin is thick enough to form a slight pinkness. If only the hands, arms and legs are exposed to the sun, 3000 IU of vitamin D is synthesized.


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President of Organ Transplant Center at MedicalPark Hospital Antalya

Turkey's world-renowned organ transplant specialist. Dr. Demirbaş has 104 international publications and 102 national publications.

Physician's Resume:

Born on August 7, 1963 in Çorum, Prof. Dr. Alper Demirbaş has been continuing his work as the President of MedicalPark Antalya Hospital Organ Transplantation Center since 2008.

Prof. who performed the first tissue incompatible kidney transplant in Turkey, the first blood type incompatible kidney transplant, the first kidney-pancreas transplant program and the first cadaveric donor and live donor liver transplant in Antalya. Dr. As of August 2016, Alper Demirbaş has performed 4900 kidney transplants, 500 liver transplants and 95 pancreas transplants.

In addition to being the chairman of 6 national congresses, he has also been an invited speaker at 12 international and 65 national scientific congresses. Dr. Alper Demirbaş was married and the father of 1 girl and 1 boy.


Eczacibasi Medical Award of 2002, Akdeniz University Service Award of 2005, Izder Medical Man of the Year Award of 2006, BÖHAK Medical Man of the Year Award of 2007, Sabah Mediterranean Newspaper Scientist of the Year Award of 2007, ANTIKAD Scientist of the Year Award of 2009, Social Ethics Association Award of 2010, Işık University Medical Man of the Year Award of 2015, VTV Antalya's Brand Value Award of 2015.


Doctor of Medicine Degree Hacettepe University Faculty of Medicine Ankara, General Surgeon Ministry of Health Turkey EKFMG (0-477-343-8), University of Miami School of Medicine Member of Multiple Organ Transplant, ASTS Multiorgan Transplant Scholarship. Lecturer at Kyoto University. Lecturer at University of Essen, Research assistant at the University of Cambridge .

Professional Members:

American Society of Transplant Surgeons, American Transplantation Society Nominated, Middle East and Southern Africa Council Transplantation Society 2007, International Liver Transplantation Association, Turkish Transplantation Association, Turkish Society of Surgery, Turkish Hepatobiliary Surgery Association.


Our website contents consist of articles approved by our Web and Medical Editorial Board with the contributions of our physicians. Our contents are prepared only for informational purposes for public benefit. Be sure to consult your doctor for diagnosis and treatment.
Medically Reviewed by Professor Doctor Alper Demirbaş
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