Vitamin D is not only a vitamin, but also acts as a hormone in the body. When a substance similar to cholesterol in skin cells is exposed to ultraviolet B rays from sunlight, it turns into prohormone vitamin D and plays a very important role in our health, especially in our immune system. As is the case with the covid-19 disease, which is currently on our agenda quite a lot. Studies have shown that the level of vitamin D in the blood determines the course of covid19 disease. Those with vitamin D deficiency may have covid-19 more severely (1,2,3).
Sunbathing the face, arms and legs for 20 minutes without using sunscreen at least 3 times a week between 10:00 and 15:00 is sufficient for vitamin D synthesis. It meets our vitamin D need 80-100%.
GOOD SOURCES OF VITAMIN D
There are two types of vitamin D: D2 and D3. It can be taken with the sun as well as through food. Plant-based vitamin D2 is found in algae and cultivated mushrooms. Vitamin D3 is found in fatty fish, milk, egg yolk, and liver, especially (4).
- 85g cooked salmon: 238 IU
- 85 grams of sardine: 408 IU
- 85g canned tuna: 136 IU
- 85 g liver: 42 IU
- 1 egg yolk: 25 IU
- 1 glass of milk: 98 IU
- 30 g cheese: 12 IU
- 1 teaspoon of butter: 60 IU
WHO ARE AT RISK OF VITAMIN D DEFICIENCY?
- Living in a place without sun
- Over the age of 50
- Those who use epilepsy, cortisone, cholesterol, chemotherapy drugs
- Patients with kidney failure
- Women in hijab
- Dark skinned
- Obese individuals (In obese individuals, vitamin D accumulates in fat cells in the body and cannot be used by the body.)
WHAT IS THE IDEAL LEVEL OF VITAMIN D IN THE BLOOD?
If the level of vitamin D in the blood is less than 10 ng / ml, there is severe vitamin D deficiency. In individuals with vitamin D deficiency, calcium intake cannot be absorbed either. If vitamin D deficiency persists, pain begins in bones and muscles, and then osteoporosis. In addition, mental illnesses such as depression may occur (5).
If the vitamin D level is higher than 30 ng / ml, it is sufficient. The most ideal level is 40-60 ng / ml.
It is more appropriate to be between 75-100 ng / ml in patients with autoimmune disease (hashimoto, type-1 diabetes, multiple sclerosis, etc.). It should be between 60-100 ng / ml in osteoporosis and cancer patients.
HOW TO DETERMINE VITAMIN D DEFICIENCY?
In order to determine the vitamin D level, 25 (OH) D3 level should be measured in the blood. If there is a deficiency, VITAMINI D3 supplement should be used. Within 5-10 days of taking the supplement, vitamin D in the blood rises. It decreases a little after 20 days and this situation continues to increase in the next 10-15 days. This situation can vary from person to person, so after 20 days of taking vitamin D, vitamin D in the blood should be checked again.
When vitamin D supplements are overdosed and the blood level is above 150 ng / ml, toxic effects (heart rhythm disorder, kidney stone formation, vomiting, etc.) are seen. Therefore, it should be used under doctor / dietician control.
HOW SHOULD VITAMIN D SUPPLEMENTS BE USED?
The need for vitamin D; It may vary depending on factors such as age, country of residence, hijab status. Dietary Reference Intake is as follows below(4)
- 0-12 months baby: 400 IU
- 1-13 years old: 600 IU
- 14-18 years old: 600 IU
- 19-50 years old: 600 IU
- 51-70 years old: 600 IU
- > 70 years old: 800 IU
Adult individuals who say they cannot have the blood test and cannot sunbathe can use a maximum of 4000 IU supplements according to EFSA (European Food Safety Authority). However, if your blood vitamin D levels are low and you don't know, this supplement won't change much. Likewise, if your blood level is high, toxic effects may occur. Therefore, your priority should always be to use the recommended dosage of supplements after the test.
Vitamin D is a fat-soluble vitamin, so it is beneficial to consume supplements with oil sources such as olive oil for better absorption.
NOTE: Vitamin D level is evaluated differently in patients with kidney failure, you should consult your doctor.
- Nutrients. 2020 Apr 2;12(4):988. doi: 10.3390/nu12040988.
- Glob Antimicrob Resist. 2020 Sep;22:133-134. doi: 10.1016/j.jgar.2020.05.006.Epub 2020 May 29.
- J Infect Public Health. 2020 Oct;13(10):1373-1380. Doi: 10.1016/j.jiph.2020.06.021.Epub 2020 Jun 20.
- NIH, Vitamin D Fact Sheet for Health Professionals: https://ods.od.nih.gov/factsheets/VitaminD-HealthProfessional/
- Özata M. Yaşamı destekleme sanatı. Hayykitap:İstanbul.
- Smith M. Contemporary Nutrition 8th Edition. Mc Graw Hill: NewYork