Vitamin D3 deficiency is an important public health problem in Poland. It is commonly known that vitamin D3 has beneficial effects not only on regulating calcium and phosphorus metabolism, but also in the prophylaxis and treatment of many diseases.

WHERE DOES THE ORGANISM OBTAIN VITAMIN D3?

Three sources of obtaining vitamin D3 by human body are known. The first and most important source of this vitamin is skin synthesis, another source is diet, and then supplementation.

  • Skin synthesis of vitamin D3

This is the most important source of obtaining vitamin D3 by the human body. It is estimated that skin synthesis may cover around 80-90% of daily vitamin D3 requirement. We should add here that in Poland, skin synthesis is effective only in spring and summer (from May to September), between 10 a.m. and 3 p.m., with minimum 15-minute daily exposure to sunlight with uncovered arms and legs. In such conditions, the level of produced vitamin may reach approx. 2,000-4,000 IU. Unfortunately, between October and April, this method of obtaining vitamin D3 has low effectiveness.

  • Diet

Diet is an alternative form of obtaining vitamin D3 by humans. A well-balanced diet may cover approx. 20% of the daily requirement. The most important sources of this vitamin are primarily fish such as wild salmon, herring, and also egg yolk or whole milk. Unfortunately, when skin synthesis of vitamin D3 is insufficient, diet alone is not enough, and optimal supplementation proves to be of key importance.

  • Diet supplementation

For the majority of the population living in Poland, supplementation with vitamin D3 proves to be of key importance in terms of covering the full requirement. The optimum dose of vitamin D3 in the form of a supplement can be determined in two ways. The most important factor in the determination of an individual dose is the knowledge of such parameters as age, body weight, time of the year, sunlight exposure, lifestyle, dietary habits and health condition. Another good way to determine an individual dose is testing the level of 25-OH vitamin D in blood. It is a very good method, however, not always required to select supplementation.

RECOMMENDATIONS ON VITAMIN D3 SUPPLEMENTATION BASED ON AGE AND LIFESTYLE

In the majority of cases, where skin synthesis recommendations are met, additional diet supplementation is not necessary, but it is still safe and recommended.

For children between 1 and 10 years of age, the safe recommended dose is 600-1,000 IU/day.

For youth between 11 and 18 years of age, the safe recommended dose is 800-2,000 IU/day.

For adults between 19 and 65 years of age, the safe recommended dose is 800-2,000 IU/day.

For people between 65 and 75 years of age, the safe recommended dose is 800-2,000 IU/day. Such a dose should be taken throughout the year, regardless of skin synthesis.

For people above 75 years of age, the safe recommended dose is 2,000-4,000 IU/day. Such a dose should be taken throughout the year, regardless of skin synthesis.

For pregnant and breastfeeding women, it is recommended that the concentration of 25-OH vitamin D in blood should be on the level of 30-50 mg/ml.

Obese people with BMI above 30 should use double doses recommended for their age group.

Chronically ill people who permanently take medications, suffering from autoimmunological diseases, hormonal disorders, allergies, metabolic or other diseases should always try to adjust their daily dose of vitamin D3 on the basis of 25-OH vitamin D test.

RECOMMENDATIONS ON SUPPLEMENTATION AFTER TESTING THE LEVEL OF 25-OH VITAMIN D IN BLOOD

The optimum level of 25-OH vitamin D in blood is 30-50 ng/ml. Depending on the test results, an individual supplementation dose is recommended.

  • 0-10 ng/ml – for such a low level, one should verify whether general recommendations were followed at all. The following initial doses are recommended: for children between 1 and 10 years of age – 3,000-6,000 IU/d, while for people above 10 years of age – 6,000 IU/d. 25-OH vitamin D testing should be repeated after 1-3 months of such treatment, until the level of 30-50 ng/ml is reached.
  • 10-20 ng/ml – in the case of deficiencies, one should always verify whether general recommendations were followed. If not, supplementation should be started according to recommendations, and then the level of 25-OH vitamin D should be tested again after 3 months. If supplementation was correct, the dose should be increased by 100%, and the level of 25-OH vitamin D should be tested again after 3 months.
  • 20-30 ng/ml – in deficiencies, one should always verify whether general recommendations were followed. If not, supplementations should be started according to recommendations, and then the level of 25-OH vitamin D should be tested again after 6 months. If supplementation was correct, the dose should be increased by 50%, and the level of 25-OH vitamin D should be tested again after 6 months.
  • 30-50 ng/ml – the optimum level of vitamin D3 in blood. With this result, it is recommended that general recommendations for the age group should be continued.
  • 50-75 ng/ml – if general recommendations were followed, it is recommended that the dose should be reduced by 50%, and the level of 25-OH vitamin D should be tested again after 3 months. If higher doses were taken, it is recommended that supplementation should be discontinued for 1 month and after that time, general recommendations for the age group should be followed.
  • 75-100 ng/ml – for such a high level of vitamin D3, one should check whether vitamin D3 was supplemented and in what dose. It is recommended that supplementation should be discontinued for 1-2 months. After that time, supplementation of minimum doses according to general recommendations can be resumed, until the level of 30-50 ng/ml is reached.
  • >100 ng/ml – if supplementation was used, it should be discontinued immediately, and the level of 25-OH vitamin D should be monitored every month. If it was not used, you should contact your doctor in order to eliminate other causes of such a high level.