Vitamin D is stored in fat cells in the body. What does this information tell us? If we forget to take our daily supplement, it's no problem. We can make up for it. This behavior is valid for both children and adults, all year round.

We obtain 90% of vitamin D through sun exposure and only 10% from animal-based foods that contain fat. Over 60% of children and adults are deficient in vitamin D. This means they need daily supplements, even during summer. This is called continuous administration.

Anca Hoisescu, primary care endocrinologist: "It's more effective to take vitamin D with a glass of milk than with a glass of water, and it can be stored in adipose tissue and the liver, which is a good thing. Vitamin D can be stored in adipose tissue and released from there. The requirement is between 400 and 800 units".

Dr. Antonela Burlacu, primary care endocrinologist: "We need a constant dosage, appropriate to each age and physiological status. It's very important to know how high this deficiency is. Depending on how severe the deficiency is, you can start with 5000 units for 2 months or 2000 units for 2 months. If you have normal vitamin D levels, you can take 1500-2000 units per day".

At normal vitamin D levels in the blood, you will absorb 30% of the calcium present in food. In case of deficiency, less than 10% of calcium is absorbed. To avoid running out of calcium in the blood, the body extracts it from the bones, which is a dramatic situation in childhood, adolescence and menopause.

All immune system cells have receptors for vitamin D. It plays an important role in the so-called innate defense of the body. It is the first line of defense when you encounter a virus or bacteria. In acute infections, the normal dose of vitamin D you take daily can be increased on the recommendation of a doctor.