When taking vitamin D3 in the form of food supplements, one should always adhere to the recommended daily dose. An excess of vitamin D3 is not bad, it is excreted through the urinary tract in the human organism.
The vitamin D level can be determined by a blood test at a doctor's office. This is often determined if a vitamin D deficiency is suspected. Insufficient vitamin D formation is caused by a reduction in sunlight, especially in the winter months.