Why such a high dose — 4000 IU per capsule? — Vitamin D3 Food Supplement, N90- VitalHarmony

The figure of 40,000 IU in the product name is neither a single dose nor the total per pack: according to the label, the 90 capsules contain a total of 360,000 IU. Each capsule contains 4000 IU (100 µg) of cholecalciferol — a high but common dose for adults who are deliberately making up for a deficiency or maintaining their vitamin D levels in autumn and winter.

This format is chosen when the standard 400–1000 IU from multivitamins is not enough: for example, with an office lifestyle, infrequent walks outdoors or living in regions with short daylight hours. Vitamin D3 in the form of cholecalciferol is the same form the body synthesises under the influence of ultraviolet light, so it is well studied and widely used in supplements.

Because the dose is high, during a long course it makes sense to check your blood 25(OH)D level periodically and follow your doctor's recommendations. The capsules are intended for adults — 1 a day, and the recommended dose must not be exceeded. The supplement is not recommended during pregnancy and breastfeeding and should not be taken if you have an individual intolerance to any of the ingredients; the label advises consulting a doctor before use, especially if you are taking several supplements at once. The capsules may contain traces of milk (including lactose), soy, peanuts, other nuts, sesame, cereals containing gluten, eggs and crustaceans — take this into account if you have any of these allergies.