Why is it not advisable to take megadoses of vitamin D at once?
Taking 50,000 IU of vitamin D or more at once is dangerous for the body, as there is no such reserve of magnesium and calcium in the body to absorb it. Therefore, the body will leach calcium from the bones, leading to osteoporosis. The maximum recommended daily dose of vitamin D is 10,000 IU.
The absorption of vitamin D requires activation and the involvement of other substances — primarily magnesium (to convert it to its active form) and calcium (to perform its main function — regulating the levels of calcium in the blood and tissues).
When a person takes a megadose of vitamin D all at once — for example, 50,000 or 100,000 IU at a time — they sharply increase the body's demand for magnesium and calcium. However, the body does not have such reserves of these minerals to immediately support such a large dose of vitamin.
Magnesium begins to deplete quickly, which can lead to cramps, fatigue, arrhythmias, and other symptoms of deficiency.
There will not be enough calcium for such doses, and the body will extract it from the bones — which weakens bone tissue and can lead to osteoporosis over time.
Thus, the intake of vitamin D should be gradual and balanced, especially at high dosages. Without support from magnesium and calcium, megadoses do not provide benefits and can cause direct harm.
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