A pharmacist warning about vitamin D usually refers to the fact that, while vitamin D is important for bone health, immunity, and muscle function, taking too much can be harmful.
Important things to know about vitamin D:
- Too much vitamin D can cause high calcium levels
- Excessive supplementation may lead to hypercalcemia (too much calcium in the blood), which can cause nausea, constipation, weakness, confusion, or excessive thirst.
- Very high doses can affect the kidneys
- Long-term overuse may increase the risk of kidney stones or kidney problems in some people.
- More is not always better
- Taking large “megadoses” without a confirmed deficiency is not generally recommended.
- Some people should ask a healthcare professional first
- Extra caution may be needed for people with kidney disease, certain hormone disorders, a history of kidney stones, or those taking medications that affect calcium levels.
- Check the dose
- Many people can meet their needs through sunlight exposure and diet, while others may need supplements based on blood levels and medical advice.
- Be careful with combining supplements
- Vitamin D is often included in multivitamins and calcium supplements, so adding multiple products can unintentionally raise the total dose.
Possible signs of too much vitamin D may include:
- Nausea or vomiting
- Constipation
- Loss of appetite
- Unusual thirst
- Frequent urination
- Weakness or confusion
If you take vitamin D, the safest approach is to use an appropriate dose for your needs and discuss supplementation with a healthcare professional if you are unsure.
If you share the vitamin D dose (for example 1,000 IU, 5,000 IU, or 50,000 IU) and how often you take it, I can help explain whether it is a typical or high dose.
