The headline “Pharmacist issues warning to anyone who takes Vitamin D” sounds alarming, but the real message is more specific: vitamin D is important, but taking excessive amounts—especially supplements—can be harmful. (ODS)
What you should know
- Don’t automatically take high doses.
For most adults, the tolerable upper intake level is 4,000 IU (100 micrograms) per day from all sources unless a healthcare professional has prescribed a higher dose for a specific reason. (ODS) - More vitamin D isn’t necessarily better.
Excessive supplementation can cause too much calcium in the blood (hypercalcemia). This can lead to nausea, vomiting, weakness, excessive thirst and urination, dehydration, and kidney stones. Severe toxicity can damage the kidneys and affect heart rhythm. (ODS) - Be careful when combining supplements.
Check multivitamins, calcium supplements and other products to make sure you’re not unknowingly taking vitamin D from several sources. (nhs.uk) - Some medicines can interact with vitamin D.
For example, vitamin D can interact with certain diuretics and digoxin, while some other medicines can alter vitamin D levels. Tell your doctor or pharmacist about all medications and supplements you’re taking. (nhs.uk) - Some people need extra caution.
People with kidney problems, kidney stones, high blood calcium, or conditions that can cause abnormal calcium levels should speak with a healthcare professional before taking vitamin D supplements. (nhs.uk)
The important distinction
This doesn’t mean “never take vitamin D.” Vitamin D deficiency can require supplementation, and doctors sometimes deliberately prescribe higher doses for a limited period. The appropriate dose depends on the individual’s situation. (SPS – Specialist Pharmacy Service)
Bottom line: Don’t take large doses of vitamin D simply because you believe it will provide extra health benefits. If you’re already taking vitamin D, check the strength (IU), how often you take it, and whether you’re also taking calcium or a multivitamin.
