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What are the side effects of Vitamin D?

Medically reviewed by Drugs.com. Last updated on Oct 6, 2023.

Official answer

by Drugs.com

Vitamin D has very few side effects when taken at dosages recommended for your age. Side effects are more likely if you take too much vitamin D in the form of supplements, which would then increase your absorption of calcium. These side effects may include:

  • Abnormal heart rhythms
  • Bone pain
  • Confusion or disorientation
  • Constipation
  • High blood calcium levels
  • Kidney stones
  • Muscle weakness or fatigue
  • Nausea
  • Poor appetite
  • Stomach pain.

Vitamin D is an important vitamin for good bone health. It helps with the absorption of calcium and the regulation of other minerals in the body. Without it, bones will become fragile, misshapen and soft, known as rickets in children and osteomalacia in adults. Vitamin D deficiency has also been associated with some cancers, heart disease, depression, and weight gain.

We make vitamin D in our skin when it is exposed to sunlight; however, people who are institutionalized or immobile, spend most of their time indoors, with dark skin, or cover their skin for religious reasons are at risk of vitamin D deficiency.

For more information about vitamin D see here

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Experts cannot say if oral vitamin D helps improve psoriasis symptoms, because overall, trial results have been mixed. While some open-label studies show a moderate to marked improvement (with some reports of remission), most double-blinded RCTs have shown only slight or no improvement. Supplementation could be considered on a case-by-case basis. Continue reading

Generally, it takes a few weeks of taking daily vitamin D supplements for vitamin D levels in the body to rise. Each 1,000 IU of vitamin D3 daily is expected to raise blood levels of 25(OD)D by 10 ng/ml after a few weeks. But it may take months to resolve symptoms of severe vitamin D deficiency such as rickets in children. It depends on how low your vitamin D levels were in the first place and some individual factors. Obesity, polluted environments, and malabsorption syndromes (such as Crohn’s disease) are just some factors that can increase the time it takes for vitamin D levels to work. Continue reading

You can raise your vitamin D levels quickly in three main ways, but it can take up to a week for increased vitamin D intake or exposure to be reflected in a vitamin D blood test: increasing your intake of foods that are naturally rich in vitamin D or fortified with vitamin D, taking a vitamin D supplement, or getting outside and exposing your skin to sunlight (although experts do not recommend this without sun protection). Continue reading

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