Cholecalciferol (vitamin D3) at high daily doses in hospital patients
What it found
In over 4700 hospital patients, daily vitamin D3 doses from 5000 to 50,000 international units produced no cases of high blood calcium or other side effects tied to the supplement.
Three patients with psoriasis saw their skin improve markedly on 20,000 to 50,000 international units a day.
What they found
Studies in people
No high calcium seen
There were no cases of high blood calcium caused by vitamin D3 and no side effects attributed to the supplement in any patient.
Psoriasis skin improvement
Three patients with psoriasis showed marked clinical improvement in their skin while taking 20,000 to 50,000 international units a day.
Deficiency common without D3
Among 777 recently tested patients not taking vitamin D3, 28.7% had blood levels of 25-hydroxyvitamin D3 below 20 ng/ml and 64.1% were below 30 ng/ml. Their average level was 27.1 ng/ml, ranging from 4.9 to 74.8 ng/ml.
Blood levels on D3
In 418 patients taking vitamin D3 long enough to reach blood levels above 74.4 ng/ml, the average 25-hydroxyvitamin D3 level was 118.9 ng/ml, with a range from 74.4 to 384.8 ng/ml.
Calcium and parathyroid
The average blood calcium was 9.5 mg/dl without vitamin D3 and 9.6 mg/dl with it, after excluding patients with other causes of high calcium. Average parathyroid hormone was 24.2 pg/ml on vitamin D3 and 30.2 pg/ml without it.
What the authors conclude
“In summary, long-term supplementation with vitamin D3 in doses ranging from 5000 to 50,000 IUs/day appears to be safe.”
Also in their conclusions
- They conclude that long-term supplementation with vitamin D3 in doses ranging from 5000 to 50,000 IUs/day appears to be safe.
How it was done
Vitamin D deficiency is common because people do not get enough sun and because very few foods contain vitamin D. The authors note that deficiency is strongly linked to higher risk of many diseases, some of which have improved with adequate UVB exposure or with vitamin D supplements.
All patients admitted to their hospital were screened for vitamin D deficiency from July 2011 and offered supplements. Over 4700 patients were admitted during this time, most agreeing to 5000 or 10,000 international units a day, and a few taking 20,000 to 50,000 international units a day because of other health concerns.
What it can’t tell you
- We summarised it from the abstract only.
- This was a hospital programme, not a randomised trial, so it cannot prove that vitamin D3 caused the improvements seen in the three psoriasis patients.
- The findings come from patients at one hospital and may not apply to other groups of people.
Who paid
- Authors work at
- Wright State University School of Medicine, United States
The paper
- Title
- Daily oral dosing of vitamin D3 using 5000 TO 50,000 international units a day in long-term hospitalized patients: Insights from a seven year experience
- Type
- Study
- Evidence
- Studies in people
- Summarised from
- Abstract only
- Cite
- McCullough PJ, Lehrer DS, Amend J (2019). Daily oral dosing of vitamin D3 using 5000 TO 50,000 international units a day in long-term hospitalized patients: Insights from a seven year experience. The Journal of steroid biochemistry and molecular biology. doi:10.1016/j.jsbmb.2018.12.010PubMed 30611908DOI
Summary written 26 Sep 2026. Check it against the paper before it changes what you eat. How we summarise papers · Report an error