Caveats: Consider toxicity unlikely
Although excess vitamin D intake, leading to a serum level of 25-hydroxyvitamin D (25[OH]D) >150 ng/mL, can cause toxicity, the IOM has set the tolerable upper intake level of vitamin D (a fat-soluble vitamin stored in the liver) at 2000 IU (50 mcg) for adults and children older than 1 year. Moreover, studies have shown that adults can tolerate doses as high as 10,000 IU per day.4
Symptoms of toxicity include nausea, vomiting, poor appetite, constipation, weakness, and weight loss as well as signs and symptoms of hypercalcemia, including mental status changes, renal failure, and arrhythmias.4
Diseases and drugs that affect serum levels. Patients with mild to moderate renal failure or chronic granulomatous diseases, such as sarcoidosis, are at higher risk of developing vitamin D toxicity. Patients with malabsorption syndromes, mild or moderate hepatic failure, or who take certain medications, like anticonvulsants or glucocorticoids, that increase vitamin D metabolism may need higher doses of vitamin D.9
The good sun. Exposure to sunlight never leads to vitamin D toxicity, as UV radiation destroys any excess vitamin D that is produced.10
Challenges To Implementation: A matter of time
The primary challenge is likely to be the competing demands and limited resources inherent in delivering all preventive health services in the primary care setting. By one estimate, implementing all preventive health services recommended by the US Preventive Services Task Force would require 7.4 hours per day, leaving little if any time to address the acute and chronic care needs of each individual patient.14
PURLs methodology
This study was selected and evaluated using FPIN’s Priority Updates from the Research Literature Surveillance System methodology. The criteria and findings leading to the selection of this study as a PURL can be accessed here.
