ממצאים ממחקרים קליניים מראים הסתברות לכך שצריכת ויטמין D במינון של 10,000 יב"ל/יום לאורך זמן אינה מעלה את הסיכון לתופעות לוואי שליליות כמעט אצל אף אחד באוכלוסייה הכללית. לכן, צריכה ברמה זו ממלאת את הדרישות לקביעת גבול הצריכה המרבי לוויטמין זה.
למאמר מלא על הבטיחות של ויטמין D
Bone Mineral Research. 2007 December
Vitamin D toxicity, policy, and science.
Vieth R.
Source Departments of Nutritional Sciences, and Laboratory Medicine and Pathobiology, University of Toronto, Canada.
Abstract The serum 25-hydroxyvitamin D [25(OH)D] concentration that is the threshold for vitamin D toxicity has not been established. Hypercalcemia is the hazard criterion for vitamin D. Past policy of the Institute of Medicine has set the tolerable upper intake level (UL) for vitamin D at 50 mug (2000 IU)/d, defining this as "the highest level of daily nutrient intake that is likely to pose no risks of adverse health effects to almost all individuals in the general population." However, because sunshine can provide an adult with vitamin D in an amount equivalent to daily oral consumption of 250 mug (10,000 IU)/d, this is intuitively a safe dose. The incremental consumption of (40 IU)/day of vitamin D3 raises serum 25(OH)D by approximately 0.4 ng/ml. Therefore, if sun-deprived adults are to maintain serum 25(OH)D concentrations > 30 ng/ml, they will require an intake of more than the UL for vitamin D... Vitamin D causes hypercalcemia when ... plasma 25(OH)D concentrations become higher than at least 240 ng/ml... The clinical trial evidence shows that a prolonged intake of 10,000 IU/d of vitamin D3 is likely to pose no risk of adverse effects in almost all individuals in the general population; this meets the criteria for a tolerable upper intake level.
This abstract was edited by Dolev Gilmore for clarity and brevity. Those wishing to see the unedited version may do so at PMID: 18290725
