Vieth Reinhold, Kimball Samantha, Hu Amanda, Walfish Paul G
Department of Laboratory Medicine and Pathology, University of Toronto, Canada.
Nutr J. 2004 Jul 19;3:8. doi: 10.1186/1475-2891-3-8.
For adults, vitamin D intake of 100 mcg (4000 IU)/day is physiologic and safe. The adequate intake (AI) for older adults is 15 mcg (600 IU)/day, but there has been no report focusing on use of this dose.
We compared effects of these doses on biochemical responses and sense of wellbeing in a blinded, randomized trial. In Study 1, 64 outpatients (recruited if summer 2001 25(OH)D <61 nmol/L) were given 15 or 100 mcg/day vitamin D in December 2001. Biochemical responses were followed at subsequent visits that were part of clinical care; 37 patients completed a wellbeing questionnaire in December 2001 and February 2002. Subjects for Study 2 were recruited if their 25(OH)D was <51 nmol/L in summer 2001. 66 outpatients were given vitamin D; 51 completed a wellbeing questionnaire in both December 2002 and February 2003.
In Study 1, basal summer 25-hydroxyvitamin D [25(OH)D] averaged 48 +/- 9 (SD) nmol/L. Supplementation for more than 6 months produced mean 25(OH)D levels of 79 +/- 30 nmol/L for the 15 mcg/day group, and 112 +/- 41 nmol/L for the 100 mcg/day group. Both doses lowered plasma parathyroid hormone with no effect on plasma calcium. Between December and February, wellbeing score improved more for the 100-mcg/day group than for the lower-dosed group (1-tail Mann-Whitney p = 0.036). In Study 2, 25(OH)D averaged 39 +/- 9 nmol/L, and winter wellbeing scores improved with both doses of vitamin D (two-tail p < 0.001).
The highest AI for vitamin D brought summertime 25(OH)D to >40 nmol/L, lowered PTH, and its use was associated with improved wellbeing. The 100 mcg/day dose produced greater responses. Since it was ethically necessary to provide a meaningful dose of vitamin D to these insufficient patients, we cannot rule out a placebo wellbeing response, particularly for those on the lower dose. This work confirms the safety and efficacy of both 15 and 100 mcg/day vitamin D3 in patients who needed additional vitamin D.
对于成年人而言，每日摄入100微克（4000国际单位）的维生素D是生理所需且安全的。老年人的适宜摄入量（AI）为每日15微克（600国际单位），但尚无关于使用此剂量的报道。
在一项双盲随机试验中，我们比较了这些剂量对生化反应和幸福感的影响。在研究1中，2001年12月，64名门诊患者（如果2001年夏季25(OH)D<61纳摩尔/升则被招募）被给予每日15微克或100微克的维生素D。在作为临床护理一部分的后续就诊中跟踪生化反应；37名患者在2001年12月和2002年2月完成了一份幸福感问卷。如果研究2的受试者在2001年夏季其25(OH)D<51纳摩尔/升，则被招募。66名门诊患者被给予维生素D；51名患者在2002年12月和2003年2月都完成了一份幸福感问卷。
在研究1中，夏季基础25-羟维生素D[25(OH)D]平均为48±9（标准差）纳摩尔/升。补充超过6个月后，每日15微克组的平均25(OH)D水平为79±30纳摩尔/升，每日100微克组为112±41纳摩尔/升。两种剂量均降低了血浆甲状旁腺激素，对血浆钙无影响。在12月至2月期间，每日100微克组的幸福感得分比低剂量组改善得更多（单尾曼-惠特尼检验p=0.036）。在研究2中，25(OH)D平均为39±9纳摩尔/升，两种剂量的维生素D均改善了冬季幸福感得分（双尾p<0.001）。
维生素D的最高适宜摄入量使夏季25(OH)D>40纳摩尔/升，降低了甲状旁腺激素，且其使用与幸福感改善相关。每日100微克的剂量产生了更大的反应。由于从伦理角度有必要向这些维生素D不足的患者提供有意义剂量的维生素D，我们不能排除安慰剂导致的幸福感反应，特别是对于低剂量组的患者。这项工作证实了每日15微克和100微克维生素D3对需要额外维生素D的患者的安全性和有效性。
