发现很多家长经常对维生素D的用量有些疑问，花了些时间找到些权威的资料，发帖如下，希望能够给大家一些帮助，特别是针对宝宝，一定要注意。
来自FDA（美国食品和药物管理局）对VD膳食补充剂企业的致信（FDA Letter to Industry Concerning Liquid Vitamin D Dietary Supplements），现对关键部分引用如下:
Most liquid vitamin D products marketed today use a dropper to measure and deliver the vitamin D. FDA has concerns regarding any liquid vitamin D products that could deliver a significantly excessive amount of vitamin D. The concern is that the droppers can hold a considerably greater amount of liquid vitamin D than an infant should receive. This could lead to a parent inadvertently or mistakenly giving an unsafe amount of vitamin D to an infant.
大多数的婴幼儿VD膳食补充剂采用滴管形式来计量，FDA担心这种方式可能会喂给婴儿显著过量（并且是不安全剂量）的维生素D。
To reduce the likelihood of dosing errors, FDA recommends that 400 units be clearly and accurately marked on the dropper accompanying your product. In addition, for products intended for infants, FDA recommends that the dropper hold no more than 400 units.
为减少过量的可能性，FDA建议滴管上应当显著标识400IU的刻度线，并且一次性最多只能吸取400IU的液体VD。
Vitamin D is a generic term that is used to refer to the secosterols, ergocalciferol or Vitamin D2, and cholecalciferol or Vitamin D3 and their metabolites and analogues. Vitamin D is normally produced in the skin from a pro-vitamin using ultraviolet B (UV-B), and with adequate sun exposure, Vitamin D is not required in daily dietary intake. Vitamin D is the principal regulator of calcium, and is therefore important for skeletal development, bone mineralization and bone homeostasis, among other functions.
维生素D是一个通用术语，它是麦角钙化醇（维生素D2），胆钙化甾醇（维生素D3）及其代谢产物和类似衍生物的统称。 人体的皮肤在阳光底下自身就可以合成维生素D，所以当有足够日晒时，人体并不需要补充维生素D。维生素D是钙的主要“监管者”，因此，它对人体的骨骼发育、骨骼矿化、维持骨骼稳定以及其他一些功能中都非常重要。
The Institute of Medicine’s (IOM) recommended Upper Limit (UL) for chronic Vitamin D intake for infants (children less than 1 year of age) is 25 mcg/day (1,000 IU/d), and for children age 1 year and older the recommended UL is 50 mcg/day (2,000 IU/d), based upon the specific vitamin D molecule being D3 from naturally occurring substances, such as fatty fish and fish liver oils. The UL for pregnancy and lactation is the same as for non-pregnant adults at 50 mcg/day (2000 IU/d). The UL value for adults ages 18 and older was based on a safety factor of 1.2 applied to a no adverse effect level (NOAEL) of 60 mcg/d. The lowest adverse effect level (LOAEL) in the IOM analysis was 95 mcg/d. The adverse effect used in the risk assessment was hypercalcemia, serum calcium elevated above the normal range, specified as above 2.75 mmol/liter (11 mg/dL)1.
美国医学研究所建议1岁以下婴幼儿长期摄入维生素D（维生素D3来自于诸如鱼油和鱼肝油等的天然物质）的上限设定为25mcg/天（1000IU/d），1岁以上儿童上限设定为50mcg/天（2000IU/d），孕妇和哺乳的妈咪摄入上限与非怀孕的成年人一样都设定为50mcg/天（2000IU/d），18岁以上成人上限设定值采用NOAEL（无明显损害作用水平，60mcg/d）的1.2倍（安全系数），就是72mcg/天（2880IU/d）.美国医学研究所监测分析到的LOAEL（可观察到的最低有害剂量）为95mcg/天（3800IU/d）。『在美国医学研究所的风险评估中，以发生高钙血症（血钙升高超过正常范围，血钙浓度超过2.75mmol/L）作为摄入过量的判定依据』
In 2008 the American Academy of Pediatrics (AAP) recommended that all breast-fed and partially breast-fed infants (beginning in the first 2 months after birth) consume 400 IU/day of Vitamin D . Initial symptoms of Vitamin D toxicity are usually associated with resultant high serum calcium and include weakness, fatigue, lassitude, headache, nausea, vomiting, and diarrhea; mental status changes and coma may also develop. Renal function may be affected early. Cardiac arrhythmias may also ensue. Prolonged hypercalcemia can lead to soft tissue deposition of calcium; favored areas include the kidney, resulting in other associated problems such as hypertension. Additionally, other soft tissues that are affected include blood vessels, heart, lungs, and skin. Osteomalacia may also occur. Blood chemistry changes include elevated calcium and urea, with inconsistent elevation of phosphorus. If the problem is caught early, treatment may completely reverse the symptoms. Residual sequelae may include permanent renal impairment, and osteoporosis。
2008年，美国儿科学会（AAP）建议，所有母乳喂养、出生后前2个月即开始部分母乳喂养的婴儿应摄入维生素D 400 IU /天。 维生素D中毒的最初症状通常高血钙症相关联，包括虚弱，疲劳，精神不振，头痛，恶心，呕吐，腹泻，精神状态低迷以、昏迷、 早期肾功能会受到影响、 也有可能发生心律失常。 长期高钙血症可导致软组织钙沉积、可影响肾脏、导致其他相关的问题如高血压。 此外，受影响的其它软组织包括血管，心脏，肺和皮肤、也有可能导致软骨病。 血液化学变化包括钙和尿素升高，磷浓度异常等， 如果问题发现得早，可能可以痊愈。 残留的后遗症可能包括永久性肾功能不全和骨质疏松症。
来自FDA（美国食品和药物管理局）对VD膳食补充剂企业的致信（FDA Letter to Industry Concerning Liquid Vitamin D Dietary Supplements），现对关键部分引用如下:
Most liquid vitamin D products marketed today use a dropper to measure and deliver the vitamin D. FDA has concerns regarding any liquid vitamin D products that could deliver a significantly excessive amount of vitamin D. The concern is that the droppers can hold a considerably greater amount of liquid vitamin D than an infant should receive. This could lead to a parent inadvertently or mistakenly giving an unsafe amount of vitamin D to an infant.
大多数的婴幼儿VD膳食补充剂采用滴管形式来计量，FDA担心这种方式可能会喂给婴儿显著过量（并且是不安全剂量）的维生素D。
To reduce the likelihood of dosing errors, FDA recommends that 400 units be clearly and accurately marked on the dropper accompanying your product. In addition, for products intended for infants, FDA recommends that the dropper hold no more than 400 units.
为减少过量的可能性，FDA建议滴管上应当显著标识400IU的刻度线，并且一次性最多只能吸取400IU的液体VD。
Vitamin D is a generic term that is used to refer to the secosterols, ergocalciferol or Vitamin D2, and cholecalciferol or Vitamin D3 and their metabolites and analogues. Vitamin D is normally produced in the skin from a pro-vitamin using ultraviolet B (UV-B), and with adequate sun exposure, Vitamin D is not required in daily dietary intake. Vitamin D is the principal regulator of calcium, and is therefore important for skeletal development, bone mineralization and bone homeostasis, among other functions.
维生素D是一个通用术语，它是麦角钙化醇（维生素D2），胆钙化甾醇（维生素D3）及其代谢产物和类似衍生物的统称。 人体的皮肤在阳光底下自身就可以合成维生素D，所以当有足够日晒时，人体并不需要补充维生素D。维生素D是钙的主要“监管者”，因此，它对人体的骨骼发育、骨骼矿化、维持骨骼稳定以及其他一些功能中都非常重要。
The Institute of Medicine’s (IOM) recommended Upper Limit (UL) for chronic Vitamin D intake for infants (children less than 1 year of age) is 25 mcg/day (1,000 IU/d), and for children age 1 year and older the recommended UL is 50 mcg/day (2,000 IU/d), based upon the specific vitamin D molecule being D3 from naturally occurring substances, such as fatty fish and fish liver oils. The UL for pregnancy and lactation is the same as for non-pregnant adults at 50 mcg/day (2000 IU/d). The UL value for adults ages 18 and older was based on a safety factor of 1.2 applied to a no adverse effect level (NOAEL) of 60 mcg/d. The lowest adverse effect level (LOAEL) in the IOM analysis was 95 mcg/d. The adverse effect used in the risk assessment was hypercalcemia, serum calcium elevated above the normal range, specified as above 2.75 mmol/liter (11 mg/dL)1.
美国医学研究所建议1岁以下婴幼儿长期摄入维生素D（维生素D3来自于诸如鱼油和鱼肝油等的天然物质）的上限设定为25mcg/天（1000IU/d），1岁以上儿童上限设定为50mcg/天（2000IU/d），孕妇和哺乳的妈咪摄入上限与非怀孕的成年人一样都设定为50mcg/天（2000IU/d），18岁以上成人上限设定值采用NOAEL（无明显损害作用水平，60mcg/d）的1.2倍（安全系数），就是72mcg/天（2880IU/d）.美国医学研究所监测分析到的LOAEL（可观察到的最低有害剂量）为95mcg/天（3800IU/d）。『在美国医学研究所的风险评估中，以发生高钙血症（血钙升高超过正常范围，血钙浓度超过2.75mmol/L）作为摄入过量的判定依据』
In 2008 the American Academy of Pediatrics (AAP) recommended that all breast-fed and partially breast-fed infants (beginning in the first 2 months after birth) consume 400 IU/day of Vitamin D . Initial symptoms of Vitamin D toxicity are usually associated with resultant high serum calcium and include weakness, fatigue, lassitude, headache, nausea, vomiting, and diarrhea; mental status changes and coma may also develop. Renal function may be affected early. Cardiac arrhythmias may also ensue. Prolonged hypercalcemia can lead to soft tissue deposition of calcium; favored areas include the kidney, resulting in other associated problems such as hypertension. Additionally, other soft tissues that are affected include blood vessels, heart, lungs, and skin. Osteomalacia may also occur. Blood chemistry changes include elevated calcium and urea, with inconsistent elevation of phosphorus. If the problem is caught early, treatment may completely reverse the symptoms. Residual sequelae may include permanent renal impairment, and osteoporosis。
2008年，美国儿科学会（AAP）建议，所有母乳喂养、出生后前2个月即开始部分母乳喂养的婴儿应摄入维生素D 400 IU /天。 维生素D中毒的最初症状通常高血钙症相关联，包括虚弱，疲劳，精神不振，头痛，恶心，呕吐，腹泻，精神状态低迷以、昏迷、 早期肾功能会受到影响、 也有可能发生心律失常。 长期高钙血症可导致软组织钙沉积、可影响肾脏、导致其他相关的问题如高血压。 此外，受影响的其它软组织包括血管，心脏，肺和皮肤、也有可能导致软骨病。 血液化学变化包括钙和尿素升高，磷浓度异常等， 如果问题发现得早，可能可以痊愈。 残留的后遗症可能包括永久性肾功能不全和骨质疏松症。
