Ribaya-Mercado Judy D, Solon Florentino S, Fermin Liza S, Perfecto Christine S, Solon Juan Antonio A, Dolnikowski Gregory G, Russell Robert M
Jean Mayer US Department of Agriculture Human Nutrition Research Center on Aging at Tufts University, Boston, MA 02111, USA.
Am J Clin Nutr. 2004 Apr;79(4):633-41. doi: 10.1093/ajcn/79.4.633.
The vitamin A requirements of elderly humans have not been studied.
In a cross-sectional study of 60-88-y-old men (n = 31) and women (n = 31) in rural Philippines, we assessed the dietary intakes of elders with adequate (> or = 0.07 micromol/g) or low (< 0.07 micromol/g) liver vitamin A concentrations to estimate vitamin A requirements for this age group.
Total-body vitamin A was assessed by the deuterated-retinol-dilution technique; liver vitamin A concentrations were assessed by assuming that liver weight is 2.4% of body weight and that, in this marginally nourished population, 70% of total-body vitamin A is in the liver; serum retinol was measured by HPLC; and dietary intakes were assessed with 3 nonconsecutive 24-h dietary recalls. The mean vitamin A intake + 2 SDs of subjects with adequate liver vitamin A concentrations was used to estimate an acceptable or sufficient vitamin A intake value for elders.
The mean (+/- SD) vitamin A intakes of the men and women with adequate vitamin A in liver were 135 +/- 86 and 134 +/- 104 microg retinol activity equivalents (RAE)/d, respectively; intakes of the men and women with low vitamin A in liver were 75 +/- 53 and 60 +/- 27 microg RAE/d, respectively. Total-body vitamin A or liver vitamin A but not serum retinol correlated with dietary RAE, preformed vitamin A, beta-carotene, fat, and protein. An estimated acceptable or sufficient dietary vitamin A intake associated with adequate liver vitamin A concentrations in elders is 6.45 microg RAE/kg body wt; for a reference 76-kg man and a 61-kg woman, these values are approximately 500 and 400 microg RAE/d, respectively.
The dietary vitamin A intakes of elders with adequate or low liver vitamin A concentrations as estimated by use of the deuterated-retinol-dilution technique are useful for assessing vitamin A requirements.
尚未对老年人的维生素A需求进行研究。
在一项针对菲律宾农村地区60至88岁男性（n = 31）和女性（n = 31）的横断面研究中，我们评估了肝脏维生素A浓度充足（≥0.07微摩尔/克）或较低（<0.07微摩尔/克）的老年人的膳食摄入量，以估算该年龄组的维生素A需求。
采用氘代视黄醇稀释技术评估全身维生素A；假设肝脏重量占体重的2.4%，且在这个营养状况稍差的人群中，全身维生素A的70%存在于肝脏中，据此评估肝脏维生素A浓度；通过高效液相色谱法测定血清视黄醇；采用3次非连续的24小时膳食回顾评估膳食摄入量。肝脏维生素A浓度充足的受试者的平均维生素A摄入量加2个标准差，用于估算老年人可接受或充足的维生素A摄入量值。
肝脏维生素A充足的男性和女性的平均（±标准差）维生素A摄入量分别为135±86和134±104微克视黄醇活性当量（RAE）/天；肝脏维生素A较低的男性和女性的摄入量分别为75±53和60±27微克视黄醇活性当量/天。全身维生素A或肝脏维生素A与膳食视黄醇活性当量、预形成的维生素A、β-胡萝卜素、脂肪和蛋白质相关，但与血清视黄醇无关。与老年人肝脏维生素A浓度充足相关的估计可接受或充足的膳食维生素A摄入量为6.45微克视黄醇活性当量/千克体重；对于参考体重76千克的男性和61千克的女性，这些值分别约为500和400微克视黄醇活性当量/天。
通过氘代视黄醇稀释技术估算的肝脏维生素A浓度充足或较低的老年人的膳食维生素A摄入量，有助于评估维生素A需求。
