Dimitrov N V, Meyer C, Ullrey D E, Chenoweth W, Michelakis A, Malone W, Boone C, Fink G
Department of Medicine, Michigan State University, East Lansing.
Am J Clin Nutr. 1988 Aug;48(2):298-304. doi: 10.1093/ajcn/48.2.298.
Normal healthy volunteers were studied after they ingested various beta-carotene doses. Daily administration of 15 or 45 mg beta-carotene resulted in significant increase in plasma beta-carotene levels. The extent of increase and the pattern of plasma beta-carotene levels showed substantial interindividual variation. Absorption of beta-carotene was affected by dietary fat concentration. Individuals placed on a high-fat diet showed significant increases in plasma beta-carotene as compared with those placed on a low-fat diet. Pharmacological doses of beta-carotene (45 and 90 mg) were used in intermittent schedules (5-6 d intervals) without altering the steady state of beta-carotene plasma levels. Yellowing of the skin occasionally occurred during daily dosing with 45 mg beta-carotene without evidence of toxicity. The observed individual variation in bioavailability of beta-carotene raises questions regarding clinical use of this micronutrient. It appears that determination of target plasma beta-carotene concentrations is essential for effective use of this compound in prevention or treatment.
对正常健康志愿者在摄入不同剂量的β-胡萝卜素后进行了研究。每日服用15毫克或45毫克β-胡萝卜素会导致血浆β-胡萝卜素水平显著升高。升高的程度以及血浆β-胡萝卜素水平的模式存在显著的个体间差异。β-胡萝卜素的吸收受膳食脂肪浓度影响。与低脂饮食者相比，高脂饮食者的血浆β-胡萝卜素显著增加。使用药理剂量的β-胡萝卜素（45毫克和90毫克）采用间歇给药方案（间隔5 - 6天），并未改变β-胡萝卜素血浆水平的稳态。每日服用45毫克β-胡萝卜素时偶尔会出现皮肤变黄，但无毒性证据。观察到的β-胡萝卜素生物利用度的个体差异引发了关于这种微量营养素临床应用的问题。看来确定目标血浆β-胡萝卜素浓度对于有效使用该化合物进行预防或治疗至关重要。
