Herrero-Barbudo Carmen, Olmedilla-Alonso Begoña, Granado-Lorencio Fernando, Blanco-Navarro Inmaculada
Servicio de Endocrinología y Nutrición Unidad de Vitaminas, Hospital Universitario Puerta de Hierro, C/ San Martín de Porres 4, 28035 Madrid, Spain.
Eur J Nutr. 2006 Oct;45(7):391-8. doi: 10.1007/s00394-006-0612-0. Epub 2006 Sep 28.
Dairy products fortified with vitamins and minerals represent a growing market that is of interest to those sectors of the population with unbalanced diets and increased needs. However, there is little information on the bioavailability of micronutrients in milk products at dietary intake levels.
To evaluate the bioavailability of vitamins A and E in whole milk and fortified whole and skimmed milk in control subjects.
A single-dose bioavailability study was performed using three commercially available milks (unfortified whole milk and whole and skimmed milk fortified with vitamins A and E). Nineteen volunteers (10 women and 9 men) ingested 430 ml of each milk on different days. The contents of retinol and alpha-tocopherol provided in the milks and the retinyl esters and alpha-tocopherol in triglyceride-rich lipoprotein fractions (TRL) from plasma collected for 6.5 h postprandially were assayed using a quality-controlled HPLC method. The relative absorption of vitamins A and E from milks was calculated on the basis of area under the curve (AUC) versus time curve estimations, adjusted for plasma volume and expressed as percentage of the amount of nutrient provided.
The total amounts of retinol and alpha-tocopherol provided ranged between 0.48 and 4.15 micromol and 0.41 and 32.49 micromol, respectively. The AUC value of retinyl palmitate in TRL was higher for fortified whole milk than for the other two milks (unfortified whole and fortified skimmed milk). The percent relative absorption of vitamin A did not differ among the three types of milk. The AUC for alpha-tocopherol was no different after the ingestion of any of these milks.
The mean percentage of retinol absorption was apparently similar for the three types of milk, regardless of the amount of fat ingested with each type of milk and the vitamin A provided.
添加了维生素和矿物质的乳制品市场不断增长，这对于饮食不均衡及需求增加的人群具有吸引力。然而，关于膳食摄入水平下乳制品中微量营养素生物利用度的信息却很少。
评估对照人群中全脂牛奶以及强化全脂和脱脂牛奶中维生素A和E的生物利用度。
采用单剂量生物利用度研究，使用三种市售牛奶（未强化的全脂牛奶以及强化了维生素A和E的全脂和脱脂牛奶）。19名志愿者（10名女性和9名男性）在不同日期分别摄入430毫升每种牛奶。采用质量控制的高效液相色谱法测定牛奶中视黄醇和α-生育酚的含量，以及餐后6.5小时收集的血浆中富含甘油三酯的脂蛋白组分（TRL）中的视黄酯和α-生育酚含量。根据曲线下面积（AUC）与时间曲线估计值计算牛奶中维生素A和E的相对吸收率，并根据血浆体积进行调整，以提供的营养素量的百分比表示。
视黄醇和α-生育酚的提供总量分别在0.48至4.15微摩尔和0.41至32.49微摩尔之间。强化全脂牛奶中TRL中棕榈酸视黄酯的AUC值高于其他两种牛奶（未强化的全脂牛奶和强化脱脂牛奶）。三种类型牛奶中维生素A的相对吸收百分比没有差异。摄入任何一种牛奶后，α-生育酚的AUC没有差异。
三种类型的牛奶中视黄醇吸收的平均百分比显然相似，无论每种牛奶摄入的脂肪量以及提供的维生素A如何。
