Department of Nutrition, Faculty of Medicine, University of Chile, Santiago, Chile.
Am J Clin Nutr. 2011 Oct;94(4):1004-11. doi: 10.3945/ajcn.111.018143. Epub 2011 Aug 24.
Micronutrient deficiencies are common in patients undergoing gastric bypass. The effect of this type of surgery on zinc absorption and zinc status is not well known.
The objective was to evaluate the effects of Roux-en-Y gastric bypass (RYGBP) on zinc status and zinc absorption at different stages after surgery. We hypothesized that zinc status would be significantly impaired after surgery and that this impairment would be less severe in subjects receiving increased supplemental zinc. We also hypothesized that zinc absorption would be lower after surgery.
Anthropometric and body-composition variables and dietary and biochemical indexes of zinc status and zinc absorption were determined in 67 severe and morbidly obese women [mean (±SD) age: 36.9 ± 9.8 y; BMI (in kg/m(2)): 45.2 ± 4.7] who underwent RYGBP. The subjects were randomly assigned to 1 of 2 vitamin-mineral supplementation groups. Measurements were made before and 6, 12, and 18 mo after surgery. Fifty-six subjects completed the 18-mo follow-up.
Mean plasma zinc, erythrocyte membrane alkaline phosphatase activity, and the size of the rapidly exchangeable zinc pool decreased after RYGBP. Percentage zinc absorption decreased significantly from 32.3% to 13.6% at 6 mo after RYGBP and to 21% at 18 mo after surgery. No effect of supplement type was observed.
Zinc status is impaired after RYGBP, despite the finding that dietary plus supplemental zinc doubled recommended zinc intakes in healthy persons. Zinc absorption capacity is significantly reduced soon after RYGBP, with no major changes until 18 mo after surgery.
接受胃旁路手术的患者常存在微量营养素缺乏。此类手术对锌吸收和锌状态的影响尚不清楚。
本研究旨在评估胃旁路术后不同阶段对锌状态和锌吸收的影响。我们假设手术后锌状态会显著受损，且补充更多锌的患者受损程度会较轻。我们还假设手术后锌吸收会降低。
对 67 例严重和病态肥胖女性（平均年龄为 36.9 ± 9.8 岁；BMI[kg/m²]：45.2 ± 4.7）进行人体测量和身体成分变量以及膳食和生化指标的锌状态和锌吸收的评估，这些女性均接受了 Roux-en-Y 胃旁路术（RYGBP）。将受试者随机分配到 2 种维生素-矿物质补充组中的 1 种。分别于术前及术后 6、12 和 18 个月进行测量。56 例受试者完成了 18 个月的随访。
RYGBP 后，平均血浆锌、红细胞膜碱性磷酸酶活性和快速交换锌池的大小降低。术后 6 个月时，锌吸收率从 32.3%显著降至 13.6%，术后 18 个月时降至 21%。未观察到补充类型的影响。
尽管膳食加补充锌使健康人群的锌摄入量增加了两倍，但 RYGBP 后锌状态仍会受损。RYGBP 后不久，锌吸收能力显著降低，直到术后 18 个月才出现较大变化。
