Department of Nutrition and Food Hygiene, The National Key Discipline, School of Public Health, Harbin Medical University, Harbin, PR China.
Department of Nutrition and Food Hygiene, The National Key Discipline, School of Public Health, Harbin Medical University, Harbin, PR China.
Clin Nutr. 2021 Apr;40(4):2401-2409. doi: 10.1016/j.clnu.2020.10.038. Epub 2020 Oct 23.
BACKGROUND & AIMS: Although disorders of iron metabolism are among the most common diseases and dietary intakes of vitamin A, B, B, C, E, and folic acid are known to affect the absorption or oxidation of iron, limited data are available on the association of dietary iron and these vitamins with mortality in the same population. Specifically, the holistic dietary vitamins intake and its combined effect with iron on mortality are unclear. The purpose of this study was to evaluate the association of dietary iron, holistic dietary vitamins, and their interactive effect with total and cause-specific mortality.
We evaluated the effects of dietary total/heme/non-heme iron, vitamins, and their interaction on all-cause/cardiovascular disease (CVD)/cancer mortality among 14,826 US adults in the National Health and Nutrition Examination Survey (NHANES), a population-based nationally representative study. We developed a vitamin score to represent the holistic dietary intakes of vitamin A, B, B, C, E, and folic acid.
A total of 2154 deaths occurred during a median follow-up of 9.3 years. Results from multivariate Cox proportional hazards models showed that higher vitamin score was associated lower risk of all-cause mortality (P-trend = 0.027). Negative interactions between dietary heme iron and vitamin score were observed on all-cause/CVD mortality. Dietary higher vitamins combined with lower heme iron was associated with lower risk of all-cause and CVD mortality (HR (95% confidence intervals (CIs)): 0.80 (0.64-0.98) and 0.55 (0.31-0.98), respectively). Higher dietary vitamins combined with higher total/non-heme iron was associated with lower risk of CVD mortality (HR (95%CIs): 0.69 (0.48-0.99) and 0.70 (0.48-0.99), respectively). These results remained significant even excluding participants with iron supplementation.
Our findings suggested that interactive effect of holistic dietary vitamins and iron play a protective role in decreasing all-cause and CVD mortality. Future studies, including cohort studies and clinical trials, are necessary to confirm these findings.
尽管铁代谢紊乱是最常见的疾病之一，并且人们已知维生素 A、B、B、C、E 和叶酸的膳食摄入量会影响铁的吸收或氧化，但关于同一人群中铁与这些维生素的膳食摄入量与死亡率之间的关联，数据有限。具体来说，整体膳食维生素的摄入量及其与铁的综合作用对死亡率的影响尚不清楚。本研究旨在评估膳食铁、整体膳食维生素及其与总死亡率和死因特异性死亡率的交互作用。
我们评估了膳食总铁/血红素铁/非血红素铁、维生素及其相互作用对美国国家健康与营养调查（NHANES）中 14826 名美国成年人全因/心血管疾病（CVD）/癌症死亡率的影响，这是一项基于人群的具有全国代表性的研究。我们开发了一个维生素评分来代表维生素 A、B、B、C、E 和叶酸的整体膳食摄入量。
在中位随访 9.3 年期间，共发生 2154 例死亡。多变量 Cox 比例风险模型的结果表明，较高的维生素评分与全因死亡率降低相关（P 趋势=0.027）。膳食血红素铁与维生素评分之间存在负交互作用，与全因/CVD 死亡率有关。较高的膳食维生素与较低的血红素铁相结合与全因和 CVD 死亡率降低相关（HR（95%置信区间（CI））：0.80（0.64-0.98）和 0.55（0.31-0.98））。较高的膳食维生素与较高的总/非血红素铁相结合与 CVD 死亡率降低相关（HR（95%CI）：0.69（0.48-0.99）和 0.70（0.48-0.99））。即使排除了接受铁补充剂的参与者，这些结果仍然具有统计学意义。
我们的研究结果表明，整体膳食维生素和铁的相互作用在降低全因和 CVD 死亡率方面发挥了保护作用。未来的研究，包括队列研究和临床试验，有必要证实这些发现。
