Del C Valdés Hernández M, Kyle J, Allan J, Allerhand M, Clark H, Muñoz Manieg S, Royle N A, Gow A J, Pattie A, Corley J, Bastin M E, Starr J M, Wardlaw J M, Deary I J, Combet E
Dr. Maria C. Valdés Hernández, Department of Neuroimaging Sciences, Centre for Clinical Brain Sciences, University of Edinburgh, 49 Little France Crescent, Chancellor's Building, Edinburgh, EH16 4SB, UK. Telephone:+44-131-4659527, Fax: +44-131-3325150, E-mail:
J Nutr Health Aging. 2017;21(9):971-979. doi: 10.1007/s12603-017-0954-8.
Iodine deficiency is one of the three key micronutrient deficiencies highlighted as major public health issues by the World Health Organisation. Iodine deficiency is known to cause brain structural alterations likely to affect cognition. However, it is not known whether or how different (lifelong) levels of exposure to dietary iodine influences brain health and cognitive functions.
From 1091 participants initially enrolled in The Lothian Birth Cohort Study 1936, we obtained whole diet data from 882. Three years later, from 866 participants (mean age 72 yrs, SD±0.8), we obtained cognitive information and ventricular, hippocampal and normal and abnormal tissue volumes from brain structural magnetic resonance imaging scans (n=700). We studied the brain structure and cognitive abilities of iodine-rich food avoiders/low consumers versus those with a high intake in iodine-rich foods (namely dairy and fish).
We identified individuals (n=189) with contrasting diets, i) belonging to the lowest quintiles for dairy and fish consumption, ii) milk avoiders, iii) belonging to the middle quintiles for dairy and fish consumption, and iv) belonging to the middle quintiles for dairy and fish consumption. Iodine intake was secured mostly though the diet (n=10 supplement users) and was sufficient for most (75.1%, median 193 µg/day). In individuals from these groups, brain lateral ventricular volume was positively associated with fat, energy and protein intake. The associations between iodine intake and brain ventricular volume and between consumption of fish products (including fish cakes and fish-containing pasties) and white matter hyperintensities (p=0.03) the latest being compounded by sodium, proteins and saturated fats, disappeared after type 1 error correction.
In this large Scottish older cohort, the proportion of individuals reporting extreme (low vs. high)/medium iodine consumption is small. In these individuals, low iodine-rich food intake was associated with increased brain volume shrinkage, raising an important hypothesis worth being explored for designing appropriate guidelines.
碘缺乏是世界卫生组织强调的三大关键微量营养素缺乏症之一，被视为主要的公共卫生问题。已知碘缺乏会导致大脑结构改变，可能影响认知。然而，尚不清楚不同（终生）水平的膳食碘暴露是否以及如何影响大脑健康和认知功能。
从最初纳入1936年洛锡安出生队列研究的1091名参与者中，我们获取了882人的全膳食数据。三年后，从866名参与者（平均年龄72岁，标准差±0.8）中，我们通过脑结构磁共振成像扫描（n = 700）获得了认知信息以及脑室、海马体以及正常和异常组织体积。我们研究了避免食用富含碘食物/低摄入富含碘食物者（即乳制品和鱼类）与高摄入富含碘食物者的大脑结构和认知能力。
我们确定了饮食情况不同的个体（n = 189），i）乳制品和鱼类消费处于最低五分位数者，ii）不食用牛奶者，iii）乳制品和鱼类消费处于中间五分位数者，以及iv）乳制品和鱼类消费处于中间五分位数者。碘摄入主要通过饮食获得（n = 10名补充剂使用者），并且对大多数人来说是充足的（75.1%，中位数193微克/天）。在这些组的个体中，脑侧脑室体积与脂肪、能量和蛋白质摄入呈正相关。碘摄入与脑室体积之间以及鱼产品（包括鱼饼和含鱼馅饼）消费与白质高信号之间的关联（p = 0.03），后者因钠、蛋白质和饱和脂肪而更为复杂，在进行1类错误校正后消失。
在这个大型苏格兰老年队列中，报告极端（低与高）/中等碘消费的个体比例较小。在这些个体中，低富含碘食物摄入量与脑容量萎缩增加有关，这提出了一个值得在制定适当指南时探索的重要假设。
