According to a recent large-scale study, taking vitamin D supplements may help ward off dementia. The team of researchers at the University of Calgary in Canada and the University of Exeter in the UK explored the relationship between vitamin D supplementation and dementia in more than 12,388 participants of the US National Alzheimer’s Coordinating Center.

根据最近的一项大规模研究，服用维生素D补充剂可能有助于预防痴呆症。加拿大卡尔加里大学和英国埃克塞特大学的研究团队，在美国国家阿尔茨海默氏症协调中心的12,388名参与者中，探索了维生素D补充剂与痴呆症之间的关系。

The partcipants had a mean age of 71 and were dementia-free when they signed up. Of the group, 37 per cent (4,637) took vitamin D supplements.

参与者的平均年龄为71岁，在他们注册时没有痴呆症。其中37%(4637人)服用了维生素D补充剂。

The study, published in the journal Alzheimer’s & Dementia: Diagnosis, Assessment & Disease Monitoring, found that taking vitamin D was associated with living dementia-free for longer.

这项发表在《阿尔茨海默病与痴呆症:诊断、评估和疾病监测》杂志上的研究发现，服用维生素D与长时间无痴呆症生活有关。

The team also found 40 per cent fewer dementia diagnoses in the group who took supplements. Across the entire sample, 2,696 participants progressed to dementia over ten years; amongst them, 2,017 (75 per cent) had no exposure to vitamin D throughout all visits prior to dementia diagnosis, and 679 (25 per cent) had baseline exposure.

研究小组还发现，在服用补充剂的组中，痴呆症的诊断减少了40%。在整个样本中，2,696名参与者在十年内发展为痴呆;其中2017人(75%)在痴呆症确诊前的所有就诊中没有服用过维生素D，679人(25%)仅入组时服用过维生素D。

“We know that vitamin D has some effects in the brain that could have implications for reducing dementia, however so far, research has yielded conflicting results. Our findings give key insights into groups who might be specifically targeted for vitamin D supplementation. Overall, we found evidence to suggest that earlier supplementation might be particularly beneficial, before the onset of cognitive decline,” said Professor Zahinoor Ismail, of the University of Calgary and University of Exeter, who led the research.

“我们知道维生素D对大脑有一些影响，可能对减少痴呆症有意义，但到目前为止，研究得出的结果都是相互矛盾的。我们的研究结果对那些维生素D补充剂的特定人群至关重要。总而言之，我们发现有证据表明，在认知能力下降之前，早期补充可能特别有益。”领导这项研究的卡尔加里大学和埃克塞特大学的扎希努尔·伊斯梅尔教授说。

While Vitamin D was effective in all groups, the researchers found that effects were significantly greater in females, compared to males.

虽然维生素D对所有组都有效，但研究人员发现，与男性相比，女性的效果明显更大。

Similarly, effects were greater in people with normal cognition, compared to those who reported signs of mild cognitive impairment — changes to cognition which have been linked to a higher risk of dementia.

同样，与那些报告有轻度认知障碍迹象的人相比，认知正常的人的影响更大——认知的变化与痴呆症的高风险有关。

The effects of vitamin D were also significantly greater in people who did not carry the APOEe4 gene, known to present a higher risk for Alzheimer’s dementia, compared to non-carriers.

维生素D对不携带APOEe4基因的人的影响也明显更大，与非携带者相比，携带APOEe4基因的人患阿尔茨海默氏症的风险更高。

Previous research has found that low levels of vitamin D are linked to higher dementia risk. Vitamin D is involved in the clearance of amyloid in the brain, the accumulation of which is one of the hallmarks of Alzheimer’s disease.

先前的研究发现，低水平的维生素D与较高的痴呆症风险有关。维生素D参与大脑中淀粉样蛋白的清除，淀粉样蛋白的积累是阿尔茨海默病的标志之一。

Studies have also found that vitamin D may provide help to protect the brain against build-up of tau, another protein involved in the development of dementia.

研究还发现，维生素D可能有助于保护大脑免受另一种与痴呆症发展有关的蛋白质tau的积累。