还暗搓搓地准备年货囤糖？赶紧刹住，小心变痴呆

In recent years, Alzheimer’s disease has occasionally been referred to as “type 3” diabetes, though that moniker doesn’t make much sense.

近年来，阿尔茨海默症有时被称为“3型糖尿病”，尽管这个绰号没有多大意义。

After all, though they share a problem with insulin, type 1 diabetes is an autoimmune disease, and type 2 diabetes is a chronic disease caused by diet.

毕竟，尽管他们与胰岛素有共同的问题，1型糖尿病是一种自身免疫性疾病，二型糖尿病是由饮食引起的一种慢性疾病。

Instead of another type of diabetes, it’s increasingly looking like Alzheimer’s is another potential side effect of a sugary, Western-style diet.

与另一种类型糖尿病不同的是，越来越多的人认为老年痴呆症是高糖的西式饮食带来的另一隐患。

In some cases, the path from sugar to Alzheimer’s leads through type 2 diabetes, but as a new study and others show, that’s not always the case.

在某些情况下，从糖到老年痴呆症的过程中会引发2型糖尿病，但一项新的研究和其他研究表明，情况并非总是如此。

A longitudinal study, published Thursday in the journal Diabetologia, followed 5,189 people over 10 years and found that people with high blood sugar had a faster rate of cognitive decline than those with normal blood sugar—whether or not their blood-sugar level technically made them diabetic.

周四发表在糖尿病杂志上的一项纵向研究用逾10年时间跟踪调查了5189名试验对象，发现高血糖患者的认知能力下降速度比正常血糖的人快——无论他们的血糖水平是否会使他们患糖尿病。

In other words, the higher the blood sugar, the faster the cognitive decline.

换句话说，血糖越高，认知能力的下降就越快。

“Dementia is one of the most prevalent psychiatric conditions strongly associated with poor quality of later life,” said the lead author, Wuxiang Xie at Imperial College London, via email.

“痴呆症是一种最普遍的精神疾病，它与晚年生活质量的不良关系密切相关，”该研究的主要作者，伦敦帝国理工学院的吴湘西通过电子邮件表示。

“Currently, dementia is not curable, which makes it very important to study risk factors.”

“目前，痴呆症是无法治愈的，这使得研究危险因素变得非常重要。”

Melissa Schilling, a professor at New York University, performed her own reviewof studies connecting diabetes to Alzheimer’s in 2016.

纽约大学教授梅利莎席林在2016年进行了她自己的研究，将糖尿病与阿尔茨海默病联系在一起。

She sought to reconcile two confusing trends.

她试图调和两个令人困惑的趋势。

People who have type 2 diabetes are about twice as likely to get Alzheimer’s, and people who have diabetes and are treated with insulin are also more likely to get Alzheimer’s, suggesting elevated insulin plays a role in Alzheimer’s.

患2型糖尿病的人患老年痴呆症的几率是正常人的两倍，而糖尿病患者和胰岛素治疗的人更容易得老年痴呆症，这表明胰岛素升高在阿尔茨海默病中起着重要作用。

In fact, many studies have found that elevated insulin, or “hyperinsulinemia,” significantly increases your risk of Alzheimer’s.

事实上，许多研究发现，高胰岛素或“高胰岛素血症”会显著增加患老年痴呆症的风险。

On the other hand, people with type 1 diabetes, who don’t make insulin at all, are also thought to have a higher risk of Alzheimer’s.

另一方面，患有1型糖尿病的人，他们根本不生产胰岛素，也被认为患老年痴呆症的风险更高。

How could these both be true?

这两者怎么可能是真的呢？

Schilling posits this happens because of the insulin-degrading enzyme, a product of insulin that breaks down both insulin and amyloid proteins in the brain—the same proteins that clump up and lead to Alzheimer’s disease.

席林认为，这种情况的发生是因为胰岛素降解酶，这种酶是胰岛素的产物，它能分解大脑中的胰岛素和淀粉样蛋白——同样的蛋白质会聚集并导致阿尔茨海默病。

People who don’t have enough insulin, like those whose bodies’ ability to produce insulin has been tapped out by diabetes, aren’t going to make enough of this enzyme to break up those brain clumps.

那些没有足够的胰岛素的人，比如那些身体产生胰岛素的人，已经被糖尿病所利用，他们无法制造足够的这种酶来分解这些大脑块。

Meanwhile, in people who use insulin to treat their diabetes and end up with a surplus of insulin, most of this enzyme gets used up breaking that insulin down, leaving not enough enzyme to address those amyloid brain clumps.

与此同时，在使用胰岛素治疗糖尿病并最终导致胰岛素过剩的人群中，大多数这种酶会耗尽胰岛素，导致没有足够的酶来处理淀粉样脑块。

According to Schilling, this can happen even in people who don’t have diabetes yet—who are in a state known as “prediabetes.”

根据席林的说法，这种情况甚至发生在没有糖尿病的人身上——他们处于一种被称为“糖尿病前期”的状态。

It simply means your blood sugar is higher than normal, and it’s something that affects roughly 86 million Americans.

这仅仅意味着你的血糖高于正常水平，而且它影响了大约8600万美国人。

Schilling is not primarily a medical researcher; she’s just interested in the topic.

席林并不是主要的医学研究者，她只是对这个话题感兴趣。

But Rosebud Roberts, a professor of epidemiology and neurology at the Mayo Clinic, agreed with her interpretation.

但是梅奥诊所的流行病学和神经学教授罗斯巴德罗伯茨同意她的解释。

In a 2012 study, Roberts broke nearly 1,000 people down into four groups based on how much of their diet came from carbohydrates.

在2012年的一项研究中，罗伯茨根据饮食中碳水化合物的摄入量，将近1,000人分成了四组。

The group that ate the most carbs had an 80 percent higher chance of developing mild cognitive impairment—a pit stop on the way to dementia—than those who ate the smallest amount of carbs.

摄入最多碳水化合物的人比那些吃少量碳水化合物的人，患轻度认知障碍的几率要高80%，这是患痴呆症的一个重要节点。

People with mild cognitive impairment, or MCI, can dress and feed themselves, but they have trouble with more complex tasks.

轻度认知障碍的人（简称MCI），可以自己穿衣和吃饭，但他们在处理更复杂的任务时遇到了麻烦。

Intervening in MCI can help prevent dementia.

干预MCI可以帮助预防痴呆。

Rebecca Gottesman, a professor of neurology at Johns Hopkins, cautions that the findings on carbs aren’t as well-established as those on diabetes.

约翰霍普金斯大学的神经学教授Rebecca Gottesman警告说，碳水化合物的发现不如糖尿病患者那么好。

“It’s hard to be sure at this stage, what an ‘ideal’ diet would look like,” she said.

她说：“在这个阶段，很难确定一个理想的饮食是什么样的。”

“There’s a suggestion that a Mediterranean diet, for example, may be good for brain health.”

“例如，有人认为地中海式饮食可能有益于大脑健康。”

But she says there are several theories out there to explain the connection between high blood sugar and dementia.

但她说，有几种理论可以解释高血糖和老年痴呆症之间的联系。

Diabetes can also weaken the blood vessels, which increases the likelihood that you’ll have ministrokes in the brain, causing various forms of dementia.

糖尿病也会使血管变弱，这增加了你在大脑中出现的可能性，导致各种形式的痴呆。

A high intake of simple sugars can make cells, including those in the brain, insulin resistant, which could cause the brain cells to die.

大量的单糖可以使细胞，包括大脑中的细胞，胰岛素抵抗，从而导致脑细胞死亡。

Meanwhile, eating too much in general can cause obesity.

与此同时，吃得太多会导致肥胖。

The extra fat in obese people releases cytokines, or inflammatory proteins that can also contribute to cognitive deterioration, Roberts said.

罗伯茨说，肥胖人群中多余的脂肪会释放出细胞因子，也可能是导致认知能力退化的炎症蛋白。

In one study by Gottesman, obesity doubled a person’s risk of having elevated amyloid proteins in their brains later in life.

Gottesman教授的一项研究表明，肥胖使人在以后的大脑中增加淀粉样蛋白的风险增加了一倍。

Roberts said that people with type 1 diabetes are mainly only at risk if their insulin is so poorly controlled that they have hypoglycemic episodes.

罗伯兹说，1型糖尿病患者的胰岛素如果控制得很差，他们的血糖水平就会降低。

But even people who don’t have any kind of diabetes should watch their sugar intake, she said.

但即使是那些没有任何糖尿病的人也应该注意他们的糖摄入量，她说。

“Just because you don’t have type 2 diabetes doesn’t mean you can eat whatever carbs you want,” she said.

“仅仅因为你没有2型糖尿病，并不意味着你可以吃任何你想要的碳水化合物，”她说。

“Especially if you’re not active.”

“特别是如果你不活跃的话。”

What we eat, she added, is “a big factor in maintaining control of our destiny.”

她补充说，我们吃的东西是“维持我们命运的一个重要因素”。

Roberts said this new study by Xie is interesting because it also shows an association between prediabetes and cognitive decline.

罗伯茨说，谢教授的这项新研究很有趣，因为它也显示了糖尿病前期和认知能力下降之间的联系。

That’s an important point that often gets forgotten in discussions of Alzheimer’s.

这一点在老年痴呆症的讨论中经常被遗忘。

It’s such a horrible disease that it can be tempting to dismiss it as inevitable.

这是一种可怕的疾病，以致于人们认为衰老过程中患阿尔兹海默不可避免。

And, of course, there are genetic and other, non-nutritional factors that contribute to its progression.

当然，还有基因和其他非营养因素会恶化疾病。

But, as these and other researchers point out, decisions we make about food are one risk factor we can control.

但是，正如这些和其他研究人员指出的，我们对食物做出的决定是我们可控范围内的一个风险因素。

And it’s starting to look like decisions we make while we’re still relatively young can affect our future cognitive health.

这看起来就像是我们在相对年轻的时候做出的决定会影响我们未来的认知健康。

“Alzheimer’s is like a slow-burning fire that you don’t see when it starts,” Schilling said.

“阿尔茨海默就像一场即将燎原的星星之火，你一开始看不到它，”席林说。

It takes time for clumps to form and for cognition to begin to deteriorate.

随着时间推移，认知能力开始慢慢退化。

“By the time you see the signs, it’s way too late to put out the fire.”

“当你看到这些迹象的时候，已经病入膏肓为时已晚。”