素食会影响你的智力吗?

The vegan diet is low in — or, in some cases, entirely devoid of — several important brain nutrients, argues the BBC. "Could these shortcomings be affecting vegans' abilities to think?"

英国广播公司(BBC)认为:“纯素饮食缺乏几种重要的脑营养素——或者在某些情况下完全缺乏，会影响素食者的思考能力吗?”

According to the latest statistics, there are around 375 million vegetarians on the planet. In the West, veganism has ditched the hippie stigma to become one of the fastest-growing millennial trends; in the United States, it grew by 600% between 2014 and 2017. Meanwhile in India, meat-free diets have been mainstream since the 6th Century BCE...

据最新统计，地球上大约有3.75亿素食者。在西方，纯素食主义已经摆脱了嬉皮的污名，成为增长最快的千禧潮流之一;在美国，这一数字在2014年至2017年间增长了600%。与此同时，在印度，自公元前6世纪以来，无肉饮食已成为主流。

I think we need a lot more research into vegan nutrition and health," says Heather Russell, a dietitian from The Vegan Society. "As far as we can tell, it's possible to lead a healthy life as a vegan — certainly there are people who thrive on a vegan diet." Though it's important to take supplements, she explains that a person's cardiovascular and brain health are inextricably linked, and vegans tend to have healthier hearts...

“我认为我们需要对纯素营养和健康进行更多的研究，”来自纯素协会的营养学家Heather Russell说。“就我所知，作为一个纯素食者过健康的生活是有可能的——当然，有些人是靠纯素食而茁壮成长的。”虽然补充营养很重要，但她解释说，一个人的心血管和大脑健康是密不可分的，素食者往往有更健康的心脏……

Nathan Cofnas, a biologist from Oxford University, takes a harsher view. Though vegans can take supplements, he thinks it's unrealistic to expect that they all will. Consequently, he finds the recent shift towards plant-based diets troubling, though he's sympathetic to the arguments for doing so. "Without question, veganism can cause B12 and iron deficiencies, and without question they affect your intelligence," he says.

牛津大学(Oxford University)生物学家内森•科夫纳斯(Nathan Cofnas)的观点更为严厉。虽然素食者可以补充营养，但他认为期望他们都能补充营养是不现实的。因此，他发现最近向植物性饮食的转变令人不安，尽管他赞同这样做的理由。“毫无疑问，素食会导致B12和铁的缺乏，毋庸置疑，它们一定会影响你的智力。”他说。

The BBC does cite various studies about specific nutrients, but ultimately drew an angry response from a microbiologist who describes themself as "a vegan with a Ph.D., who works alongside many sharp and bright vegans," and complains the BBC is using outdated data, starting with the theory that meat consumption allowed humans to evolve larger brains.

英国广播公司确实引用了各种研究，但最终还是引起了一位微生物学家的愤怒回应。微生物学家称自己为“拥有博士学位的素食主义者，与许多头脑杰出的素食主义者共同工作”，并抱怨英国广播公司使用的是过时的数据，尤其是肉食可以使人类进化出更大的大脑这一老旧理念。

This is now considered outdated thinking as recent research, published in the journal Nature, refutes this, arguing that a higher-quality diet, including some meat but also improved by cooking, coupled with the energy saved by walking upright, growing more slowly and reproducing later, fuelled the growth in brain size. Prehistoric humans ate some meat but that alone didn't make them smart...

最近发表在《自然》(Nature)杂志上的一项研究驳斥了这一观点，认为高质量的饮食(包括一些肉类，但也通过烹饪得到改善)，加上直立行走、生长更慢、繁殖更晚所节省的能量，促进了脑容量的增长。史前人类吃肉，但这并不能使他们变得聪明……

Sure vegans need to ensure a good B12 intake but so should everyone, as low levels of B12 are common in the entire population, regardless of diet. Everyone over 50 in the U.S. is advised to take B12 supplements and meat and dairy only contain it because animals are fed or injected with supplements...

当然，严格的素食者需要确保良好的B12摄入，其实每个人都应该如此，因为低水平的B12在整个人群中很普遍，无论饮食如何。在美国，所有50岁以上的人都被建议服用B12补充剂，或直接食用肉类和奶制品，因为动物饲料中已经添加了B12补充剂…