Raw fruits and vegetables may be better for your mental health than cooked ones, according to a new study from the University of Otago in New Zealand. The study, published in Frontiers in Psychology¹, found that people who ate more uncooked produce had lower levels of symptoms related to depression and other mental illnesses, compared to those who ate more cooked, canned, or processed varieties.

新西兰奥塔哥大学的一项新研究表明：生的水果和蔬菜或许比煮熟的水果和蔬菜更有益于心理健康。这篇研究发表在Frontiers in Psychology期刊上，研究发现：与那些经常吃煮熟的、罐装或处理过的农产品的人相比，经常吃生的农产品的人患抑郁症和其它心理疾病的风险更低。

The study was only able to show an association between raw produce and better mental health, not a cause-and-effect relationship. But the researchers say the link could have to do with the fact that many fruits and vegetables have more nutrients² in their natural state-and that those nutrients may have a positive impact on mood and brain chemistry.

这项研究只能表明生的农产品和更佳的心理健康之间存在联系，却不能证明是因果关系。但研究员表示，这种联系可能与这一事实相关：很多水果和蔬菜在其自然状态下有更多的营养成分--而这些营养成分可能对心情和大脑有积极作用。

For the study, researchers surveyed more than 400 young adults, ages 18 to 25, in the United States and New Zealand. People in this age group tend to consume a relatively³ low level of fruits and vegetables, the authors point out, and are also at high risk for mental health disorders⁴.

这项研究涉及了美国和新西兰400多位年轻人，年龄为18至25岁。研究作者指出，这个年龄段的人群往往摄入相对较少的水果和蔬菜，同时患心理健康障碍的风险也较高。

The participants were asked about their typical consumption of fruits and vegetables, including which specific varieties they ate and how the produce was prepared. They were also screened for symptoms of mental illnesses, like depression and anxiety.

研究员问了受试者摄入水果和蔬菜的一般情况，包括他们吃哪种类型的水果和蔬菜，如何摄入这些农产品。同时对他们进行了筛查，筛查他们心理疾病的症状，比如抑郁和焦虑。

The study authors knew that plenty of other variables could influence both mental health and fruit and vegetable consumption. So they also made sure to consider participants' exercise habits, overall diet, existing health conditions, socioeconomic status, ethnicity, and gender⁵.

研究作者知道很多其它变量也会影响心理健康和水果蔬菜的摄入量。所以他们也会考虑受试者的锻炼习惯、整体饮食、现有的健康状况、社会经济状况、种族和性别。

Even after controlling for those lifestyle and demographic factors, the association between raw vegetables and positive mental health outcomes was significant. Raw fruit and vegetable consumption predicted lower levels of depression and improved levels of psychological well-being⁶, the authors wrote, including positive mood and life satisfaction.

即使控制这些生活方式和人口因素之后，生蔬菜和积极的心理健康之间的关系也是十分显著的。作者写道，预计生水果和蔬菜的摄入能降低抑郁程度，提高人们的心理健康，包括情绪高涨和生活满足感。

By contrast, intake⁷ of fruit and vegetables that were processed (by cooking, canning, or other methods) was associated only with positive mood-not with any of the other mental health variables measured in the study.

相较之下，摄入处理过的水果和蔬菜（烹饪、罐装或其它方法）只与心情变好一点点相关--本研究没有控制其它影响心理健康的因素。

Overall, the 10 foods in the study that were most strongly associated with positive mental-health outcomes were carrots, bananas, apples, dark leafy greens (such as spinach), grapefruit, lettuce⁸, citrus fruits, fresh berries, cucumber, and kiwifruit.

总的来说，研究强烈建议食用这10种与积极的心理健康结果最为密切相关的食物：胡萝卜、香蕉、苹果、深色绿叶蔬菜（如菠菜）、葡萄柚、莴苣、柑橘类水果、新鲜浆果、黄瓜和猕猴桃。