Researchers found the stress of thinking caused overeating with heavy thinkers seeking out more calories.

The research team, supervised by Dr Angelo Tremblay, measured the spontaneous food intake of 14 students after each of three tasks.

The first was relaxing in a sitting position, the second reading and summarizing a text, and finally completing a series of memory, attention, and vigilance tests on the computer.

After 45 minutes at each activity, participants were invited to eat as much as they wanted from a buffet.

The researchers had already discovered that each session of intellectual work requires only three calories more than the rest period.

However, despite the low energy cost of mental work, the students spontaneously consumed 203 more calories after summarizing a text and 253 more calories after the computer tests.

This represents a 23.6 per cent and 29.4 per cent increase, respectively, compared with the rest period.

Blood samples taken before, during, and after each session revealed that intellectual work causes much bigger fluctuations in glucose and insulin levels than rest periods.

Jean-Philippe Chaput, the study's main author, said: "These fluctuations may be caused by the stress of intellectual work, or also reflect a biological adaptation during glucose combustion."

The body could be reacting to these fluctuations by spurring food intake in order to restore its glucose balance, the only fuel used by the brain.

Mr Chaput added: "Caloric overcompensation following intellectual work, combined with the fact we are less physically active when doing intellectual tasks, could contribute to the obesity epidemic currently observed in industrialised countries.

"This is a factor that should not be ignored, considering that more and more people hold jobs of an intellectual nature."

The results of the study, carried out at Universite Laval in Quebec, Canada, are published in the journal Psychosomatic Medicine.

研究人员发现, 思考的压力会导致饮食过量

由安吉罗.川柏雷所领导的研究团队, 针对14位学生在正常三餐以外, 无意识的饮食习性做出上述结论

实验分为三步骤: 首先是放松的闲坐着; 接下来是阅读与汇整资料; 最后是在电脑上完成一系列有关记忆, 注意力与警觉性的测试.

每一步骤进行45分钟, 结束时受测者均可以无限制的随意享用餐点

研究人员发现, 相较于其它两个步骤, 需要动脑筋的步骤仅需多耗约三个卡路里的能量

虽然动脑筋只消耗少量的卡路里, 但学生们却无意识地在汇整资料后多消耗203卡, 而在完成电脑相关测试后多耗了253卡

也就是相较于放松的闲坐, 对于卡路里的需求, 后两个步骤分别增长了23.6%与29.4%

而分别在测试前, 中, 后所做的血液抽样检验也显示, 需要动脑的步骤对于葡萄糖与胰岛素的需求波动远大于其他的步骤.

该实验的主要实施人, 琴-菲利浦. 查普特说: 这种波动可能来自于脑力激荡后所带来的压力, 也可能反映出身体机能在调适上对于葡萄糖的消耗需求变动

我们的身体会因为大脑执行作业而消耗能量, 于是藉由摄取食物以均恒体内葡萄糖的方式来对这种变动采取反应

查普特先生补充: 由于在脑力活动后对于热量的过度补充, 加上在脑力活动时一般很少有相对应的体力消耗, 于是造成现在很多工业化国家中常见的肥胖现象

“这是一项不容忽视的重要因素, 特别是越来越多人从事着脑力活动的工作＂

该项研究报告由加拿大魁北克省Laval大学完成, 并刊载于＂身体与心理医学＂杂志