Lack of effect of short-term fasting on cognitive function.

In a study designed to assess the effects of short-term food deprivation on cognitive function, a sample of female subjects (N = 21) was tested on a number of measures of cognitive function after three levels of food deprivation (miss one meal, miss two meals or miss all food for 24 h prior to testing) and a condition in which they ate normally for 24 h prior to testing. There was found to be no significant effects of food deprivation on sustained attention, attentional focus, simple reaction time or immediate memory. However, performance on a low processing load tapping task was significantly poorer when the subjects were deprived of food for 24 h prior to testing, and heart rate was significantly higher when they were non-deprived. These results stand in contrast to the impairments in cognitive function previously found to be associated with spontaneous dieting behaviour (using essentially the same task battery).