Sleep restriction increases the neuronal response to unhealthy food in normal-weight individuals.

International journal of obesity (2005). 2014;38(3):411-6

Plain language summary

Sleep patterns influence eating behaviour and the body’s response to food. Previous studies suggest that short sleep duration leads to increased caloric intake and a desire for high-fat foods, however the specific neural mechanisms explaining how sleep restriction modulates this response is unknown. The aim of this study was to determine whether a specific area of the brain is activated in response to unhealthy compared with healthy foods. 25 participants were included, all of which were normal weight and had normal sleeping patterns. Each participant was tested after five nights of either 4 or 9 hours in bed by functional magnetic resonance imaging (fMRI). The test was performed while the participant was shown healthy and unhealthy food photos in the fasted state. This study found that after a period of restricted sleep compared with habitual sleep, unhealthy foods led to greater activation in brain regions associated with reward compared with healthy foods. This finding provides a model of neuronal mechanisms relating short sleep duration to obesity and cardio-metabolic risk factors and warrants further investigation.

Abstract

CONTEXT Sleep restriction alters responses to food. However, the underlying neural mechanisms for this effect are not well understood. OBJECTIVE The purpose of this study was to determine whether there is a neural system that is preferentially activated in response to unhealthy compared with healthy foods. PARTICIPANTS Twenty-five normal-weight individuals, who normally slept 7-9 h per night, completed both phases of this randomized controlled study. INTERVENTION Each participant was tested after a period of five nights of either 4 or 9 h in bed. Functional magnetic resonance imaging (fMRI) was performed in the fasted state, presenting healthy and unhealthy food stimuli and objects in a block design. Neuronal responses to unhealthy, relative to healthy food stimuli after each sleep period were assessed and compared. RESULTS After a period of restricted sleep, viewing unhealthy foods led to greater activation in the superior and middle temporal gyri, middle and superior frontal gyri, left inferior parietal lobule, orbitofrontal cortex, and right insula compared with healthy foods. These same stimuli presented after a period of habitual sleep did not produce marked activity patterns specific to unhealthy foods. Further, food intake during restricted sleep increased in association with a relative decrease in brain oxygenation level-dependent (BOLD) activity observed in the right insula. CONCLUSION This inverse relationship between insula activity and food intake and enhanced activation in brain reward and food-sensitive centers in response to unhealthy foods provides a model of neuronal mechanisms relating short sleep duration to obesity.

Lifestyle medicine

Fundamental Clinical Imbalances : Hormonal ; Neurological
Patient Centred Factors : Mediators/Sleep
Environmental Inputs : Diet ; Nutrients
Personal Lifestyle Factors : Nutrition ; Sleep and relaxation
Functional Laboratory Testing : Imaging

Methodological quality

Allocation concealment : Yes

Metadata

Nutrition Evidence keywords : BMI ; Sleep duration ; Insular cortex ; Overeating