Effects of glucose and sucrose on mood: a systematic review of interventional studies.

Context: Glucose is the main energy source for the brain, and as such, manipulation of glucose supply may affect brain function. It has been suggested that a change in blood glucose may influence mood. Objective: The aim of this review was to investigate the potential effects of glucose and sucrose, compared with placebo, on mood. Data Sources: The electronic databases PubMed and Scopus were searched. Reference lists of selected articles were checked manually. Data Extraction: Randomized controlled trials or crossover trials comparing the effects of glucose or sucrose on mood that were published up to May 2017 were eligible. Potentially eligible articles were selected independently by 2 reviewers. Results: In total, 19 studies were found. Thirteen studies investigated the effects of glucose consumption compared with placebo on mood. Seven of these 13 studies found no effect of glucose on mood. The other 6 studies found small and partial effects that may also be due to other factors like palatability and expectation. Seven of the 19 studies investigated the effects of sucrose ingestion versus placebo on mood. None of these studies found a positive effect on mood, and 1 study observed an adverse effect. One of the studies investigated the effects of both glucose and sucrose. Conclusions: The results from this review show limited effects of glucose ingestion on mood and no effect of sucrose on mood.