The study published in the Frontiers in Molecular Neuroscience journal focused on whether and how the diet may influence the brain compared to to stress and other psychological loads during infancy.
The scientists paid special attention to the hippocampus, a brain region responsible for long-term memories, stress regulation and behavioral patterns.
The tests involved female Sprague-Dawley rats (“as females are more likely to experience adverse life events,” the scientists explained) from one litter with half of them being exposed to artificial stressful conditions such as limited nest material for the first days of their life. The other half lived normal rat lives free from stress and anxiety.
During the next stage there were four groups of rodents: a no-stress group drinking water, a no-stress group drinking sugar solution, a stress group drinking water and a stress group drinking sugar solution.
The experiment took 15 weeks and ended with a check of the rats’ brains. The autopsy showed similar anomalies in the hippocampus regions both in the rats that were stressed but drank water and the non-stressed rats that drank sugar. The receptor hindering the stress hormone cortisol was found impaired which means coping with stress for those rats wouldn’t be that easy.
“The novelty of this study lies in the finding that chronic consumption of sugar produced equivalent hippocampal molecular deficits as early life stress exposure,” the study said.
Both sugar and stress also messed with a gene, called Neurod1 that is accountable for the growth of nerves. Other similar genes were affected only by sugar, the study noted.
However, it’s still not clear whether similar processes take place in human bodies as well, and so further research is required, the scientists said.
The results raise a major issue since the diet of an average modern human often includes sugary soft drinks.
“If similar processes are at play in humans, manipulating the later environment of those exposed to early life adversity, and controlling the consumption of sugar-sweetened beverages across the community may be an effective way to curtail the burden of psychiatric disorders,” the study explained.