08 April 2015 - MNT - Critical windows to turn away junk food craving

This work leads on from earlier findings which showed that mothers who eat junk food while pregnant are programming their babies to be addicted to a high fat, high sugar diet by the time they are weaned.

Their latest laboratory studies reveal there may be a chance to turn around this junk food addiction in two critical windows--equating to late pregnancy and in adolescence in humans.

"Our research suggests that too much junk food consumed late in pregnancy for humans has the potential to be more harmful to the child than excess junk food early in the pregnancy," says Dr Jessica Gugusheff, post-doctoral researcher in the School of Agriculture, Food and Wine.

"Importantly, it also indicates that if excess junk food was consumed by the mother in those early stages of pregnancy, there may be a chance to reduce those negative effects on the baby by eating a healthy diet in late pregnancy.

"The second critical window is adolescence and we've found differences between males and females. Our experiments showed that eating a healthy diet during adolescence could reverse the junk-food preference in males but not females."

The junk food preference is believed to result from a desensitisation of the normal reward system (the opioid and dopamine signalling pathway) fuelled by highly palatable high fat, high sugar diets. Offspring with less sensitive reward systems need more fat and sugar to get the same "good feeling".