Australasian Science: Australia's authority on science since 1938

Poor Maternal Nutrition Primes Child Obesity

By Stephen Luntz

Rats whose mothers were fed an unhealthy diet during pregnancy need more junk food to get the same hit, according to research published in FASEB. The mechanism appears to be a shortage of pleasure receptors in the brain.

Jessica Gugusheff, a PhD student at the University of Adelaide’s FoodPlus Research Centre, gave one group of rats a healthy diet both during pregnancy and while the young were suckling, while another group was given a diet high in sugar, salt and fat. She found that genes for endogenous opioids were suppressed in the offspring whose mothers were fed the unhealthy diet.

Gugusheff gave both sets of juvenile rats an opioid receptor blocker that prevents the effects of heroin, and then offered them a junk food meal. The rats with the healthy mothers ate less of this meal, apparently because they could get their pleasure reward while consuming fewer calories.

However, opioid receptor blockers would be a problematic form of weight control. “By blocking the reward pathway, the drug can increase depression,” Gugusheff says before hurriedly adding that the doses she gave the rats wore off quickly. “So they were only unhappy for 2 hours.”

Gugusheff says her work is “only at the early stages,” but thinks the release of opioids in the brains of the pregnant mothers affects the formation of receptors in the offspring.

While mothers today are bombarded with more advice than ever before about what they should eat during pregnancy, Gugusheff says evidence that half of South Australian mothers are overweight when they become pregnant suggests that their diets are probably unhealthy, and this may be contributing to the rise in childhood obesity.

Gugusheff has won the 2013 Young Investigator Award for South Australia’s leading young scientist.