Babies of women who eat junk food while pregnant 'more likely to be obese' The study, published in the FASEB journal, found babies of junk food eating mothers have less sensitivity to opioids and are more likely to overeat junk food, even in adulthood. It is the first time scientists have demonstrated the long-term impact of maternal junk food consumption during pregnancy and breastfeeding. Dr Bev Mühlhäusler, from Adelaide University, said the mothers who ate junk food impeded the baby's ability to respond to opioids and forced the child to eat more sugar and fat to achieve a "good feeling." "We found that the opioid signalling pathway (the reward pathway) in these offspring was less sensitive than those whose mothers were eating a standard diet," she said. This means that children being born to a mother who ate a diet dominated by junk food would need to eat more fat and sugar to get the same good feeling, increasing their preference for junk food. It would also encourage them to overeat. Dr Mühlhäusler said junk food babies will find it "permanently" harder to achieve a healthy body weight. "Mothers eating a lot of junk food while pregnant are setting up their children to be addicted," she said. [Although] many of the long-term health problems associated with maternal junk food diets can be avoided if offspring carefully follow a healthy diet after weaning, they are always going to have a predisposition for overconsumption of junk food and obesity. The study examined the impact of eating foods such as peanut butter, sugary breakfast foods, nutella and lard. It said the results showed the impact of junk food on a baby's reward pathways and highlighted the need for further research on mothers' diets to address rising obesity rates. "A better understanding of this mechanism is crucial if we are to develop possible strategies for intervention and becomes increasingly important in view of the rapidly rising rates of both childhood and adult obesity," it said.