Because this is an early study, UCLA researchers do not recommend that mothers of low-birth weight infants start restricting their child's nutrition and suggest they consult with their child's paediatrician regarding any feeding questions.
Previous studies have shown that growth restriction before birth may cause lasting changes of genes in certain insulin-sensitive organs like the pancreas, liver and skeletal muscle. Before birth, these changes may help the malnourished foetus use all available nutrients. However, after birth these changes may contribute to health problems such as obesity and diabetes.
"This study shows that if we match the level of caloric consumption after birth to the same level that the growth-restricted baby received in the womb, it results in a lean body type. However, if there is a mismatch where the baby is growth-restricted at birth but exposed to plenty of calories after birth, then that leads to obesity," said Doctor Sherin Devaskar of Mattel Children's Hospital UCLA. "While many trials that include exercise and various drug therapies have tried to reverse the tendency of low birth weight babies becoming obese, we have shown that a dietary intervention during early life can have long lasting effects into childhood, adolescence and adult life."
About 10 per cent of babies in the United States are born small, defined as less than the 10th percentile by weight for a given gestation period, said Doctor Meena Garg. She added that some organisations define low birth weight as less than 2,500 grams or 5 pounds, 5 ounces at term.
Low birth weight can be caused by malnutrition due to a mother's homelessness or hunger or her desire not to gain too much weight during pregnancy. Additional causes include illness or infection, a reduction in placental blood, smoking or use of alcohol or drugs during pregnancy.
To conduct the study, researchers used rodent animal models and simulated a reduced calorie scenario during pregnancy. The results showed that low-birth weight offspring exposed to moderately tempered caloric intake during infancy and childhood resulted in lean and physically active adults related to high energy expenditure, as opposed to unrestricted intake of calories, which resulted in inactive and obese adults due to reduced energy expenditure. The authors concluded that early life dietary interventions have far reaching effects on the adult state.
MEDICA.de; Source: University of California Los Angeles