Washington: Baby rats which get normal levels of dietary fat right after birth, even though their mothers were fed high-fat diets, avoid obesity and related disorders as adults, according to new research.
Conversely, rat babies exposed to a normal-fat diet in the womb but nursed by rat mothers on high-fat diets become obese by the time they are weaned.
The experiments suggest that what mammalian babies - including humans - get to eat as newborns and young children may be more important to their metabolic future than exposure to unhealthy nutrition in the womb, Johns Hopkins scientists say, the journal "Diabetes" reports.
"Our research confirms that exposure to a high-fat diet right after birth has significant consequences for obesity," says Kellie L.K. Tamashiro, assistant professor of psychiatry and behavioural sciences at the Johns Hopkins University School of Medicine, who led the study.
"But it also suggests that by putting children on a healthy diet in infancy and early childhood, we can intervene and potentially prevent a future of obesity, diabetes and heart disease," adds Tamashiro, according to a Johns Hopkins statement.
Obesity has become a worldwide public health problem that often leads to many other disorders, such as cardiovascular disease, hypertension, type 2 diabetes, some cancers and arthritis.
Newborn baby rats exposed to a high-fat diet through the breast milk of rat mothers fed high amounts of fat were more likely to gain excessive weight, have impaired tolerance to glucose (a sign of pre-diabetes) and become insensitive to the hormone leptin, which regulates appetite and body weight in humans and rodents and can be disrupted in obese mammals.
Leptin, secreted by fat cells, signals how much fat is around and controls food intake; obese people often are insensitive to the signals, for reasons so far unclear.