Search Here

Babies born at a lower birth weight are more likely to become obese adults, a new study suggests.

Researchers at the Baylor College of Medicine and the USDA/ARS Children's Nutrition Research Center (CNRC) at BCM and Texas Children's Hospital found that female mice who were growth restricted in the womb were born at a lower birth weight, but were less active and prone to obesity as adults.

"Given that human studies also show female-specific obesity following early growth restriction, it may be prudent to encourage parents of a low birth weight child to promote healthy physical activity - particularly if that child is a girl," Dr. Robert Waterland, associate professor of pediatrics - nutrition at BCM, and a member of the CNRC faculty said in a news release.

Researchers found that genetically normal female offspring of obese female mice were themselves prone to obesity and inactivity.  Researchers also found that the offspring of these overweight female mice were also growth restricted in the uterus.

Researchers said the latest findings are surprising because babies born to obese human women tend to be larger at birth, although there is a slightly elevated risk of low birth weight as well. Furthermore, when researchers looked at historical reports of people who had been born in famine conditions, they found that women, but not men, who had been growth restricted in early life were more likely to be obese.

Waterland said that once it was important to help babies born small "catch up and achieve normal weight for their age." However, he notes that recent studies suggest that this might actually harm the baby.

"Increasingly, these and other epidemiologic data show that it might not be a good thing. It might set you up for bad outcomes in the long term," he said.

While growth restricted female mice aren't prone to overeat, they become obese because they are less active. However, researchers noted that similar changes were not seen in male mice that were growth restricted in utero.

According to researchers, this makes sense evolutionarily speaking because in times of food scarcity, it might be more important for females to be developmentally 'programmed' to conserve their energy for future bearing of offspring.

"Millions of low birth weight babies are born every year, so this could be an important factor in the worldwide obesity epidemic," said Waterland.

The findings are published in the International Journal of Obesity.