Faster growing babies have higher IQ: study

Newborn babies who grow faster in the first four weeks are likely to have a higher IQ later in life, a new study has found.
Weight gain and increased head size in the first month of a baby's life is linked to a higher intelligence quotient (IQ) at early school age, the study led by University of Adelaide Public Health researchers found.
They analysed data from more than 13,800 children who were born full-term.
They found that babies who put on 40 per cent of their birthweight in the first four weeks had an IQ 1.5 points higher by the time they were six years of age, compared with babies who only put on 15 per cent of their birthweight.

Those with the biggest growth in head circumference also had the highest IQs.
"Head circumference is an indicator of brain volume, so a greater increase in head circumference in a newborn baby suggests more rapid brain growth," said the lead author of the study, Dr Lisa Smithers from the University of Adelaide's School of Population Health.

"Overall, newborn children who grew faster in the first four weeks had higher IQ scores later in life," she said.
"Those children who gained the most weight scored especially high on verbal IQ at age 6. This may be because the neural structures for verbal IQ develop earlier in life, which means the rapid weight gain during that neonatal period could be having a direct cognitive benefit for the child," she said.

Previous studies have shown the association between early postnatal diet and IQ, but this is the first study of its kind to focus on the IQ benefits of rapid weight gain in the first month of life for healthy newborn babies.
Smithers said the study further highlights the need for successful feeding of newborn babies.
"We know that many mothers have difficulty establishing breastfeeding in the first weeks of their baby's life," Smithers said.
"The findings of our study suggest that if infants are having feeding problems, there needs to be early intervention in the management of that feeding," she said.

The study was published in the journal Pediatrics.