Health professionals have long known about the benefits of breastfeeding for babies, but new research reveals that the food babies eat in their first days of life may have a long-term impact on their health.

Presented May 2 in the US at the Pediatric Academic Societies, the results of the study conducted at Claude Bernard University in Lyon, France showed that babies who were breastfed for the first four months of life had lower blood pressure at the age of three compared to high protein formula-fed babies.

Breastfed babies also had slightly larger heads than those who ate low-protein formula. In addition, infants who were breastfed for the first 15 days of life had lower levels of insulin in their blood compared to formula-fed babies, although this difference disappeared by the time the babies reached nine months old.

Both groups fell within the normal range for blood pressure and head size, but the study raises questions as to what long-term impact, if any, this may have on a baby's life, and whether the difference disappears in time.

"It appears that formula feeding induces differences in some hormonal profiles as well as in patterns of growth compared with breastfeeding," study researcher Dr. Guy Putet said in a statement. "The long-term consequences of such changes are not well understood in humans and may play a role in later health."

The researchers suggest that the amount of protein in the babies' diet might be a possible factor in these differences. Breastfeeding is best, Putet said, but as a second option, feed your baby with a formula that produces a growth and hormone pattern similar to that of breastfed babies. Talk to your pediatrician about the best options for your baby.

Prior studies have shown that breastfeeding offers a myriad of benefits for babies, including reduced risk of obesity and diabetes, lower rates of respiratory problems, less incidences of eczema, fewer ear infections, stomach infections, and chest infections, and a possibly reduced risk of sudden infant death syndrome.

The World Health Organization and UNICEF recommend exclusive breastfeeding for the first six months of life.

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