New York, Sep 1 (IANS): As the obesity rate continues to skyrocket in the US, scientists across the country are combing the health records of 1.6 million kids to determine if childhood antibiotic use causes weight gain later in life.

"We know that childhood obesity is not only caused by genes, an unhealthy diet and too little activity, but likely the combination of several complex factors -- one of which may be the frequent use of antibiotics at a young age," said one of the researchers Ihuoma Eneli, Professor at Ohio State University, in the US.

"We have biological and statistical data that suggest there may be a connection, but we are looking for answers that can help us better understand this relationship and guide clinical practice in a way that will truly reduce a child's risk for becoming obese," she said in a university statement.

For the study, scientists will follow how many times children are prescribed antibiotics during the first two years of life, and then continue to track children to ages five and 10 to see how many of them are obese (i.e., heavier than 95 per cent of children of the same age and sex).

"The study is exciting because the electronic health record lets us drill down into specifics, quickly and at relatively low cost. For instance, it's possible that certain types of antibiotics are less likely to influence weight gain versus others," Eneli said.

"The study is also researching if the timing of when a baby first gets antibiotics or if the mother took antibiotics while pregnant has any impact on obesity," she added.

Eneli is part of a national research project -- the PCORnet Obesity Observational Study -- led by scientists at Harvard Pilgrim HealthCare.

Researchers expect their first round of data will be available early next year, and will lay the groundwork for spin-off studies that will look more closely at risk factors identified in this study.

"While we are still trying to answer the question about antibiotics and obesity -- there is one thing we know for sure: a diet high in refined sugars, processed grains and high fat coupled with a lack of exercise are huge risks for weight gain," Eneli said.

"By giving your child healthy food choices and encouraging physical activity, parents can help kids avoid obesity," she added.