Antibiotics taken in childhood linked with higher risk of obesity

Taking antibiotics in infancy has been linked to a higher risk of obesity, a study suggests.

Researchers said the drugs may alter gut bacteria, making a child more susceptible to weight gain.

Antacids – drugs taken to curb excessive stomach acid – taken in the first two years of life may also have an effect, though much smaller, researchers from the US found.

The study, published in the journal Gut, found the effect was more pronounced among youngsters who used the drugs for a prolonged period.

Alterations in gut bacteria have been linked with obesity, and early exposure to medications can alter the bacteria.

The researchers set out to assess the use of antibiotics as well as histamine-2 receptor antagonist (H2RA) and proton pump inhibitor (PPI) antacid prescriptions during early childhood among those with a diagnosis of obesity.

They examined data on more than 333,000 infants whose medical records had been input into the US Military Health System database between 2006 and 2013.

Almost three-quarters (72.4 per cent) had been prescribed an antibiotic, while 39,488 (11.8 per cent) had been prescribed an H2RA and 11,089 (3.3 per cent) a PPI.

During the follow-up, 46,993 (14.1 per cent) children became obese, of whom 9,628 had not been prescribed any antibiotics or acid suppressants.

Boys, those born after a Caesarean section, and those whose parents were below officer rank were more likely to become obese.

Researchers also calculated that youngsters were 26 per cent more likely to be diagnosed with childhood obesity if they had been prescribed an antibiotic.

Because the study is observational it cannot establish cause but the authors wrote: “We found that outpatient prescriptions for antibiotics and acid-suppressing medications within the first two years of life are associated with the development of early childhood obesity.

“This association became stronger with prescriptions for more than one type of microbiota-altering medication.”