Early antibiotic use may predispose children to weight gain and asthma.

The use of antibiotics in young children may alter the natural populations of gut microbes in a way that leaves them predisposed to weight gain and asthma in later childhood, according to new research.

The study of 236 children aged between two and seven, with a median age of five, backs earlier research on mice and children indicating the negative consequences of early antibiotic use. Antibiotics are the most commonly used drugs in childhood populations of western countries.

Researchers at the university of Helsinki said the use of antibiotics is associated with a long-lasting shift in microbiota – clusters of bacteria from different regions of the body – and metabolism. 

Humans and other animals are home to vast populations of microbes that live on the skin and in the gut. Humans carry around 100 trillion bacteria – meaning microbes outnumber human cells by 10 to one. But rather than causing us harm, studies suggest that a healthy “microbiome” is crucial for our wellbeing.

“Among the children who received macrolides (a class of antibiotic) in early life, we find a positive correlation between overall lifetime antibiotic use and body mass index (BMI), as well as an increased risk of asthma, suggesting that macrolide use may alter the microbiota in infants in a way that predisposes to antibiotic-associated weight gain and asthma in later childhood,” said the study published in Nature Communications.

Previous research on mice suggested that antibiotics are not directly to blame for weight gain later in life. Instead, the problem arose when antibiotics wiped out some types of gut bacteria but allowed hardier ones to thrive. This change in composition of the microbiome had a long-term impact on metabolism that persisted even when the population of gut microbes had returned to normal several weeks later.

Reddit on using a fecal transplant to fix this:

Since this is /r/science, it should be noted that in some cases, fecal transplant can result in at least a short term improvement in GI disorders. Fecal transplant is still pretty under researched. There are no long term studies that I know of. There is also little research on gut flora improvement, but it has had impact on symptomatic treatment of some GI disorders. The hypothesis is gut flora improvement. In fact, there is really interesting research on long term damage of transplants. An example would be new bacteria come in, dominate the biome killing off existing bacteria, but the new bacteria doesn't last, and when it dies off, the flora diversity could be worse off than before. This is one reason why so many good GI doctors are hesitant to try it out (and why so many desperate GI patients are trying it themselves).

1200+ Reddit comments:

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