By Staff Writer (media@latinospost.com) | First Posted: Oct 22, 2015 08:50 AM EDT

A new study showed that children who took antibiotics are more likely to gain weight later in life. Exposure to antibiotics can actually affect a person’s body mass index or BMI, according to researchers.

TIME reported that the largest and longest study yet monitored how antibiotics can change people’s tendency to gain and retain weight over time. The findings were published in the International Journal of Obesity.

Brian Schwartz, lead author and professor of environmental health sciences at the Johns Hopkins Bloomberg School of Public Health, studied the electronic health records of 142,824 children from three to 18 years old. The researchers categorized antibiotic prescriptions based on their effects on BMI. They grouped the effects as follows: temporary, reversible, weight gain associated with the drugs was lost within one year, long lasting effects and weight not lost.

The study showed that taking antibiotics in the previous year before the children’s BMI was measured rendered weight gain results. The weight, however, was lost right after the medication was stopped. As for the cumulative effects of the drugs, the scientists observed that those who took antibiotics were more likely to gain and retain weight, as well as continue gaining weight when they reach 18 years old, compared to children who did not take any antibiotics.

Schwartz stated that the more antibiotics that a person receives, the stronger the effect will be. The effect also appears to grow as the person ages. Overall, antibiotic consumption caused a weight gain of 1.6 to 3.3 pounds during childhood, based on the same TIME report.

Schwartz stated that the long lasting weight gain may be triggered by the effect of the drugs on the microbiome or the bacteria that reside in the gut. The medications may alter the constitution of the good bacteria, responsible for digesting food and boosting the immune system, and cause changes like weight gain. Antibiotics can eliminate microbiomes and other less beneficial bugs may substitute, resulting to a change in weight.

Schwartz said that one antibiotic can wipe out all of the microbiome in the intestine. The microbiome can recover if antibiotics are taken less frequently. Taking more drugs can have permanent effects on the microbiome, which also explain long lasting weight gain.

The results should caution people to take antibiotics in moderation and only when truly necessary. Children can be at risk for becoming overweight or obese, even with proper diet and exercise, by consuming too many antibiotics, the Wall Street Journal wrote.