Childhood Obesity Risk Linked to Antibiotics Before Age Two: Study

New Delhi: A new study suggests that administering antibiotics during the first two years of a child’s life could increase the risk of developing a higher body mass index (BMI). Researchers from the University of Oulu in Finland found that children who were exposed to antibiotics during this critical period had a 9% higher chance of being overweight and a 20% higher chance of becoming obese compared to children who were not exposed to antibiotics during the same time.

Interestingly, the study showed no connection between BMI and antibiotic use before pregnancy, during pregnancy, or at birth. “Antibiotic exposure during the first two years of life has a stronger link to childhood weight gain than exposure during pregnancy or other early stages,” said Sofia Ainonen, a medical doctor at the University of Oulu. She stressed that healthcare providers must be cautious about prescribing antibiotics to young toddlers, especially for conditions like upper respiratory infections, where antibiotics may not be necessary.

The findings are especially significant as childhood obesity continues to be a growing global issue. In 2022, over 159 million school-aged children worldwide were diagnosed with obesity. Childhood obesity not only affects physical health but can also have a serious impact on mental well-being. It is linked to lower academic performance, reduced quality of life, and social issues like bullying and discrimination. Additionally, childhood obesity is associated with a higher risk of developing non-communicable diseases later in life, such as type 2 diabetes, cardiovascular diseases, and certain types of cancer.

The study followed 33,095 children born vaginally in Finland, assessing the impact of antibiotic exposure before, during, and after pregnancy on BMI at ages two and twelve. Previous research has shown that antibiotics can disrupt gut microbiota, which is key in regulating metabolism and weight. The findings were presented at the Pediatric Academic Societies (PAS) 2025 Meeting in Honolulu, Hawaii.