Antibiotics may improve growth in children at risk of undernourishment in low income and middle income countries, according to a recent study.

Researchers found that the youngest children in the most vulnerable populations benefit most from antibiotics. Significant improvements toward expected growth for their age and sex were also seen.

Malnutrition in early childhood, reflected in poor growth, is the cause of nearly half of all mortality worldwide in children less than five years old, according to a press release. The World Health Organization is currently recommending antibiotics for severely malnourished children, and those infected or exposed to HIV, to reduce mortality.

"Overall, we found that antibiotic treatment had a positive effect on both height and weight with increases of 0.04 cm/month for height and by 23.8 g/month for weight," Amee Manges, a professor in the School of Population and Public Health at the University of British Columbia, said in a statement. "After accounting for differences in the age of the study participants, effects on height were larger in the youngest children and effects on weight were larger in the trials that were conducted in Africa."

For the study, researchers examined literature for studies that treated children aged 1 month to 12 years with an antibiotic, and analyzed the results of 10 trials involving 4,316 children in seven low and middle income countries, researcher Ethan Gough said in a statement.

Researchers found that children were generally smaller in height and weight than adequately nourished children of the same age. This group of studies reflects the spectrum of stunting and wasting malnutrition seen in these countries.

"The overall gains in growth confirm the benefits of antibiotics in high-risk populations," Gough said. "However, more research is needed to better understand the underlying reasons for improved growth so that safer treatments can be developed."

The findings were recently published in the British Medical Journal.