Americans buy and consume more soft drinks than any other country in the world. People of all ages consume these products, including very small children. The consumption of soft drinks has already been linked to aggression, depression and suicidal thoughts in adolescent aged children, the same relationship had never been evaluated in children of a much younger age.  A new study published in the Journal of Pediatrics examined that relationship and found similar links.

A 2011 study published in the journal Injury Prevention found that teens who drank more than five cans of soda per week were more likely to have carried a weapon and acted violently toward peers, family and dates.

Shakira Suglia, ScD, Mailman School assistant professor of Epidemiology, and colleagues assessed around 3,000 children, 5 years of age, that were enrolled in the Fragile Families and Child Wellbeing Study, a mother and child study that follows pairs from 20 large cities. The mothers reported their child’s soft drink consumption and completed the Child Behavior Checklist, which is based on their child’s behavior during the previous two months. Researchers found that 43 percent of the children in the study consumed at least one serving of soft drinks per day and four percent consumed four or more.

Issues found to be associated with this consumption include aggression, withdrawal and attention problems. Even after adjusting for sociodemographic factors, maternal depression, intimate partner violence and paternal incarceration, soft drink consumption was associated with increased aggressive behavior. Children who drank four or more soft drinks per day were more than twice as likely to to destroy things that did not belong to them, get into fights and physically attack people. They also experience increased attention problems and withdrawal behavior compared to children that did not consume any soft drinks at all.

“We found that the child’s aggressive behavior score increased with every increase in soft drinks servings per day,” said Dr. Suglia. Although the study could not identify the exact reason of the association between soft drink consumption and problem behaviors, limiting or eliminating a child’s soft drink consumption could potentially reduce behavioral problems.

“Soft drinks are highly processed products containing carbonated water, high-fructose corn syrup, aspartame, sodium benzoate, phosphoric or citric acid, and often caffeine, any of which might affect behavior,” the authors write.

Caffeine is a likely factor, since other studies have connected the compound with changes in hormone levels that could alter the way still-developing brains perceive and evaluate risk. Caffeine can act on  many different brain systems, but there is still little information on its influence on young children. The FDA is currently investigating the safety of caffeine that is added to food products consumed by kids and adolescents, like drinks, chips and gum.