Could germs be to blame for your toddler's temper tantrums?
The complex ecosystem of microbes living in the gastrointestinal tract is known to change considerably in the first two years of life, especially as solid foods are introduced into a child's diet. And according to a new study, this unstable "gut microbiome" and a toddler's temperament are linked.
"Although we predicted we would observe an association between temperament variables and measures of the gut microbial community, we didn’t know how strong those associations would be," Dr. Michael Bailey, associate professor of pediatrics at The Ohio State University and co-author of the study, told The Huffington Post in an email. "We do not yet know if these two factors are directly linked, and if so, in which direction the link occurs (i.e., gut to brain or brain to gut). It could be either, or it could be both."
Probing the poop. For the study, the researchers examined the different genetic types and varying amounts of bacteria found in stool samples from 41 boys and 36 girls between the ages of 18 and 27 months. The researchers also surveyed the children's mothers about the kids' temperament and eating patterns.
What did the researchers find? Children who were described as extroverted and upbeat tended to have more genetically diverse bacteria in their stool -- and that might mean there's a link between microbial diversity and a more positive temperament.
Not so fast. Does this finding suggest that parents can rein in an unruly toddler simply by changing his or her diet? Alas, not quite.
"We really are just beginning to realize that gut microbes can impact the brain and impact behavior," Bailey said in the email. "Until we know the extent to which this occurs, and the mechanisms by which this occurs, we really have no reliable way to predict how changes in diet, and thus changes to the microbiome, might impact toddler behavior."
The gut-brain connection. Previous studies showed that gut bacteria may be associated with various physical and mental health conditions, including anxiety, depression, obesity and diabetes.
The researchers plan to continue their research on the complex relationship between gut bacteria and behavior, as well as obesity. And other scientists agree that more research is needed.
"This study provides an initial glimpse of how the microbiota may be different between children that behave differently," Dr. Justin Sonnenburg, associate professor at Stanford University School of Medicine and author of the book "The Good Gut," who was not involved in the study, told The Huffington Post. "It will be important to see these very preliminary results performed in a relatively small cohort of children replicated in an independent study. Once replicated, it will be important to establish whether the differences in microbiota composition are causal for the behavioral differences, a result of behavior differences, or associated in some other way."
The study was published in the March 2015 edition of the journal Brain, Behavior, and Immunity.
In what other ways may microbes colonize and control our bodies? Check out the "Talk Nerdy To Me" episode below.