April 8, 2019
Tummy troubles are pretty common in children. And even the most concerned parent may brush them aside, especially when they're not persistent. But a new Columbia University study might encourage parents to take a closer look at their child's gastrointestinal complaints—they could be a signal for future mental health issues.
Researchers studied the link between the gut and brain that's rarely been investigated in children. As part of their findings, which were published March 28 in the journal Development and Psychopathology, they explored the role of trauma and how it directly impacts both the gastrointestinal and mental well-being of individuals from a young age.
"Our study is among the first to link disruption of a child's gastrointestinal microbiome triggered by early-life adversity with brain activity in regions associated with emotional health," study lead author Bridget Callaghan, a post-doctoral research fellow in Columbia's psychology department, told Columbia News.
To reach the conclusion, the team also led by Nim Tottenham, a professor of psychology at Columbia University, analyzed the health of more than 330 youth between the ages of 3 and 18. They consisted of two groups: children adopted from orphanages or foster care and ones who were raised by a biological caregiver.
Researchers discovered those with a disruption early on in their caregiving demonstrated more stomach aches, constipation, vomiting, and nausea. The symptoms "were also associated with concurrent and future anxiety." This group also had different brain scans and gut microbiomes (the community of microorganisms in the gastrointestinal tract that impact digestion, the immune system, and other bodily processes) than children raised by a biological caregiver. The latter had higher levels of gut microbiome diversity, which is connected to the prefrontal cortex, the part of the brain that helps generate and regulate emotions.
While this study helps broaden our understanding of the gut-brain association in early childhood, the link between the two has long been reported. For example, there's evidence that psychological factors can aggravate Irritable Bowel Syndrome (IBS). And, according to Nasuh Malas, M.D., one of the most common signs of psychological distress is abdominal discomfort and other gastrointestinal issues.
"The gastrointestinal tract produces 95 percent of serotonin in our body, a neurotransmitter that impacts the presentation of depression and anxiety," says Dr. Malas, the director of pediatric consultation-liaison psychiatry at C.S. Mott Children's Hospital in Ann Arbor, Michigan. "We also know that youth with chronic gastrointestinal diseases, such as inflammatory bowel disease, celiac disease or others, have a much higher rate of depression, anxiety, [and are at] risk of increased stress and poorer quality of life."
As for psychological trauma, it "can change the release of certain hormones in the body, such as cortisol, that can impact the types of bacteria that grow in the gut," explains Marc Milstein, Ph.D., a Los Angeles-based biological chemist who specializes in the gut-brain connection. "Bacteria that grow in the gut in high concentrations of cortisol seem to be the types of bacteria that can then send signals of increased stress and anxiety to the brain." This can cause a "vicious cycle where high stress or trauma can lead to more feeling of stress and trauma through the gut brain connection."
Yet experts agree the Columbia University study is just the tip of the iceberg in our understanding of how youth experiences can influence lifelong health. But the information could work to shift physicians' perspectives. "This study has tremendous implications for how we treat physical illness down the road," says Maya Shetreat, M.D., integrative pediatric neurologist and founder of the Terrain Institute, a transformational healing program. "I think, as a result of this study, the medical community will have to do better in treating childhood trauma as part of the root cause of physical illness, rather than relying on pharmaceuticals to simply mask symptoms."