Oct. 23, 2023 – Following a Mediterranean diet may help people exposed to trauma limit how severe their posttraumatic stress disorder symptoms are, a new study suggests.
The research builds upon a growing body of evidence that mental health and emotions are affected by microorganisms in what scientists call the gut-brain axis, which is a two-way communication pathway between the brain and the intestines.
The findings were published this month in the journal Nature Mental Health. For the study, researchers compared diet data, stool samples, and reported PTSD symptoms among 191 women. The women, who were all registered nurses, contributed their health information to a research databank in 2008 and 2013. This latest analysis, done by researchers at Harvard T.H Chan School of Public Health, found that women who did not follow a Mediterranean diet had more severe PTSD symptoms.
PTSD affects 4% of people worldwide, the authors noted, and arises sometimes after people experience or witness traumatic or terrifying events such as accidents, physical or sexual assaults, war-related events, or natural disasters. Symptoms of PTSD include re-experiencing the trauma, avoiding recollections, numbing emotions, as well as sleep problems, crankiness, hypervigilance, and an exaggerated startle response. The women in this latest study were screened for exposure to trauma using the National Center for PTSD’s Brief Trauma Questionnaire.
When the researchers analyzed the stool samples, they noted that people’s gut microbiome shared traits with those of others who had similar body mass indices, or BMIs, and also among people who had depression or took antidepressant medications. (Your BMI is a measure of body fat, based on your height and weight.)
Analysis of PTSD symptoms based on people’s dietary patterns showed that those who followed a Mediterranean diet had fewer PTSD symptoms, and eating red and processed meats was linked to more symptoms. Overall, eating plant-based foods was linked to fewer symptoms.
The researchers looked at specific microorganisms in the people’s gut microbiome and found that those who followed a Mediterranean diet had higher levels of Eubacterium eligens, bacteria that are linked to vegetables, fruits, and fish that are major parts of the Mediterranean diet. Meanwhile, Eubacterium eligens is less likely to be common among people eat red or processed meat.
“It’s exciting that our results imply that the Mediterranean diet may provide potential relief to individuals experiencing PTSD symptoms,” author Yang-Yu Liu, PhD, a statistical physicist in the Department of Medicine at Brigham and Women’s Hospital, said in a statement. “We are eager to learn more about the relationship between PTSD, diet, and the gut microbiome. In a future study, we will attempt to validate the efficacy of probiotics as a method to prevent PTSD.”