Julia DeGrooth


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Majors: Biology and Psychology
Faculty Mentor: Dr. Victoria Templer, Psychology

Due to the prevalence of Major Depression worldwide, researchers have begun to search for alternative treatment methods other than antidepressants. Previous studies have shown that depression is affected by the gut microbiota, but the actual composition of the gut in Major Depressive Disorder (MDD) is not well understood. Here, I analyzed fecal samples of 100 participants with MDD and 100 healthy controls. One hundred people from the control and experiment groups were randomly and equally assigned to either a Mediterranean diet or a Western diet. According to previous research, fecal samples showed increased fecal diversity in MDD and Mediterranean diet group compared to the control groups (Western diet and healthy participants and Western diet and MDD). Increased levels of Bacteroidetes and Proteobacteria in the experimental group decreased the severity of depression according to the significant drop in PHQ-9 score. However, a high level of Lactobacillus and Firmicutes correlated to increased severity of MDD symptoms in the control group. The gut microbiome of the healthy control group did not improve their behavior or change their bacterial composition. These possible findings help understand predominant bacteria in the gut that are harmful and beneficial to MDD patients. Further studies need to investigate a causal relationship between the gut microbiome and major depression.


Providence College





Start Date

4-29-2021 12:00 AM






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