Just about any yogurt commercial since time immemorial may remind you: Gut health is important. According to Harvard Health, healthy gut bacteria have been shown to play key functions in the body, playing a role in everything from processing nutrients in food to potentially helping to prevent and even treat certain diseases. Past research has linked stress and depression to a variety of digestive issues and illnesses, and scientists are interested in further uncovering the relationship between gut health and mental health.
A new study recently found that constipation and depression may both be linked to low levels of serotonin, a neurotransmitter that plays a role in regulating many functions, including appetite, sleep, and mood. The study in mice also suggests that experimental treatments that increase serotonin levels in the mice's guts and brains may help alleviate both conditions.
Past research supports the theory that some people with depression have lower serotonin levels, but this new study published in Gastroenterology links a lack of serotonin in the gut to constipation — considering how many With up to one-third of people with depression suffering from constipation, this relationship is noteworthy. Research shows that suffering from chronic constipation.
"The gut is often referred to as the body's 'second brain,'" Dr. Kara Gross-Margolis, the study's lead author, said in a statement. "It contains more neurons than the spinal cord and uses many of the same neurotransmitters as the brain. So it's not surprising that the two conditions may be caused by the same process."
The mice in the study all had a genetic mutation associated with severe depression in humans, which also impaired the mice's ability to produce serotonin in the brain and gut. They showed symptoms of depression, low serotonin levels in the gut, a deterioration of the gut lining, and a stagnation in the movement of substances through the mice's gastrointestinal tract - the equivalent of constipation in mice.
Researchers tested an experimental drug on mice to help increase intestinal serotonin levels to successfully treat constipation. But a link between serotonin levels in the brain and gut suggests the therapy might help treat both conditions, and the next step in the research is to test the drug in people with depression who are resistant to treatment.
Another similar study published recently found that transplanting gut bacteria from mice more susceptible to stress into more stress-tolerant mice made the latter more likely to engage in depression-like behaviors. "In mice that exhibited depressive-type behaviors in laboratory tests, we found that stress altered their gut microbiota — the group of bacteria in the gut," study author Dr. Seema Bhatnagar said in a statement. "When we When bacteria from those stress-prone mice were transplanted into non-stressed mice, the recipient animals showed similar behavior."
Mice susceptible to stress also had higher proportions of certain bacteria in their bodies compared to less stressed peers, a study that adds to a growing body of evidence detailing interactions between the brain and gut . These two studies lay the groundwork for future research focused on mental health treatments targeting areas beyond the brain. While more research is needed, these studies also provide a promising look at how stress and mental health disorders such as depression are related to and mediated by other factors such as gut health.
