A bidirectional pathway called the gut-brain axis connects your stomach and brain. If you have depression or anxiety, the gut-brain axis makes it possible for these conditions to affect your gut and vice versa.

A bidirectional (two-way) communication path between your gut and brain causes one to affect the other’s functioning.

This relationship is known as the gut-brain axis. The gut-brain axis is what makes it possible for mental health conditions like depression and anxiety to cause issues in your gastrointestinal (GI) tract or gut.

Your gut can be highly sensitive to emotions. When you’re nervous, stressed, or anxious, the twisty feeling in your stomach isn’t just a fluke or a “gut feeling.”

That’s your brain, part of the central nervous system, signaling your gut’s enteric nervous system (ENS) — your “second brain.” Your ENS is specific to your gut. It comprises a wide network of nerves lining your gut.

This direct connection between your gut’s ENS and brain — the gut-brain axis — allows them to “talk” with each other.

When you’re in a difficult situation and get an upset stomach, your brain is signaling your gut to feel that way. And gut dysbiosis, or having an imbalanced gut, may also cause all kinds of mental health conditions.

The gut-brain axis may lead to mental health conditions, including depression and anxiety. The gut-brain axis can directly and significantly affect your digestive system, and your gut, in turn, can affect your mental status.

According to 2022 research, GI problems may increase your risk of depression by 7% and anxiety by nearly 9%.

Chronic stress, often related to depression and anxiety, releases stress-related neurotransmitters. These chemicals can trigger tumor development and certain cancers. A 2024 research has linked depression with gastric (stomach) cancer.

If you experience chronic stress, depression, or anxiety, speaking with a mental health counselor or therapist might help.

Other digestive issues associated with depression

Research from 2023 determined with data from 807,553 individuals links depression to an increased risk of:

Your gut creates approximately 95% of your body’s total serotonin, a “happy hormone.”

Conflicting research on whether reduced levels of serotonin have a role in the development of depression is available. Some research suggests there might be a connection, while other research has found no evidence of such a relationship.

Regardless, antidepressants that work by boosting serotonin levels (selective serotonin reuptake inhibitors) have shown they can effectively ease depression symptoms.

A 2019 study in mice found that low levels of serotonin in the:

This research suggests a treatment approach that addresses both gut problems and any underlying mental health conditions. But more human research is needed.

Better understanding the relationship between your gut and mental well-being is important for your overall well-being.

If you notice persistent stomach issues with symptoms of depression and/or anxiety, see a healthcare professional immediately. They can help you address your physical and mental health concerns.

A registered dietitian can also make some recommendations for changes in your diet.

Research suggests the gut-brain axis allows the gut and brain to communicate directly and bidirectionally.

But because of this direct relationship, a disturbance in your gut can lead to mental health conditions, and mental health conditions can disturb your gut.

Seek a healthcare professional right away if you have persistent stomach problems and anxiety and/or depression symptoms. They can recommend a treatment plan to improve your physical and mental well-being.