How your gut affects your mental well-being

Scientists are learning more and more about the connection between the gut and the brain every day. Since these systems signal each other both ways, taking care of your gut may have an impact on your mental well-being.

The gut-brain axis

Scientists call the physical and biochemical connection between the gut and the brain the gut-brain axis. This two-way signalling system connects the gastrointestinal tract (GI tract) and the central nervous system (CNS).

Previously, communication was thought to be one-way, from brain to gut. In other words, although it was evident that certain mental states were related to certain functional GI conditions, it was unclear which way the connections ran. A new study suggests that mood changes may be caused mainly by imbalances in the gut that signal the brain.

“Our two brains ‘talk’ to each other, so therapies that help one may help the other,” says Jay Pasricha, M.D., director of the Johns Hopkins Center for Neurogastroenterology.

Below we look at four ways your gut health can support your mental health:

1. Exercise
Physical exercise not only releases feel-good endorphins and reduces stress, but studies also show it alters the composition of gut microbiota in a way that increases the production of short-chain fatty acids (SCFAs) that are beneficial for health.

Physical activity increases the number of beneficial microbial species in your gut and enriches microbial diversity. Even small increases in physical activity can have a significant impact on gut health.

2. Reduce stress
Your tummy is often the first place you feel stress in your body. Long-term stress can trigger GI issues such as constipation, digestive issues and diarrhoea, and chronic stress can lead to more serious issues such as irritable bowel syndrome (IBS).

Various studies indicate that yoga, mindfulness and meditation may be effective ways to reduce stress.

3. Get lots of sleep
A lack of sleep can lead to hormonal imbalances and an increase in the stress hormone, cortisol. There has been a link between increased stress and leaky gut syndrome, a condition in which food and toxins can pass through the intestines and enter the bloodstream.

An increasing number of scientists suggest that there may be a link between the digestive system and problems with sleep. While we know that a lack of sleep can affect our gut, could a balanced gut help with sleep?

“There is no question in my mind that gut health is linked to sleep health, although we do not have the studies to prove it yet," says Dr Michael Breus, a clinical psychologist and fellow of the American Academy of Sleep Medicine. "Scientists investigating the relationship between sleep and the microbiome are finding that the microbial ecosystem may affect sleep and sleep-related physiological functions in a number of different ways: shifting circadian rhythms, altering the body’s sleep-wake cycle, affecting hormones that regulate sleep and wakefulness."

4. Maintain a healthy diet
A good diet is one of the most effective ways to improve gut health. Be sure to consume a wide variety of fruits and vegetables in your diet.

You can support your gut health with a daily probiotic, and keep the beneficial bacteria in your gut happy by eating prebiotics, primarily fruits and vegetables that have fibre that feed them.

You can also benefit your gut health by limiting your intake of sugar, processed foods, and alcohol.

What we eat can also affect our mood. As one Harvard Health article explains, researchers have found that those who eat a traditional diet, such as the Mediterranean diet or the traditional Japanese diet, are at a lower risk of depression by about 25% to 35%. According to scientists, this difference is explained by the fact that these traditional diets tend to be high in vegetables, fruits, unprocessed grains, and fish and seafood, with only modest amounts of lean meats and dairy.

Want to learn more about the gut-brain axis? Explore our other articles and videos in our Learning Lab.