Mind-gut connection: stress, mental health and digestive wellness

Have you ever felt your stomach tight and like it's in a knot when feeling nervous? Or how you didn't feel like eating because you were upset or stressed? Researchers have long known that our thoughts and emotions affect our digestive system. However, in recent years, a growing body of evidence has emerged about how our digestive system and what we can eat can affect our mood and mental state. It could be why you get that 'gut feeling' influencing your thoughts.  

This bi-directional relationship between the mind and the gut is called the mind-gut connection.

As well as the brain in our head, according to Johns Hopkins Medicine,¹ we also have a brain in our digestive system, which scientists call the enteric nervous system (ENS). It consists of two thin layers of more than 100 million nerve cells lining the gastrointestinal tract from the oesophagus to the rectum. In fact, according to the Cleveland Clinic,² the gut has more nerve cells than anywhere else in the body outside of your brain.

As Cleveland Clinic describes, this "second brain" in the gut communicates back and forth with the brain via the vagus nerve as the main link between the enteric nervous system and the brain. When there is trouble or irritation in the gastrointestinal system, this "second" brain will send signals to the brain. John Hopkins¹ reports that researchers are finding evidence that these signals from the gut to the central nervous system (CNS) may trigger mood changes.

At the same time, the gastrointestinal tract is sensitive to emotion, as Harvard University³ reports, with many different feelings triggering symptoms in the gut.

In this way, a stomach upset can both be the result of and the cause of uncomfortable or negative emotions, such as stress. This means that if one is in poor health, the other will likely affect the other. For example, Jefferson Health⁴ reports an increase in gastrointestinal symptoms since before the pandemic, a time that brought stress to many.

In addition, feel-good hormones such as serotonin and dopamine, as Jefferson Health⁴ explains, are also produced in the gut by healthy gut bacteria and in the brain.

Stress is a common and prevalent factor in our lives and can often be found to cause digestive issues, especially when physical tests show everything is normal. 

According to The Anxiety and Depression Association of America,⁵ when feelings of anxiousness rise, the body releases hormones and chemicals that negatively interfere with digestion and the gut flora. 

Harvard³ explains how bowel symptoms, including pain, occur because psychology combines with physical factors to cause these, and stress can make the pain feel worse.

Managing stress with lifestyle approaches may be helpful. This can include scheduling and prioritising simple daily stress-relieving activities, such as walking yoga, mindfulness, journalling, and meditation. Seeking professional help from a counsellor or therapist and your social network may also be helpful. 

Given how much the gut can impact the health of the mind, keeping the gut and its microbiome healthy could be very beneficial. A diet full of healthy, whole foods to fuel healthy gut bacteria is recommended, and Cleveland Clinic² advises a diet with as much diversity as possible for good overall gut health. 

Along with lifestyle changes, some supplements may be of help.

There has been growing interest in the ancient remedies of adaptogens, as these plants or herbs have traditionally been used to help the body adapt to and cope with stress. 

According to Integris Health,⁶ Oklahoma's Largest Not-for-Profit Health Care System, to be classified as an adaptogen, it should help the body return to a state of homeostasis. Adaptogens are thought to do this by increasing or decreasing chemical reactions within the body as needed. 

For example, adaptogens can help reduce cortisol levels during stress while increasing them during other times of low cortisol. 

Adaptogens come in tea or powder form. Having them in tea is a great, calming way to consume them while helping reduce stress levels. 

A healthcare provider should be consulted for any adaptogens you may be considering. 

According to the Cleveland Clinic,⁷ studies have shown that taking adaptogens for a short period of time only is most effective, as the body may build a resistance to its effects. 

Ashwagandha

According to the Cleveland Clinic,⁸ Ashwagandha, an evergreen shrub found in parts of Africa and Asia, calms the brain's response to stress and regulates cortisol levels while aiding stress levels.

Rhodiola

Rhodiola is a plant that grows in cold regions and high altitudes in Europe and Asia as the National Center for Complementary and Integrative Health⁹ explains. It has long been used in Russia and Europe to increase endurance and relieve fatigue and is now used in a similar way to increase physical and mental stamina and strength and resist the effects of stress. 

Integris Health⁶ describes this plant as a stimulant used to reduce fatigue due to stress. According to the Cleveland Clinic,⁸ Studies show that Rhodiola helps improve performance during stressful situations. One 2022 review published in the Molecules Journal¹⁰ found that together with its long history of medicinal use, there was also extensive research to validate the effectiveness of the plant in protecting against stress.

Astragalus

Mount Sinai Hospital¹¹ describes the dried root of astragalus, a perennial plant native to China, Mongolia, and Korea, as being used in Traditional Chinese Medicine for thousands of years. It has many benefits, including defending the body against stress and acting as a restorative tonic.

Psychological

As John Hopkins University¹ explains, this increased understanding of the gut-mind connection has meant gastroenterologists may prescribe specific treatments because theythat may sometimes calm symptoms by acting on nerve cells in the gut. 

For example, psychological interventions like Cognitive Behavioural Therapy may also help to "improve communications" between the big brain and the brain in our gut. Another study from Harvard University³ found that psychologically based approaches improve digestive symptoms more than conventional medical treatment alone.

Dietary

Dietary supports such as increasing fibre, eating an organic, nutrient-rich diet as well as checking for food intolerances are often suggested. Supporting the bacteria in the gut, known as microbiota, is also important. This can be achieved by increasing probiotic yoghurt, kefir and fermented foods like sauerkraut or supplementing with probiotics may be indicated if gut bacteria is out of balance. 

A healthcare professional such as a naturopath is the best person to assist with determining if there is a mind-gut connection. They can help address digestive symptoms with diet and nutrients and support the nervous system with adaptogenic herbs if indicated so the whole body is being supported.