Stress and anxiety can impact our gut—you only need to think of a time when you were nervous and it’s clear the impact it has on our gut. From slight ‘butterflies’ to feeling nauseas through to actually being sick or having loose bowels. On this blog I’ve frequently written about disordered eating (for example The Link Between Autism and Eating Disorders) but the gut/brain axis is something that impacts all of us.
The brain is a powerful organ; just thinking about food will mean that digestive enzymes are released into the gut ready for the impending food.
But what about the other way around? Can our gut health impact our mental health?
Many sufferers of irritable bowel syndrome (IBS) and other gut disorders can find it hard to hear that stress may be a factor. It can feel like their doctor is saying “it’s all in your head” or “just relax”. These platitudes are insulting and it’s certainly not what the doctor means! Changing lifestyle can have an profound impact on symptoms of IBS—not just a change in diet but looking after our mental health will reduce symptoms of IBS.
The British of Gastroenterology estimates that half of their patients have problems need support from a specialist in neurogastroenterologist. The problems encountered range from mild disturbance to intestinal failure.
“Stress hormones…impact bacterial balance. Symptoms may include heartburn and indigestion, abdominal cramps and pains, fullness, bloating, nausea, diarrhoea or constipation.”Dr Ayesha Akbar—consultant gastroenterologist at London Digestive Centre, Princess Grace Hospital
Understanding that the gut impacts the brain and the brain impacts the gut is the first step in being able to improve the health of both.
How are the gut and the brain linked?
500 million nerve cells line the gut. The vagus nerve connects the gut and the brain. This is the main component of the parasympathetic nervous system, which oversees many bodily functions including: mood, immune response, digestion and heart rate. Hormones, produced by the gut, send signals to the brain. The gut microbiome is what the most recent research is focused on—health gut flora leads to a healthy more resilient mind.
In times of stress, our colon becomes becomes more favourable to gut bacteria that produce symptoms of IBS. It has also now been found that gut bacteria interact with the brain by producing neurotransmitters. The bacteria species present can make anxiety and depression better or worse.
How can we take advantage of this knowledge?
We all know that certain food impact our mood, that’s why we have a favourite ‘comfort’ foods. The sugar ‘high’ and ‘crash’ is also something we all experience. We know that the food we eat impacts our brain but there are certain foods that influence the brain via the gut microbiome. Probiotics are the ‘good’ bacteria found in some foods. Prebiotics are a kind of fibre that feeds the ‘good’ bacteria.
“Foods that nourish our microbiome help serotonin production and reduce our stress response.”Dr Federica Amati—registered nutritionist, PhD in Clinical Medicine Research, Imperial College London
The following foods have been found to be most beneficial to include in our diet:
- Fruits and vegetables—try eating seasonally to become aware of new fruits and vegetables to try. Berries are particularly rich in polyphenols (prebiotic).
- Nuts and seeds
- Herbs and spices
- Olive Oil
- Probiotic foods include kefir, kombucha, sauerkraut, yoghurt, fennel, whole grains and dark leafy vegetables
- Prebiotic foods include bananas, garlic, asparagus, artichokes, oats and apples
- Sources of B vitamins include dairy food, eggs, meat, legumes and fortified foods such as breakfast cereal
B vitamins are essential for effective communication between nerve cells. When anxious, we use of B vitamins more quickly. At times of increased stress it could be helpful to take a good quality multivitamin.
It’s also important to avoid refined sugar which can decrease the number of gut bacteria. Instead use honey, maple syrup, molasses, stevia, dates and applesauce or other fruit purées.
If you feel you need help to balance your gut-brain axis, it’s important to consult your primary care physician or general practitioner.