Have you ever noticed that your emotions are often accompanied by a gut response? You may feel butterflies when you’re nervous, nauseous when you’re anxious, and just plain hungry when you’re stressed or sad. This phenomenon not only has an explanation, but a name too! Today we’re talking about the gut-brain axis.
What is the gut-brain axis?
The gut and the brain are thought to be closely linked with each other through the bi-directional communication between the gastrointestinal tract and the central nervous system (the brain and spinal cord). This connection is known as the gut-brain axis. Most of this communication happens through the vagus nerve, which is part of the parasympathetic nervous system. This means that the functioning of this nerve is involuntary, and it is mostly responsible for digestion, heart movements and the immune system.
With a direct link to the brain through the vagus nerve, it is easy to understand why gut health is such an important factor, not only in overall health, but brain and mental health too. Recent research has shown a massive interest in this area, with studies working on demonstrating if diet could be a modifiable risk factor for certain mental illnesses. What current research has found so far is that diet plays a key role to mental wellness due to its impact on gut health.
How food affects your mood
The SMILES Trial (2012-2015) was the first study in the world to demonstrate that dietary changes could improve symptoms in people suffering from clinically-diagnosed depression. In this study, 32% of participants met criteria for remission from depression after 6 months on a modfied mediterranean diet.
In 2017, The HELFIMED Study was able to replicate and support evidence from The SMILES Trial. Participants with self-reported depression were prescribed omega-3 supplements and took part in cooking classes based on the Mediterranean diet. They reported significant reductions in symptoms of depression and found that these improvements were sustained up to six months after the intervention was completed.
While research in this area is still growing, results look promising so far! Around 45% (that’s almost half!) Australian adults will experience mental illness over their lifetime. Nutrition is a modifiable risk factor that shouldn’t be ignored. Because mental health exists on a continuum, good nutrition can have a positive impact even when you’re stressed, anxious, grieving or upset in your daily life, as well as when you’re experiencing chronic depression or other mental illness.
Diet changes for the health of your gut-brain axis
Oxidative stress may play a key role in the development of some mental illnesses. Colourful foods in the diet, in the form of a rainbow of fruit and veggies, are full of antioxidants, which are key for reducing oxidative stress.
FOCUS ON YOUR GUT HEALTH
Some neurotransmitters, such as serotonin, are produced in the gut. This means that gut health could be the key to how much serotonin is made and the rate of its uptake into the brain. This could have massive implications for the link between food and mood.
EAT MORE ANTI-INFLAMMATORY FOODS
Many mental illnesses are linked with inflammation. In fact, chronic low-grade inflammation is a risk factor for developing depression and, possibly, even age-related cognitive decline. The Mediterranean diet is associated with reduced inflammation, and may support brain and mental health in this way.
INCREASE YOUR INTAKE OF DIETARY FIBRE
Diets that are high in fibre (like the Mediterranean diet) have also been shown to support immune function and gut health. Fibre is used by gut bacteria to produce short-chain fatty acids, which play a key role in inflammation regulation. And since the immune system is influenced by the gut, improving the gut microbiome with more fibre can play a significant role as well.
BASICALLY, EAT A MEDITERRANEAN DIET
Current trials looking at the link between food and mood have found positive results in participants following a Mediterranean diet. Working one-on-one with an accredited dietitian is a useful strategy to familiarise yourself with this way of eating as well as to help you find nutritional support for your individual mental wellness.