Mood and food. What is the gut-brain connection?

14 Feb

Mood and food. What is the gut-brain connection?

When we have an intuitive thought we say “I’ve got a gut feeling that…. ”. When you look at the science behind that expression there are some really interesting facts about why our thoughts are connected to our gut but first let’s have a brief look at:

The brain

There are billions of nerve cells or neurons that carry messages around the brain to connect our brain cells. The neurons contain different types of neurotransmitters, such as serotonin, adrenaline, dopamine or acetylcholine. One of the most well-known being serotonin is also called the mood-balancing neurotransmitter. Did you know that serotonin is also produced in the gut where it has various functions? However, the research on whether the levels of gut serotonin affect levels of brain serotonin is still controversial.

Adrenaline is involved in motivation and like all neurotransmitters, is made from protein with certain vitamins and minerals needed to convert protein to adrenaline.

Dopamine is linked to concentration, alertness and feeling good. It is the neurotransmitter found in low levels in some cases of Parkinson’s disease and it is also involved in the pathway to produce adrenaline.

Acetylcholine is important for memory and mental alertness and is made from choline (see below for food sources of choline).

So, we can already start to see just how some of these neurotransmitters involved in mood and motivation are related to nutrients either from food that enters our gut or made in the gut.

The gut

This is your first defence line or the bridge between the outside world and your body. This is the hub where you convert all you eat and drink into nutrients to feed your cells and organs. The right nutritious food may support health while unhealthy foods may lead to health issues.

The gut is also where trillions of bacteria live which are vital to our health and wellbeing. Some of these have been considered as ‘beneficial’ and some as ‘unbeneficial’ bacteria. The ‘good’ ones have multiple roles such as converting fibre to make short-chain fatty acids that keep the gut healthy or breaking down food, converting food to nutrients and more.

The gut-brain connection

If there is an imbalance in gut health and bacteria then this may activate your defence system and release immune cells or inflammatory cells that can travel to the brain through a number of pathways: the nervous system, the immune system and through hormones. Inflammation in the brain has been associated with low mood and cognitive decline.

In contrast, when we become stressed from day to day living such as work or relationships, we activate the stress response, which has been shown in studies to reduce the balance of the gut microbiome. This can lead to the increase of unhelpful bacteria that can release inflammatory cells and the loop continues. 

Tips to support the gut-brain connection

Healthy protein, healthy fat and vegetables are not only full of nutrients, they also provide the energy or building blocks to support your gut and brain health (see What Powers Your Life).

Tips for the brain

  • Choline is found in food such as legumes, eggs, liver, broccoli and Brussel sprouts.
  • Tryptophan which converts to serotonin is found in chicken, turkey, fish, nuts, seeds, red meat, lentils, eggs and beans.
  • Avoid processed foods and deep-fried foods as these may increase inflammation in the gut or the brain.
  • Vitamin D may help to balance low mood and anxiety. It is mainly produced in the body from the sun but is also found in small amounts in sardines, mackerel, salmon, shitake mushrooms and egg yolk.
  • There are many studies to support omega 3 found in small oily fish and how it may support those with low mood.
  • Vitamins and minerals are important for the pathways creating your neurotransmitters and giving them the energy to function but supplements for supporting brain health should be taken with guidance from a qualified practitioner.

Tips for the gut

  • Natural probiotics such as yoghurt, kimchi, sauerkraut and kefir may help to support your beneficial bacteria. However, those with gut issues are advised to see a practitioner for additional recommendations as there are times when probiotics should not be taken.
  • Eating a wide variety of foods may provide nutrients to feed the beneficial bacteria.

Tips for both

  • Meditation and moderate exercise like walking, gentle cycling and swimming have been shown in studies to activate the “rest and digest” response which is the opposite to the stress response and may help to reduce inflammation, support digestion, and mental wellbeing.
  • Try meditation apps and mindful exercises like yoga and tai chi.

Remember, nothing in excess is helpful for your health and wellbeing. Moderate intake of foods and moderate lifestyle changes to support your mood is advisable.

Mental health is a much more complex topic than what has been discussed here and although diet and lifestyle changes may help to support brain health, it is important to seek medical guidance from your GP. Personalised nutrition looks at the root causes of health issues and looks at your health history to see how nutrition and lifestyle recommendations may help to support your physical health and mental wellbeing. For more information contact us here.

IFFM logo BioHealth
Functional Medicine logo BioHealth 2
Bant Member logo Biohealth
NLP logo BioHealth
CNHC logo BioHealth