Written by Ms Jill Barber for Doctify
Almost every single stock photo related to eating has people laughing uproariously at their meal. But is the food you’re merrily munching away on actually making you happy? We know that our diet can affect our physical appearance – sugar gives us spots, junk food makes us gain weight. Yet, when it comes to brain health, we tend to focus on things like how long we spend at the computer and whether or not we read enough.
Here to explain the (very real) connection between our gut and our brain is Nutritionist, Ms Jill Barber. As it turns out, that chocolate may not be making you as happy as you think.
Do you have the guts to be happy?
It may seem odd but how we digest food can affect our moods. Certain neurotransmitters are manufactured in the gut and affect our brain. So, it follows that it’s really important that our whole digestive system is in good order, so that these chemical reactions can occur.
Food is one of the last things people think about when they think about brain function. Neurotransmitters play a key role in cognitive function, behaviour and our well-being. Each cell used in the formation and function of the brain relies on specific micro and macro nutrients.
The connection between the gut and brain is known as the gut-brain axis (GBA). This is a two way communication between the central and the enteric nervous system, this is the link between the emotional and cognitive parts of the brain with intestinal functions.
One common example is when anxiety may lead to ‘butterflies in the tummy’ (Drossman, 2006).
It’s clear that good digestion is very important. The digestive tract is a long tube from the mouth to the anus. It exists within our bodies and yet its contents are excluded from our inner selves.
Its principal roles are:
- the digestion and absorption of foods
- the management of a co-dependent community of bacteria
- the development and maintenance of the mucosal immune system which is the largest section of immune tissues in the body
Listen to the brain in your gut
The gut contains the second largest network of nerves outside of our heads and has been called our second brain. A complex system of signals sends information between the gut and our brains. As a result, these connections help us eat food and aid our digestion but they do much more, they can also affect our mood. For example, when we have a stomach bug we can be nauseous, but surprisingly the key brain chemical serotonin is manufactured in the gut.
This chemical comes from our food except when we are fasting, when our gut bacteria manufacture it for us. So, changes in gut bacteria will change this key brain chemical and potentially our mood. Our community of gut bacteria is called our Microbiome. It is thought that tiny changes to this community can cause obesity in some people.
The human gut microbiome impacts the human brain health in numerous ways (3). The gut microbiota has the ability to produce a diverse range of compounds that play a major role in regulating the activity of distal organs and the liver is strategically positioned downstream of the gut. (1)
Recent advances in research have described the importance of gut microbiota in influencing these interactions. This interaction between microbiota and GBA appears to be bidirectional, namely through signalling from gut-microbiota to brain and from brain to gut-microbiota by means of neural, endocrine, immune, and humoral links. (2)
Gut microbiota links such diverse compounds as short chain fatty acids, bile acids, choline metabolites, indole derivatives, vitamins, polyamines, lipids, neurotransmitters and neuroactive compounds, and hypothalamic-pituitaryadrenal axis hormones have many biological functions. (1)
How can we feed this gut bacteria?
The foods that feed our bacteria are called Prebiotics. They include:
- chicory
- Jerusalem artichoke
- fennel
- onions
- garlic
- leeks
- peas
- beans
- lentils
- oats
- fruit, especially bananas
Foods that contain good bacteria tend to be fermented foods, such as:
- yoghurt
- kefir
- sauerkraut
- cottage cheese
- miso
- tempeh
- green tea promotes good bacteria (but it does contain caffeine)
It’s clear that the brain’s health and well-being can be significantly helped by the correct selection of foods and drink.