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The Gut-Brain Connection – How Functional Medicine Targets Digestive Health for Mental Well-being

Gut Health

Something really interesting about the body is that it can experience a stress response from physiological causes such as inflammation in the gut. It treats physiological stress and mental stress caused by trauma or other external factors the same, producing the same reaction through stress hormones.

In our Functional Medicine clinic, we see many of our patients significantly reduce symptoms of stress, anxiety, depression and poor mental well-being by changing their diet. The stress response subsides by using food as medicine to address physiological stress in the gut and immune system. This is why digestive health makes such a difference to mental well-being.

Is your gut supporting your well-being?

You may not realise it but your gut and your brain are constantly sending messages to each other. It’s very much a two-way conversation. That’s why when you’re nervous about something, you have the sensation of butterflies in your stomach. Anxiety can produce an effect so profound on the gut that people feel incredibly nauseous and even vomit. 

The connection flows the other way as well. Gut issues with completely physiological causes can affect mental well-being because of the communication between the gut and the brain. So a physiological problem can turn into a mental problem due to the gut signalling to the brain that something is wrong.

For example, cortisol is the primary stress hormone that, at high levels, causes symptoms such as hyperventilation, breathlessness, anxiety, inability to sleep and tremors. We know that inflammation in the body also increases cortisol, triggering its side effects. We also know that reducing inflammation by restricting foods that trigger inflammation and increasing foods with anti-inflammatory properties reduces cortisol levels and stress-producing effects.

For fully healthy digestion and healthy functioning, we need to consider what’s going on in the gut and the mind, addressing both potential causes of poor mental wellbeing and utilising both methods to improve mental wellbeing. 

Are your levels balanced?

While we are looking to balance all vital levels in the body, we know certain levels are connected to well-being, directly or by reducing inflammation. For example, stabilising blood sugar levels can make a real difference to well-being. Spikes and drops in blood sugar give people highs and lows in energy that aren’t productive. By replacing processed and high-sugar foods with high-fat, high-protein, homemade foods, your blood sugar and, as a result, your energy levels will be much more stable. 

Make sure you are getting your omega 3 through low-mercury fish or high-quality supplements to support brain health. 

Amino acids are also important, particularly taurine, a calming neurotransmitter found in meat and fish. Fat-soluble vitamins, B vitamins, and fibre also reduce inflammation and heal the gut. 

The key 3 vitamins for mental well-being

For patients who report symptoms linked to poor mental well-being, we always check their levels of vitamin B12 and vitamin B9. Together, B12 and B9 (AKA folate or folic acid) enable a process called methylation for the building and repair of all systems in the body. We know that a lack of methylation is linked to physical symptoms such as autoimmunity and digestive issues as well as reduced mental well-being, including anxiety, depression and insomnia. 

Unfortunately, B12 is particularly complicated to absorb, so if there is damage to the stomach, a lack of acid due to stress, or you’re not consuming enough of it, you’ll become deficient. It really is tricky because a healthy person can have up to 7 years of B12 stored in the body, so it can take a long time to see signs of the deficiency. Drugs such as antacids and diabetes medications can cause B12 absorption issues, too. B12 can only be found in animal products – meat, fish, dairy and eggs – so it does need to be supplemented on a wholly plant-based diet. B9 is best found in vegetables, although it can be found in some meats like liver. 

Another vitamin to keep an eye on is vitamin D. The best way to absorb it is from the sunlight hitting our skin. Depending on where you live in the world, that’s easier said than done. In the UK, we can only get vitamin D from the sun between March and October. You can get some types of vitamin D from produce, such as vitamin D2 from eggs and fish. However, vitamin D3, which is really important to our immune system and well-being, needs to be supplemented or come from sun exposure. So, everyone in the UK should be taking a vitamin D supplement.

Is well-being all about the body?

While treatments like a round of B12 vitamin injections to quickly increase levels and reduce anxiety can be a comprehensive solution for some patients, we do understand that some causes of poor mental well-being are internal (due to the body not having the building blocks it needs to function optimally). Others are external (as stress is a normal reaction to high-pressure situations). Therefore, alongside testing a patient’s levels and creating a food plan to rebalance critical levels of vitamins, hormones, minerals and other factors, consultations with patients showing signs of poor mental well-being will include discussions of their life as a whole. 

We are happy to suggest additional stress management treatments such as meditation, breathing exercises and psychotherapy. If a patient has experienced trauma, it’s quite common for them to have high cortisol levels, which we can help them manage until they arex` ready to go to therapy to deal with the root cause of their stress reaction. 

Functional Medicine is all about highly specific personalisation, so how we support our patients struggling with poor mental health varies. It often includes a combination of supporting their gut health for optimal body function, addressing key nutrient levels associated with symptoms of poor functioning (such as rebuilding vitamin B12 levels), and signposting to external mental well-being support. This ensures all causes of diminished well-being are factored into their long-term healthcare plan. 

Our Functional Medicine Doctors are ready to put together your personalised long-term healthcare plan via our clinic or our Functional Foundation Programme.

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