A blog by Araminta Jonsson

The way that food can act as a medicine goes beyond simply eating your “5 a day”; there is a strong link between the food we eat and our mental health, and as cognitive functioning will be different from person to person it is worth understanding what we can alleviate with food, especially if you prefer not to take more traditional forms of medication, or if you are unable to. Umadevi Naidoo explains, ‘Clinical practice has shown that psychiatric patients experience increased morbidity and mortality associated with a range of medical illnesses. Furthermore, lifestyle, psychiatric medications, and inadequate health care all contribute to the poor physical health of people with mental illness.[1]’

Dr. Hyman states, 'What you put at the end of your fork is more powerful medicine than anything you will find at the bottom of a pill bottle.[2]' He argues that the Chinese have used food as pharmacology successfully for centuries, and encourages people to not only think of food as a way of staving hunger, but also as a way to improve our mood, health and wellbeing. Furthermore, in an article for The Lancet, Florian Daniel Zepf and colleagues identified that this concept of food as medicine is not a new theme, ‘in the 1970s, important research was done with a clear focus on nutritional aspects and related brain function and associated neurochemical properties, such as dietary availability of aminoacids like tryptophan that, in turn, serve as precursors for specific neurotransmitters in the brain such as serotonin.[3]’

Functional foods have been roughly defined as any food or ingredient that provides health benefits beyond the traditional nutrients they contain; for example fortified bread, juices and spreads, and garlic, honey, and turmeric. The difference between these two groups of examples are that the former are manufactured functional foods, and the second are natural. A concern exists amongst nutritionists that there is a risk of a growing dependence on manufactured functional foods for health benefits, as an alternative to a balanced diet and exercise.

It has been established that there is a link between microbiome and cognitive functioning. Umadevi Naidoo succinctly explains, ‘The human microbiome, which has co-evolved with humans, is a community of different bacteria that inhabit the body and is beneficial to humans.[4]’

A microbiome is defined as the microorganisms in a particular environment, for example a microbiome can protect us from germs, break down food to release energy and produces vitamins. Scientists, such as David Perlmutter have established that when there is a disruption in microbiome, it has an impact on the gut-brain axis which influences memory, mood and are ability to reason; what is more contemporarily known as being “hangry”. Most people can notice a change in mood when we are hungry, or when we have eaten significantly more take-away food than usual, but traumatic events can also have a significant impact on gut functioning[5], most commonly seen in Irritable Bowel Syndrome (IBS).

Scientists have recognised that microbiota interventions can be designed to help prevent and alleviate anxiety, depression, autism, chronic pain and Alzheimer’s disease. Furthermore, understanding how trauma disrupts the gut-brain axis has lead the way to design interventions to regulate the impact of trauma on gastrointestinal health.

Chris Kresser believes that if the brain is not functioning well, nothing else in the body will function well. He says that it is one of those really obvious things, that’s so obvious that we overlook it[6].

It is worth noting that while antidepressants can work very effectively for adults, it has proven to be potentially damaging for children. According to British psychopharmacologist Professor David Healy, 29 clinical trials of antidepressant use in young people found no benefits at all.[7] These trials revealed that instead of relieving symptoms of anxiety and depression, antidepressants caused children and young people to feel suicidal[8]. Furthermore, Florian Daniel Zepf and colleagues state ‘most neuropsychiatric disorders probably emerge during childhood or adolescence, and show a developmental trajectory.[9]’ This highlights the importance of understanding and nurturing the brain gut axis from an early age to help prevent poor cognitive functioning developing and accelerating in decline over time.

In his podcast, Kresser likens the body to a car; all the parts of the car need to work together to keep it moving, so when we talk about physiology we cannot ignore emotions, and vice-versa. Like Dr. Hayman, he applauds the Chinese ideology of the gut-brain axis, outlining the importance to think of psychology, physiology and emotions as not just connected, but the same; moving away from linear, causal thinking and adopting a more cyclical perspective.

Kresser seeks to explain and support the cyclical perspective; stating that once the brain is inflamed, what is known as “cytokines” are formed as a result of the initial inflammation will travel in the blood to disrupt the functioning in the gut, and so spreading the inflammation.

The symptoms of a disrupted brain-gut axis often involve a feeling of prolonged digestive discomfort that is not alleviated by diet change and most common are feeling unable to think clearly, paired with chronic fatigue. The more unknown symptoms are having cold hands and feet and having a fungus appear on toenails as a result of stifled blood flow.

To help prevent and manage disruptions in the brain or gut functions are to ensure the brain receives glucose, oxygen and stimulation. Stress management is key to ensure that these three things are reaching the brain. Cortisol, a stress hormone in the body, acts as a regulator for our blood sugar levels. So, if we maintain high levels of cortisol, it will prevent and dysregulate sugar levels that can lead to hypoglycaemia which begins to slow down and stop normal cognitive functioning; similar to that of “hanger”.

Kresser suggests incorporating fermented foods into the diet as a way to increase healthy gut functioning, as opposed to introducing an array of probiotic supplements. Dr Hayman also recommends incorporating different coloured foods, as they contain phytonutrients, which are plan chemicals that interact with biological functions to heal the body. He argues that there are over 25,000 chemicals that are beneficial to the body and encourages us to adopt a diverse diet.

As Kresser previously stated; it can seem so obvious that we might try everything else before doing the most simple. There exists wide and consistent research that points to the importance of diet on cognitive functions, so if other supplements and medicines are yet to help ease the symptoms; eat the rainbow!