If you’ve watched the recent adaptation of Roald Dahls novel, Wonka, you might have been mesmerised by the little chocolate treats which seemed to bring consumers on a journey of emotions with each bite. From that “first love” feeling, to instant confidence, they had the townsmen absolutely hooked. Whilst this may be but a fictional movie, it has more parallels than you’d expect with how everyday snacks found in our grocery aisles impact our emotions.

Emerging research in the field of nutrition and psychology is shedding light on the profound impact our food choices have on our mood and overall mental well-being.

If you’ve ever found yourself reaching for that tub of ice cream or bag of crisps after a bad day (instead of that healthy grain bowl), you may be surprised to find out that they are designed exactly for that purpose. Natural selection and an innate survival mode essentially predisposes us to foods that are high in sugar and fats. Food scientists leverage this to create foods that are far higher in sugar, salt and fat than what one would find in nature. Why? To make them almost too hard to resist. Processed foods are formulated to produce a state of satiety, pleasure, and hedonia in consumers. It is no wonder that Britain's health boards have consistently been urging the government to implement a sugar and salt tax to break the countries addiction to junk food.

Sugar ‘High’ and ‘Crash’
‍Consumption of sugar triggers the rapid release of dopamine, the feel-good hormone which explains that temporary high you get after consuming a chocolate bar. The rapid spike in glucose in the blood stream can then lead to an overreaction and release of insulin, causing blood sugar levels to plummet below normal levels, often called the sugar ‘crash’. This leaves you feeling irritable, tired and moody - symptoms of hypoglycaemia.

Nutrients and Neurotransmitters
‍Our brains, the epicentre of our emotions and mental functions, rely heavily on the nutrients we consume. Certain nutrients play a pivotal role in the production and regulation of neurotransmitters, the chemical messengers that transmit signals in the brain. Serotonin, for instance, often referred to as the "feel-good" neurotransmitter, is influenced by the amino acid tryptophan found in foods like turkey, eggs, and nuts. Moreover, about 95% of serotonin is produced in the gut, which is lined with millions of nerve cells that when activated, pass on signals to the brain though a phone line-like network called the “gut-brain axis”. What you eat is basically the phone number your gut uses to call and direct your brain.

Gut Microbiome and its Metabolites
‍The function of our neurotransmitters are highly influenced by the types of bacteria in our gut. These ‘good’ bacteria not only protect the lining of your gut against toxins and ‘bad’ bacteria, they also help prevent inflammation, and can enhance absorption of nutrients from the food you eat. These bacteria and their metabolites can also help activate neural pathways between your brain and gut, through the “gut-brain axis”. In fact, there is growing evidence to suggest that gut dysbiosis (changes in the but bacteria composition) is associated with the onset and progression of depression.

The Social and Cultural associations of Food
‍Many of us will have learned from a young age that fruits, vegetables and whole grain items are what constitute a ‘healthy’ diet. Cakes, muffins, pizza and chips on the other hand, are easily categorized under the ‘unhealthy’ group. There is a specific guilt that develops after consuming a large amount these foods regardless of any biochemical reactions that they trigger in the body. Whether it is the disappointment of derailing ones diet goals, fear of gaining weight, or realisation that it was just a temporary solution to a bigger problem, our confidence and emotions are inherently tied to how we believe the world portrays a person who has their life together, and how we match up to that.

Food Nostalgia
‍Most of us will have a memory of food that brings you back to childhood. This is because food is a powerful elicitor of nostalgia. They are often more sensory than other memories as they involve all 5 senses. On the flip side, you may have felt a visceral churn in your stomach at the smell of vodka or tequila, or another specific food item you have had a bad experience with - that’s what Psychologist call conditioned taste aversion. You avoid that food because your mind has paired it with a past negative experience.

Perhaps Roald Dahl indeed before his time in predicting modern day science theories around food and its impact on how we feel when he wrote Charlie and The Chocolate Factory before his time. Whether it’s the chemicals and neurotransmitters in your brain, the memories unlocked, or the cultural perceptions interfering your emotions whilst eating, food clearly has a tremendous influence over our emotions and mood. There are ways to utilise this influence for the better, and learning to take control of these signals is key.

Perhaps Roald Dahl indeed before his time in predicting modern day science theories around food and its impact on how we feel when he wrote Charlie and The Chocolate Factory before his time. Whether it’s the chemicals and neurotransmitters in your brain, the memories unlocked, or the cultural perceptions interfering your emotions whilst eating, food clearly has a tremendous influence over our emotions and mood. There are ways to utilise this influence for the better, and learning to take control of these signals is key.

Written by Dr. Julia Craggs, January 2024

References:

https://diabetesjournals.org/diabetes/article/65/7/1797/16150/Is-Sugar-Addictive

The Gut-Brain Axis: Influence of Microbiota on Mood and Mental Health - PMC (nih.gov)

Gut microbiota and its metabolites in depression: from pathogenesis to treatment - eBioMedicine (thelancet.com)

https://www.thelancet.com/journals/ebiom/article/PIIS2352-3964(23)00092-0/fulltext#:~:text=Increasing

Check our Your Gut Knows podcast episodes related to this article: Mindful Eating & Food Meditation or Intuitive Eating.