food and mood

The surprising link between food and mood

Updated 14.01.24

Does gut health, food and mood really affect each other? In short, yes! What we eat nourishes not only our own cells but the 100 trillion microbes that live in our gut – our gut microbiome!

And we now know a lot more about why it’s important to nourish our gut microbiome, because it helps us digest and release nutrients from food, and so much more …

In fact, would you be surprised to learn that your gut microbiome is the secret link between food and mood?! And that gut health and mental health are firmly connected?

The connection between food and mood through the gut microbiome is a fascinating area of research. The gut microbiome contains trillions of microorganisms, including bacteria, viruses, fungi, and other microbes, and they’ve made your gut their home. In fact, we evolved alongside our gut bacteria, so there’s never been a time where we didn’t live in harmony with this army of little helpers!

For that reason, the gut microbiome plays a vital role in our health and well-being, including immunity and mood. And scientists now know there’s a strong link between gut health and mental health, so what we feed our gut bacteria matters for our mental health and well-being!

Science shows that if you improve gut health, it can boost your mood. It seems a far-fetched link, so how does the gut microbiome influence the connection between food and mood?

In a nutshell, our gut microbiome helps produce hormones and other molecules that have major effect on our brain – such as the happy hormone, serotonin. You may be surprised to learn that over 90% of serotonin is produced in the gut!

Here’s how the gut microbiome affects our mood:

Neurotransmitter production

The gut microbiome is involved in the production of neurotransmitters, which are chemical messengers that transmit signals in the brain. For example, certain bacteria in the gut can produce serotonin, a neurotransmitter that plays a key role in regulating mood. Imbalances in serotonin levels have been linked to mood disorders like depression.

Short-Chain Fatty Acids (SCFAs)

The gut microbiome breaks down dietary fibers and produce short-chain fatty acids (SCFAs) as byproducts. SCFAs have been shown to have neuroactive properties and can influence brain function. They may play a role in the regulation of mood and cognition.

Inflammation and immune system modulation

The gut microbiome influences the immune system and inflammation. Chronic inflammation is associated with various mood disorders, and an imbalance in the gut microbiome can contribute to increased inflammation. A healthy gut microbiome helps modulate the immune system, reducing inflammation and potentially benefiting mood.

Vagus nerve communication

The gut communicates with the brain through the vagus nerve. Signals from the gut can affect brain function and mood. Certain bacteria in the gut may influence the vagus nerve, impacting mood-related areas of the brain.

Nutrient metabolism

The gut microbiome plays a role in the metabolism of nutrients from the diet. Proper nutrient absorption and metabolism are essential for overall health, including brain function. Nutrient deficiencies have been linked to mood disorders, and a balanced gut microbiome contributes to better use of nutrients, to boost well-being.

Microbial diversity

A diverse and balanced gut microbiome is associated with better mental health. Negative changes in the composition of the gut microbiome, known as dysbiosis, have been linked to mood disorders. Consuming a variety of foods, particularly those rich in fiber and prebiotics, promotes microbial diversity.

Gut-brain axis

The gut-brain axis is a two-way communication system between the gut and the central nervous system, which includes the brain. Signals from the gut influence brain function, and vice versa. The gut microbiome is an important player in this communication. And science now shows that what we eat influences this gut-brain communication highway.

Nutritional psychiatry is the fancy term for finding out how foods affect our brain, and impact mental health conditions such as depression and anxiety.

Nutritional psychiatrist Prof Felice Jacka, has spent years examining the role of nutrition and brain health, and the results are fascinating – and sometimes downright frightening! For example, Prof Jacka found a clear link between the quality of what people’s diet and the size of their hippocampus, the area in the brain responsible for learning and memory. In fact, ultra-processed foods shrank the brain’s learning and memory center!

The good news is that your body and brain will respond quite quickly to positive dietary changes.

“… if we look at the literature from the dietary interventions for depression, we can see in as little as three weeks these really major changes”, says Prof Jacka.

What are the best gut-healthy good mood foods?

The good news is that if we take care of our gut health and the trillions of microbes in our gut, they will take care of us. Because a healthy gut microbiome is linked to better mood and mental health.

Boosting your wellbeing with gut healthy foods and meals can work wonders. For instance try to:

  • Eat fermented probiotic foods such as kefir, kimchi and kombucha
  • Think ‘variety’ and include different fish, nuts, fruits and veggies, and switch them up regularly
  • Limit ultra-processed and high-sugar foods
  • Follow a Mediterranean-style, high fiber diet
  • Move your body and try to get regular exercise

The link between gut health and mental health has been a catalyst for research into probiotics that have a positive effect on mood, mental health and well-being. As a reminder, probiotics are friendly bacteria that can do wonders for our gut health.

Turns out, a happy gut might just mean a happier mood!

We’ve just see how our gut microbiome can help produce neurotransmitters like serotonin, which plays a big role in regulating mood. But these gut bacteria need the right nutrients to support serotonin and other mood hormones. So, maintaining a balanced gut microbiome through probiotics could potentially have a positive impact on mental health.

Of course, it’s not a magical cure, but including probiotic-rich foods like yogurt, kefir, or supplements can be a tasty way to support your gut health. Plus, a holistic approach to mental well-being includes a mix of good nutrition, exercise, sleep and self-care. It’s all about finding that balance and giving your mind, gut and body the love they deserve.

While the link between the gut microbiome, food, and mood is a growing area of research, it’s important to note that individual responses can vary. Factors such as genetics, lifestyle, and overall health also play roles in how the gut microbiome influences mood. Consuming a balanced and varied diet, rich in fiber and nutrients, can contribute to a healthy gut microbiome and potentially support positive mental health.

So, here’s to a happy gut, a happy mind, and a happier you! 🌟


NOTE: This does not constitute medical advice. Seek advice from a healthcare professional as needed

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