How Your Everyday Food Choices Are Influencing Your Mood

Everybody has good days and bad days — it’s a part of life. However, if you’re noticing that changes in your mood seem to be more drastic or frequent than usual, you may be wondering what factors are involved. 

One of the biggest everyday habits that may be contributing to ups and downs in your mood, including your experiences with anxiety and depression, is what you’re eating. Interestingly, a lot of it has to do with how certain foods influence your gut bacteria.

Keep in mind that everyone is unique and not all foods will affect everyone’s gut health the same way. The best way to understand how your diet is influencing your mood is to get specific about foods and mood symptoms, take notes on how you feel, and make adjustments from there.

The Microbiota-Gut-Brain Axis

Humans and our gut bacteria have developed strong lines of communication with and regulation of one another. As a result, the link between the communities of bacteria living in your digestive tract — called your gut microbiome — and your overall health is hard to argue against. 

There’s a growing body of scientific evidence that shows just how much your gut microbiome is influenced by your diet, and consequently how the rest of your health is impacted. This includes your mood, as well as diagnosable conditions like anxiety and depression.

For example, researchers have found that approximately 95% of the neurotransmitter serotonin in your body is found in your gut, with the other 5% made in your brain.¹ Serotonin is heavily involved in both brain and gastrointestinal health. Its main function is to regulate mood, including feelings of happiness. It’s also involved in your sleep cycle and the process of digestion. 

The link between gut bacteria and your brain is so strong that researchers have named it the “microbiota-gut-brain axis”. Evidence shows bidirectional communication between the two.² In other words, changes in your gut bacteria can impact what’s going on with your brain and mood, while changes in your mood can also affect your gut bacteria. 

Gut Bacteria and Mood

We each have over 100 trillion bacteria living in our digestive tract, which are especially populated throughout our intestines.³ And the diversity of our gut microbiome, or the types and amounts of bacteria that are present, is strongly associated with the mood-related behaviors we experience.

When we’re stressed or upset, it’s normal to crave certain foods that provide that temporary feeling of comfort we’re seeking. But these types of foods are often not at the top of the list when it comes to nutritional benefits, and can actually alter the balance of our gut microbiome by changing which types of bacteria thrive. 

On the other hand, those feelings of stress can influence our microbiome. Stress can reshape the bacterial balance through inflammation, stress hormones, and toxins that can alter eating habits and mood.⁴ Some bacteria may even continue to encourage our brains to crave less healthy, more palatable foods, and promote anxiety and depression. Some studies suggest they do this by altering brain reward pathways and taste receptors.⁵⁶ 

Furthermore, stress and depression may increase the permeability of our gut lining. This is sometimes referred to as having a “leaky gut”, which is the idea that gut bacteria can leak into circulation and trigger an inflammatory response. Over time, this can diminish gut bacteria diversity, promoting depression and reduced mood.

But just as there are foods that may work against a healthy gut microbiome, there are plenty of foods that have the opposite effect — improving bacterial diversity and mood. 

Let’s take a closer look at some of the foods and nutrients that help boost mood and which ones can have the opposite effect, depending on how they influence your microbiome. Remember that not all foods will affect everyone the same way, as we are all unique. 

Worst Foods for Your Mood

Some foods contribute nutrients associated with poorer gut health and mood outcomes, such as animal-derived protein, saturated fats, and added sugar.⁷ 

In other words, a typical Western diet pattern isn’t the best approach for healthy gut bacterial balance or promoting a positive mood. Eating these types of foods most of the time can promote chronic inflammation, which elevates the risk of having a poor mood. 

Some of the worst foods for your mood include:⁸,⁹,¹⁰ 

• Refined grains, such as white rice, pasta, bread, crackers, and snack foods

• Alcohol

• Baked sweets and pastries

• Added sugar

Best Foods for Your Mood

Gut- and mood-promoting foods provide nutrients like fiber, unsaturated fats, and plant-based protein. For example, researchers have found that adherence to a Mediterranean-style diet is associated with fewer depressive symptoms.¹¹

This doesn’t mean you have to adopt this exact pattern of eating to reap the benefits. But prioritizing healthier foods allows for more gut bacteria diversity and better mood outcomes. 

Some of the best foods for your mood include:¹²,¹³ 

• Whole grains, like whole-wheat bread and pasta, brown rice, quinoa, amaranth, millet, farro, and barley

• Vegetables, like broccoli, cauliflower, leafy greens, peppers, sweet potatoes, onions, garlic, squash, and mushrooms

• Flavonol and antioxidant-rich dark chocolate and cocoa 

• Fermented foods that contain probiotics and prebiotics, such as tempeh, miso, natto, kimchi, kombucha, and sauerkraut 

• Legumes, including beans, peas, and lentils

• Fruits, like berries, melon, bananas, apples, citrus, and grapes

Fueling Your Mood Through Your Stomach

There’s a strong link between what’s going on in your gut — in terms of the bacterial communities there — and what’s going on in your brain, especially when it comes to mood. Your gut and brain are in constant communication with one another, and their state of health is largely dependent on your diet. 

Eating foods characteristic of the Western diet, which are generally high in saturated fat, refined grains, and added sugar, tend to promote the survival of gut bacteria that negatively impact mood. Oppositely, eating foods that are rich in fiber, unsaturated fat, and plant-based protein can support a healthy gut-bacterial balance that promotes a positive mood and reduces stress.

It’s normal and okay to crave less-healthy comfort foods when you’re feeling down. It’s also normal to have a mixture of good days and bad days. What’s most important when considering how to support your mood through food is your overall diet, and doing your best to prioritize foods that offer a more uplifting outcome most of the time. 

Even the foods on the best and worst lists above may not apply to everyone the same way. You are unique and your body is dynamic, so it’s important not to generalize or guess when making connections between your diet and your mood. Instead, get specific about which foods are influencing changes in your mood, keep notes on types of food you eat and how you feel, and speak to your healthcare provider if you feel further support or testing is warranted. 

References:

1. Banskota S, Ghia JE, Khan WI. Biochimie. 2019;161:56-64. doi:10.1016/j.biochi.2018.06.008

2. Winter G, Hart RA, Charlesworth RPG, Sharpley CF. Rev Neurosci. 2018;29(6):629-643. doi:10.1515/revneuro-2017-0072

3. Liu L, Zhu G. Front Psychiatry. 2018;9:223. Published 2018 May 29. doi:10.3389/fpsyt.2018.00223

4. Madison A, Kiecolt-Glaser JK. Curr Opin Behav Sci. 2019;28:105-110. doi:10.1016/j.cobeha.2019.01.011

5. Bravo JA, Forsythe P, Chew MV, et al. Proc Natl Acad Sci U S A. 2011;108(38):16050-16055. doi:10.1073/pnas.1102999108

6. Cryan JF, Dinan TG. Nat Rev Neurosci. 2012;13(10):701-712. doi:10.1038/nrn3346

7. Wilson K, Situ C. J Clin Nutr Metab. 2017;1(2). pure.qub.ac.uk.

8. Gibson-Smith D, Bot M, Brouwer IA, Visser M, Giltay EJ, Penninx BWJH. Eur J Nutr. 2020;59(2):767-778. doi:10.1007/s00394-019-01943-4

9. Grases G, Colom MA, Sanchis P, Grases F. BMC Psychol. 2019;7(1):14. doi:10.1186/s40359-019-0292-1

10. Kose J, Cheung A, Fezeu LK, et al. Nutrients. 2021;13(5):1526. doi:10.3390/nu13051526

11. Gibson-Smith D, Bot M, Brouwer IA, Visser M, Giltay EJ, Penninx BWJH. Eur J Nutr. 2020;59(2):767-778. doi:10.1007/s00394-019-01943-4

12. Tuenter E, Foubert K, Pieters L. Planta Med. 2018;84(12-13):839-844. doi:10.1055/a-0588-5534

13. Liu RT, Walsh RFL, Sheehan AE. Neurosci Biobehav Rev. 2019;102:13-23. doi:10.1016/j.neubiorev.2019.03.023