Gut Feelings: How Your Gut and Mind are Connected

Have you ever considered how your gut health may affect your mood? Research shows that digestive and mental health, including everyday mood, go hand-in-hand more than we may be aware. Now is an excellent time to better understand how to get more in tune with the connection between your gut and your mind.

The Gut-Brain Axis 

The connection between your gut and your brain is so strong that it is named the gut-brain axis. The gut and the brain work bi-directionally to communicate in real time about what’s happening in the body. 

Given that it’s the start of digestion, your mouth plays a significant role in this relationship through the oral microbiome. The health and activity of oral bacteria are directly connected to your brain and cognitive health. 

Both your digestive and nervous systems are full of neurons, which are cells that send signals telling your body what to do. One of the main ways the brain and gut work together is through the production of neurotransmitters and other chemical messengers that allow neurons to communicate with other neurons throughout the body. This includes effects on your mental health. 

If you’ve ever felt nausea when put in an anxiety-filled situation, felt “butterflies” when you’re nervous, or experienced feelings of hunger as soon as you start thinking about food, these are great examples of the instant link between the gut and the brain. Prolonged stress may contribute to changes in the digestive system over time.

Gut Health and Mental Health

Serotonin — a neurotransmitter heavily involved in emotions like happiness — is produced both in the brain and the gut, with nearly 95% made in the latter.¹ Bacteria in the gut also produce another neurotransmitter called GABA, which helps manage feelings like anxiety and fear.²

Furthermore, research suggests an association between the gut and mood, such as feelings of sadness.3 Gut dysbiosis, or an imbalance in the diversity of gut bacteria, has been linked to many health concerns. As a result, scientists believe that honing in on gut health is critical in supporting mental health.^4,5

How to Support Your Brain and Gut Health 

The gut-brain axis is innate, but properly fueling your brain requires properly fueling your gut. Below are some ways your diet can help support the health of both so they can continue working well together. 

Fermented Foods & Fibers

Most common fermented foods contain probiotics, the good bacteria that supplement your gut microbiome and populate the gut. Probiotics have been shown to alter brain activity, and some studies suggest that they may help improve mood.*^6,7 

Probiotics can be found in fermented foods such as tempeh, sauerkraut, yogurt with live active cultures, kefir, and certain types of cheese. 

Fiber is only found in plant foods, including fruits, vegetables, whole grains, legumes, nuts, and seeds. Prebiotics are present in fiber-rich foods, which are necessary for probiotics to thrive in the gut, making them an important component of gut health.  Most adults do not consume the recommended minimum amount of fiber. Research suggests that a high-fiber diet may alter neurotransmitter activity to improve mood.^10,11 

Incorporating a wide variety of these foods into your diet, which include probiotics and prebiotics, is essential for a healthy brain and gut.*

Omega-3 Fats

EPA and DHA are unsaturated omega-3 fats that may help support healthy gut bacteria as well as the nervous system.* Getting enough omega-3s may be beneficial for supporting mental health.*^8,9

Polyphenol Rich Foods

Polyphenols are naturally occurring compounds in fruits, vegetables, herbs, teas, and dark chocolate. They may increase healthy gut bacteria and support healthy cognition.*^12,13 

Some studies have found that a diet rich in polyphenols may help improve feelings of sadness and general mental health.*¹⁴

Tryptophan Rich Foods

Tryptophan is an amino acid that converts to serotonin. Consuming foods rich in tryptophan, such as cheese and eggs, may help support serotonin production. Some research has observed a positive impact of tryptophan on anxiousness and mood among healthy individuals.*¹⁵ 

Your gut and brain are always working together in intricate ways to support the health and function of your whole body. Eating a variety of nutrient-rich foods is a great practice to fuel both your body and mind.

References:

1. Kikuchi AM, Tanabe A, Iwahori Y. J Diet Suppl. 2021;18(3):316-333. doi:10.1080/19390211.2020.1746725

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

3. Mazzoli R, Pessione E. Front Microbiol. 2016;7:1934. Published 2016 Nov 30. doi:10.3389/fmicb.2016.01934

4. Järbrink-Sehgal E, Andreasson A. Curr Opin Neurobiol. 2020;62:102-114. doi:10.1016/j.conb.2020.01.016

5. Halverson T, Alagiakrishnan K. Ann Med. 2020;52(8):423-443. doi:10.1080/07853890.2020.1808239

6. Malan-Muller S, Valles-Colomer M, Raes J, Lowry CA, Seedat S, Hemmings SMJ. OMICS. 2018;22(2):90-107. doi:10.1089/omi.2017.0077

7. Dinan TG, Cryan JF. Brain-Gut-Microbiota Axis and Mental Health. Psychosom Med. 2017;79(8):920-926. doi:10.1097/PSY.0000000000000519

8. Mörkl S, Butler MI, Holl A, Cryan JF, Dinan TG. Curr Nutr Rep. 2020;9(3):171-182. doi:10.1007/s13668-020-00313-5

9. Menni C, Zierer J, Pallister T, et al. Sci Rep. 2017;7(1):11079. Published 2017 Sep 11. doi:10.1038/s41598-017-10382-2

10. Liao Y, Xie B, Zhang H, et al. Transl Psychiatry. 2019;9(1):190. Published 2019 Aug 5. doi:10.1038/s41398-019-0515-5

11. Quagliani D, Felt-Gunderson P. Am J Lifestyle Med. 2016;11(1):80-85. Published 2016 Jul 7. doi:10.1177/1559827615588079

12. Swann OG, Kilpatrick M, Breslin M, Oddy WH. Nutr Rev. 2020;78(5):394-411. doi:10.1093/nutrit/nuz072

13. Hayek N. Front Pharmacol. 2013;4:11. Published 2013 Feb 7. doi:10.3389/fphar.2013.00011

14. Brickman AM, Khan UA, Provenzano FA, et al. Nat Neurosci. 2014;17(12):1798-1803. doi:10.1038/nn.3850

15. Kontogianni MD, Vijayakumar A, Rooney C, et al. Nutrients. 2020;12(8):2445. Published 2020 Aug 14. doi:10.3390/nu12082445