The Sweet and Sour Connection: How Sugar Affects Mood and Gut Health

Sugar, the sweet temptress of our modern diet, has long been associated with pleasure and indulgence. Yet, emerging scientific research has revealed that the effects of sugar extend beyond the taste buds and waistline. This article delves into the intricate relationship between sugar consumption, mood regulation, and gut health.


Blood Sugar Swings and Mood

The most immediate impact of sugar consumption on mood can be attributed to its rapid influence on blood sugar levels. Scientific studies have shown that consuming sugary foods and beverages leads to a spike in blood sugar, followed by a subsequent crash. This fluctuation in blood sugar can result in irritability, fatigue, and mood swings.

Sugar’s Impact on Gut Health

Our gut, teeming with trillions of microorganisms collectively known as the gut microbiota, plays a pivotal role in both physical and mental health. Excessive sugar consumption can disrupt this delicate balance, a condition known as dysbiosis.

The gut microbiome plays a significant role in the production and regulation of neurotransmitters like serotonin and dopamine.

Serotonin, often referred to as the “feel-good” neurotransmitter, is primarily produced in the gut, specifically in the enterochromaffin cells (EC cells) of the intestines. These cells convert tryptophan, an essential amino acid found in the foods we eat, into serotonin with the help of enzymes.

Dopamine is another important neurotransmitter associated with mood, motivation, and reward. While the majority of dopamine is produced in the brain, there is evidence to suggest that the gut plays a role in its regulation. The gut-brain axis, a bidirectional communication network between the gut and the brain, is believed to impact dopamine production and regulation.


Tips for a Healthier Relationship with Sugar

Moderation: Rather than eliminating sugar, aim for moderation. Enjoy sweets occasionally but limit your daily intake.

Choose Natural Sugars: Opt for natural sources of sugar found in fruits, honey, or maple syrup, which come with additional nutrients and fiber.

Read Labels: Pay attention to food labels, as sugar can hide under various names like sucrose, fructose, and high fructose corn syrup.

Fiber-Rich Diet: Incorporate fiber-rich foods like whole grains, fruits, and vegetables into your diet to support gut health.

Postbiotic-rich foods: Include postbiotic-rich foods such as R’s KOSO, a postbiotic-rich beverage made with over 100 kinds of whole foods, to help maintain a healthy gut microbiota. R’s Koso provides postbiotics, prebiotics, and probiotics. It is fermented for over 1 year with the Japanese traditional method. If you are concerned about the sugar content in R's KOSO, try R's KOSO lower sugar. R's KOSO lower sugar contains  80% less sugar than R's KOSO original. You can also add fermented foods such as yogurt, kefir, natto, and sauerkraut.



The evidence strongly suggests that excessive sugar consumption can affect both mood and gut health. Understanding the relationship between sugar and these aspects of our well-being is crucial for making informed dietary choices. By moderating sugar intake, focusing on natural sources, and prioritizing a diet that supports gut health, we can help maintain a balanced mood and overall mental wellness.

Let’s get started!

Written by Eriko Shintani
Certified holistic nutritionist/Holistic nutrition advisor


1. Bear, T. L. K., Dalziel, J. E., Coad, J., Roy, N. C., Butts, C. A., & Gopal, P. K. (2020). The Role of the Gut Microbiota in Dietary Interventions for Depression and Anxiety. Advances in nutrition (Bethesda, Md.), 11(4), 890–907.

2. Appleton J. (2018). The Gut-Brain Axis: Influence of Microbiota on Mood and Mental Health. Integrative medicine (Encinitas, Calif.), 17(4), 28–32.

Older Post
Newer Post
Close (esc)


Use this popup to embed a mailing list sign up form. Alternatively use it as a simple call to action with a link to a product or a page.

Age verification

By clicking enter you are verifying that you are old enough to consume alcohol.


Main menu

Shopping Cart

Your cart is currently empty.
Shop now
Liquid error (layout/theme line 311): Could not find asset snippets/elevar-body-end.liquid HTMLResult Skip Results Iframe EDIT ON