How Gut Dysbiosis Drives Sugar Cravings
If you constantly crave sweets, your gut microbiome might be to blame. Research shows that gut bacteria can influence cravings, appetite, and even mood, sometimes in ways that serve them more than us. Certain microbes thrive on sugar and may increase cravings to secure their energy source, while others produce compounds that impact mood, making us feel worse until we eat foods that support their growth.
Are Food Cravings Really a Sign of Nutrient Deficiency?
It’s tempting to think that food cravings signal a lack of essential nutrients. After all, iron-deficient children sometimes eat dirt, which supports this idea. However, research shows that fasting tends to reduce cravings rather than increase them, contradicting the idea that cravings are simply the body's response to missing nutrients (Alcock, et al.).
The Link Between Gut Health and Cravings
The connection between gut health and food cravings is surprisingly strong. Studies reveal that people who crave chocolate have different gut microbiome byproducts in their urine compared to those who don’t—even when both groups eat the same diet (Rezzi, et al.). This suggests that gut bacteria may influence not just cravings but also how we metabolize certain foods.
Can Gut Bacteria Affect Your Mood?
Beyond food cravings, gut bacteria also play a role in mental health. A double-blind, placebo-controlled trial found that taking a probiotic drink with Lactobacillus casei significantly improved mood in participants who initially reported feeling the lowest (Benton, et al.). This highlights how gut dysbiosis may contribute to emotional eating and sugar cravings.
How Gut Dysbiosis Hijacks Your Cravings
Scientists have identified several ways in which gut microbes influence eating behavior, and for those with chronic illness, these effects may be even more pronounced. Research suggests that lower gut microbiome diversity—a common issue in ME/CFS, fibromyalgia, and long-haul COVID—can impact satiety signals and eating behavior. When beneficial bacteria are reduced or imbalanced, it can lead to stronger cravings, poorer blood sugar regulation, and disruptions in hunger hormones like ghrelin and leptin.
How Gut Bacteria Control Hunger Hormones
Hunger and cravings don’t just come from habit or willpower—they’re heavily influenced by gut-derived hormones.
Ghrelin ("the hunger hormone") increases appetite and may amplify cravings through dopamine pathways.
GLP-1 and PYY signal fullness and regulate eating behavior.
Short-chain fatty acids (SCFAs), produced by beneficial bacteria, stimulate GLP-1 and PYY while lowering ghrelin.
A healthy gut microbiome plays a direct role in this balance. Short-chain fatty acids (SCFAs), which are byproducts of fiber fermentation by beneficial bacteria, stimulate the release of GLP-1 and PYY while also reducing ghrelin production. When microbiome diversity is low, SCFA production can drop, potentially leading to weaker satiety signals, increased hunger, and a stronger drive to seek out high-calorie, sugary foods (Gupta, et al.). Low SCFA production has been demonstrated in postviral conditions and fibromyalgia.
The Gut Microbiome and the Brain’s Reward System
Cravings aren’t just about hunger—they’re also about dopamine and the brain’s reward system. Some gut bacteria can directly influence this system by producing dopamine, effectively hijacking the brain’s pleasure pathways to encourage certain food choices.
Several gut microbes, including Escherichia coli, Bacillus cereus, B. mycoides, B. subtilis, Proteus vulgaris, Serratia marcescens, and Staphylococcus aureus, have been found to produce dopamine, potentially reinforcing cravings (Tsavkelova, et al.).
How Gut Dysbiosis Can Change Taste Perception
The intestines do more than digest food—they also contain taste receptors, much like those found on the tongue. These receptors detect sugars, amino acids, and other nutrients, helping regulate digestion and appetite. Emerging research suggests that certain gut bacteria may manipulate these receptors to reinforce cravings for specific foods that help them grow.
How to Reduce Sugar Cravings by Fixing Gut Dysbiosis
If your gut microbiome is fueling food cravings, especially sugar, rebalancing it is key. Here’s how:
Increase Fiber and Prebiotics – Support beneficial bacteria with resistant starches, flaxseeds, and low-glycemic carbohydrates. Add resistant starch to your diet to increase SCFAs.
Reduce Added Sugars Gradually – Cutting sugar too quickly can trigger intense cravings; stabilizing meals with protein and healthy fats helps.
Support Beneficial Bacteria – Eat probiotic-rich foods (fermented vegetables, unsweetened yogurt) or take high-quality probiotic supplements.
Address Yeast Overgrowth – If Candida is a factor, reduce simple carbs and consider natural antifungals like oregano oil or Saccharomyces boulardii. Read more about a Candida protocol.
Who’s Really in Control—You or Your Gut Microbiome?
If gut bacteria can manipulate neurotransmitters, hunger hormones, and even taste receptors, then how much of what we eat is actually our choice?
It’s an unsettling thought—are we making decisions based on personal willpower, or are trillions of bacteria influencing our cravings from the inside? While this doesn’t mean free will is an illusion, it does highlight the deep biological influence of the gut microbiome on what we eat, how we feel, and even what we think we want.
Gut dysbiosis doesn’t just impact digestion—it can directly influence cravings and eating behaviors in ways that challenge our sense of autonomy. If you’re experiencing persistent sugar cravings, addressing your gut health may be a crucial step.
Lack of microbiome diversity is common in ME/CFS, fibromyalgia, and long-haul COVID, and restoring balance can help regulate blood sugar, appetite hormones, and neurotransmitters—reducing the biological drive for sugar and supporting overall well-being.
And maybe, just maybe, it puts you back in the driver’s seat instead of letting your gut microbes call the shots.
References
Alcock J, Maley CC, Aktipis CA. Is eating behavior manipulated by the gastrointestinal microbiota? Evolutionary pressures and potential mechanisms. Bioessays. 2014;36(10):940-949. doi:10.1002/bies.201400071
Rezzi S, Ramadan Z, Martin FP, et al. Human metabolic phenotypes link directly to specific dietary preferences in healthy individuals. J Proteome Res. 2007;6(11):4469-4477. doi:10.1021/pr070431h
Benton D, Williams C, Brown A. Impact of consuming a milk drink containing a probiotic on mood and cognition. Eur J Clin Nutr. 2007;61(3):355-361. doi:10.1038/sj.ejcn.1602546
Tsavkelova EA, Klimova SIu, Cherdyntseva TA, Netrusov AI. Prikl Biokhim Mikrobiol. 2006;42(3):261-268.
Gupta A, Osadchiy V, Mayer EA. Brain-gut-microbiome interactions in obesity and food addiction. Nat Rev Gastroenterol Hepatol. 2020;17(11):655-672. doi:10.1038/s41575-020-0341-5
