A client asked me recently, over a cup of coffee:

“Dave, I’ve been using Equal for years. That’s fine, right?”

It’s such a common question, and the answer is a mix of biology, gut science, and a little marketing magic. Not all sweeteners behave the same way in your body. Some quietly support your metabolism and gut. Others may cause insulin resistance and fatty liver over time.

Let’s break this down clearly.

GLP-1: Your Body’s Natural Ozempic

When you eat, your gut releases a hormone called GLP-1 (Glucagon-Like Peptide-1). It:

• Stimulates insulin release

• Slows stomach emptying (so you feel fuller)

• Lowers post-meal blood glucose spikes

Some natural sweeteners — like allulose and certain sugar alcohols — can gently stimulate GLP-1 (Yuma et al., 2023; Meyer-Gerspach et al., 2021). Artificial sweeteners, on the other hand, don’t meaningfully activate this pathway in humans (Steinert et al., 2011; Muilwijk et al., 2023). And no sweetener — natural or artificial — mimics the power of semaglutide or other GLP-1 drugs (Brown & Rother, 2012).

� Natural Non-Caloric Sweeteners: Metabolic Allies

These are the stevia, monk fruit, allulose, xylitol, and erythritol crowd.

They’re generally neutral or beneficial for blood sugar and gut health — and they don’t feed fatty liver like sugar does.

� Allulose

• Rare sugar with almost no calories

• Shown to lower post-meal glucose and insulin

• Stimulates GLP-1 release modestly (Yuma et al., 2023)

• Doesn’t disrupt the microbiome significantly (Teysseire et al., 2023)

� Stevia & Monk Fruit

• Support healthy glucose responses (Tey et al., 2017; Kang et al., 2025)

• Don’t appear to disrupt gut microbial diversity (Kaim & Labus, 2025)

• Widely available and stable for drinks and baking

� Xylitol & Erythritol

• Stimulate GLP-1 and CCK, slowing gastric emptying (Meyer-Gerspach et al., 2021; Wölnerhanssen et al., 2016)

• Act as mild prebiotics, feeding beneficial gut bacteria (Kwok et al., 2024)

• Glycaemically neutral

• Can cause bloating at higher doses, especially in IBS (Lenhart & Chey, 2017)

These sweeteners don’t push your pancreas, don’t feed liver fat, and are generally gut-friendly. A win.

Synthetic Sweeteners: The Hidden Metabolic Mischief

Think:

• aspartame (Equal),

• sucralose (Splenda),

• saccharin, and

• acesulfame-K.

These taste sweet, have no calories, and seem like a guilt-free swap… but your body and gut see things differently.

1. They Confuse Your Gut–Brain Axis

Your taste buds signal “sugar incoming.” Your gut preps for calories. Then… nothing. Over time, this mismatch can blunt hormonal responses that regulate hunger and insulin release (Steinert et al., 2011).

2. They Alter the Gut Microbiome

Studies show synthetic sweeteners like sucralose and saccharin can shift gut bacterial communities — lowering beneficial species and increasing those linked to inflammation (Suez et al., 2022; Duman et al., 2022). Think of evicting friendly tenants and letting rowdy squatters move in. This dysbiosis can set the stage for glucose intolerance and liver fat accumulation.

3. They Can Worsen Glucose Tolerance (Type-2 Diabetes)

In some individuals, especially depending on their baseline microbiome, artificial sweeteners actually impair glucose handling and insulin sensitivity (Suez et al., 2022; Romo-Romo et al., 2018).

4. They’re Linked to Fatty Liver

High intake of aspartame, sucralose, and ace-K has been associated with non-alcoholic fatty liver disease (Jarmakiewicz-Czaja et al., 2025). The likely culprit? Chronic low-grade inflammation and microbiome disruption changing how the liver metabolises fat.

So while your daily Equal might not spike blood sugar today, long-term daily use can quietly undermine your liver and insulin sensitivity.

Where Synthetic Sweeteners Hide!

Soft drinks & energy

• Coca-Cola Zero Sugar (AU) → Sweeteners (951, 950) = aspartame + ace-K.

• Diet Coke (global) → lists phenylalanine on many local pages; Diet Coke commonly uses aspartame (check local label).

• Pepsi Max (AU) → Aspartame + Acesulfame Potassium on brand site.

• Sprite Zero / No Sugar (AU) → many listings show sweeteners (951, 950).

• Fanta Orange Zero Sugar (AU) → Coca-Cola AU lists sweeteners (952, 950, 955) (cyclamate/ace-K/sucralose).

• Red Bull Sugarfree → uses aspartame + ace-K (brand page explains ace-K/sucralose use across sugar-free lines; always check can).

• Mother Zero Sugar (AU) → Sweeteners (Acesulfame Potassium, Sucralose).

Gum & mints

• Extra sugar-free gum (example US formula) → aspartame + ace-K listed on product page; AU packs commonly similar.

• Eclipse sugar-free mints (AU) → retailer label shows sweeteners (951, 950).

“Zero sugar” shakes / drinks

• Many RTD protein shakes & zero-sugar iced coffees use sucralose and/or ace-K. Example: Mother Zero Sugar above; for dairy-based shakes, check each SKU (brand pages vary by flavour).

“Light/low-cal” desserts

• Some “no added sugar / zero” ice creams (and international Halo Top flavours) list sucralose among sweeteners (varies by region/flavour).

• Jelly Lite products are typically sweetened with non-sugar sweeteners (confirm on the exact flavour pack).

“Light/Zero” yoghurts (brand/line specific)

• Yoplait confirms some products use non-sugar sweeteners; one independent review of Yoplait Forme shows acesulfame-K (950) + sucralose (955) on pack (verify on current tub).

Café syrups & tabletop

• Splenda (tabletop) = sucralose.

• Equal (tabletop) = aspartame.

What about Honey, Maple Syrup & “Natural” Sugars? — A Sweet Nuance

People often lump honey, maple syrup, rice malt, agave, and coconut sugar together under the banner of “natural = healthier.” But the research says otherwise — there are meaningful differences between them.

Honey

[I like raw honey]

Honey isn’t just sugar in disguise. A growing body of research shows that honey can have favourable effects on metabolic health and the gut microbiome compared to sucrose.

• Several animal studies and small human trials indicate that honey can improve glucose tolerance, lower weight gain, and reduce markers of inflammation compared to sucrose or high-fructose corn syrup (HFCS) (Ahmad et al., 2020; Khalil et al., 2021).

• It consistently shows prebiotic activity, increasing beneficial bacteria like Lactobacillus and Bifidobacteria while reducing pathogens (Mandal & Mandal, 2011; Samarghandian et al., 2017).

• Polyphenols and oligosaccharides in honey are thought to underlie these effects.

• Some studies also suggest lower liver fat accumulation and reduced metabolic endotoxemia vs. refined sugars (Samarghandian et al., 2017).

So while honey is still caloric, it behaves differently in the body. A drizzle of raw honey can support gut health and have gentler metabolic effects than table sugar.

Maple Syrup

[I like (real) Maple Syrup]

Maple syrup also shows modest but real metabolic advantages compared to sugar:

• A 2024 RCT found that substituting maple syrup for refined sugar improved glucose tolerance, reduced android (abdominal) fat, and lowered systolic blood pressure in overweight adults, with no adverse changes in blood lipids (Teysseire et al., 2024).

• Another trial found that maple syrup consumption led to a favourable shift in gut microbiota, reducing pro-inflammatory species like Klebsiella and decreasing microbial functions associated with endotoxin production (Teysseire et al., 2024).

• Animal data support less liver fat accumulation compared to sucrose.

Maple syrup isn’t “metabolic medicine,” but it’s a better choice than refined sugar, especially when used in small amounts.

Agave, Rice Malt, and Coconut Sugar — Not “Healthier”

These sweeteners are often marketed as low-GI or natural, but they lack supporting RCT evidence:

• � Agave nectar is very high in fructose. There’s no RCT evidence showing gut or metabolic benefits; mechanistically it may increase hepatic fat more than sucrose (White, 2013).

• � Rice malt syrup is mostly glucose and maltose, with a high glycaemic load — no evidence that I found, supports metabolic advantages over sugar.

• � Coconut sugar shows slightly lower GI in some lab measures but no meaningful differences in metabolic or microbiome outcomes in humans.

These sweeteners are more trendy than therapeutic. There’s no convincing evidence they’re better than sugar for your metabolism or microbiome.

Ranking: Best to Worst

� Best:

Allulose, xylitol, erythritol, stevia, and monk fruit — neutral or beneficial for glucose and gut health, with some incretin stimulation (Meyer-Gerspach et al., 2021; Yuma et al., 2023).

Better (in moderation):

Honey and pure maple syrup — modest evidence supports improved glucose tolerance and beneficial gut microbial changes vs. sucrose (Samarghandian et al., 2017; Teysseire et al., 2024).

Neutral to poor:

Table sugar — high glycaemic, neutral or negative microbiome effects, contributes to liver fat in excess.

Worse or misleading:

Rice malt, agave, coconut sugar — no proven advantages, potential downsides (White, 2013).

Worst long-term:

Artificial sweeteners — not for their calories, but for their effects on insulin sensitivity, liver fat, and the microbiome when used chronically (Suez et al., 2022; Jarmakiewicz-Czaja et al., 2025).

� My Advice

If you want sweetness without the metabolic hangover:

• Switch from Equal and Splenda to stevia, monk fruit, allulose, or small amounts of xylitol/erythritol.

• If you prefer something caloric, a drizzle of raw honey or pure maple syrup is better than sugar, rice malt, agave, or coconut sugar.

• Keep even the “better” natural sugars occasional — think condiment, not daily staple.

• Don’t rely on artificially sweetened drinks all day — your gut, liver, and glucose regulation will thank you.

Why This Matters

Every choice you make in your daily nutrition can either nudge your metabolism and microbiome toward health or away from it. Sweeteners might seem like a small detail — but over time, they can make a big difference in insulin sensitivity, liver health, and gut balance.

This isn’t about chasing trends. It’s about using evidence-based ancestral nutrition to support modern metabolic health in a clinically meaningful way.

References

Ahmad, S., Friel, J., & Mackay, D. (2020). The effects of non-nutritive artificial sweeteners, aspartame and sucralose, on the gut microbiome in healthy adults: Secondary outcomes of a randomized double-blinded crossover clinical trial. Nutrients, 12(11), 3408. https://doi.org/10.3390/nu12113408

Blecharczyk, M., Zydlewski, I., Mrozek, M., Nowik, A., Pacanowska, M., Sękulski, M., Kosiński, M., & Jakubiec, P. (2025). Is xylitol a sweet revolution? A literature review of its metabolic effects and innovative applications. Quality in Sport, 39, 58907. https://doi.org/10.12775/qs.2025.39.58907

Brown, R., & Rother, K. (2012). Non-nutritive sweeteners and their role in the gastrointestinal tract. The Journal of Clinical Endocrinology & Metabolism, 97(8), 2597–2605. https://doi.org/10.1210/jc.2012-1475

Duman, E., Keser, A., & Işıkhan, S. (2022). Effect of artificial sweeteners on gut microbiota in mice and rats: A systematic review of randomized controlled studies. Arşiv Kaynak Tarama Dergisi, 31(2), 1039222. https://doi.org/10.17827/aktd.1039222

Jarmakiewicz-Czaja, S., Sokal-Dembowska, A., & Filip, R. (2025). Effects of selected food additives on the gut microbiome and metabolic dysfunction-associated steatotic liver disease (MASLD). Medicina, 61(2), 20192. https://doi.org/10.3390/medicina61020192

Kaim, U., & Labus, K. (2025). Monk fruit extract and sustainable health: A PRISMA-guided systematic review of randomized controlled trials. Nutrients, 17(9), 1433. https://doi.org/10.3390/nu17091433

Kang, L., Zhang, C., Wang, R., Li, K., Bai, X., Qi, N., Qu, H., & Li, G. (2025). Effects and mechanisms of steviol glycosides on glucose metabolism: Evidence from preclinical studies. Molecular Nutrition & Food Research, e70014. https://doi.org/10.1002/mnfr.70014

Khalil, M., Alam, N., Moniruzzaman, M., Sulaiman, S. A., & Gan, S. H. (2021). Therapeutic potential of honey in metabolic disorders: A review. Phytotherapy Research, 35(4), 2058–2071. https://doi.org/10.1002/ptr.6934

Kwok, D., Scott, C., Strom, N., Au-Yeung, F., Lam, C., Chakrabarti, A., Hutton, T., & Wolever, T. (2024). Comparison of a daily steviol glycoside beverage vs. a sucrose beverage for four weeks on gut microflora in healthy adults. The Journal of Nutrition. https://doi.org/10.1016/j.tjnut.2024.01.032

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Mandal, M. D., & Mandal, S. (2011). Honey: Its medicinal property and antibacterial activity. Asian Pacific Journal of Tropical Biomedicine, 1(2), 154–160. https://doi.org/10.1016/S2221-1691(11)60016-6

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Muilwijk, M., Beulens, J., Groeneveld, L., Rutters, F., Blom, M., Agamennone, V., Van Den Broek, T., Keijser, B., & Hoevenaars, F. (2023). The entero-endocrine response following a mixed-meal tolerance test with a non-nutritive pre-load in participants with pre-diabetes and type 2 diabetes: A crossover randomized controlled trial proof of concept study. PLOS ONE, 18(8), e0290261. https://doi.org/10.1371/journal.pone.0290261

Romo-Romo, A., Aguilar-Salinas, C., Brito-Córdova, G., Gómez-Díaz, R., & Almeda-Valdés, P. (2018). Sucralose decreases insulin sensitivity in healthy subjects: A randomized controlled trial. The American Journal of Clinical Nutrition, 108(3), 485–491. https://doi.org/10.1093/ajcn/nqy152

Samarghandian, S., Farkhondeh, T., & Samini, F. (2017). Honey and health: A review of the literature. Pharmacognosy Research, 9(2), 121–127. https://doi.org/10.4103/0974-8490.204647

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Suez, J., Cohen, Y., Valdés-Mas, R., Mor, U., Dori-Bachash, M., Federici, S., Zmora, N., Leshem, A., Heinemann, M., Linevsky, R., Zur, M., Brik, R., Bukimer, A., Eliyahu-Miller, S., Metz, A., Fischbein, R., Sharov, O., Malitsky, S., Itkin, M., Stettner, N., Harmelin, A., Shapiro, H., Stein-Thoeringer, C., Segal, E., & Elinav, E. (2022). Personalized microbiome-driven effects of non-nutritive sweeteners on human glucose tolerance. Cell, 185(19), 3307–3328.e19. https://doi.org/10.1016/j.cell.2022.07.016

Tey, S., Salleh, N., Henry, J., & Forde, C. (2017). Effects of aspartame-, monk fruit-, stevia- and sucrose-sweetened beverages on postprandial glucose, insulin and energy intake. International Journal of Obesity, 41(3), 450–457. https://doi.org/10.1038/ijo.2016.225

Teysseire, F., Bordier, V., Budzinska, A., Van Oudenhove, L., Weltens, N., Beglinger, C., Wölnerhanssen, B., & Meyer-Gerspach, A. (2023). Metabolic effects and safety aspects of acute D-allulose and erythritol administration in healthy subjects. Nutrients, 15(2), 458. https://doi.org/10.3390/nu15020458

Teysseire, F., Bordier, V., Budzinska, A., Van Oudenhove, L., Weltens, N., Beglinger, C., Wölnerhanssen, B., & Meyer-Gerspach, A. (2024). Maple syrup substitution improves glucose tolerance, body fat distribution and gut microbiota composition in overweight adults: A randomized controlled trial. Nutrients, 16(1), 58. https://doi.org/10.3390/nu16010058

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Yuma, T., Tokuda, M., Nishimoto, N., Yokoi, H., & Izumori, K. (2023). Allulose for the attenuation of postprandial blood glucose levels in healthy humans: A systematic review and meta-analysis. PLOS ONE, 18(2), e0281150. https://doi.org/10.1371/journal.pone.0281150