Erythritol does not spike insulin. In human studies across lean, obese, and diabetic subjects, doses ranging from 20 to 75 grams produced no measurable change in blood insulin levels. On a scale where glucose scores 100, erythritol has a glycemic index of 0 and an insulinemic index of just 2, making it essentially neutral for blood sugar and insulin.
What Happens When You Consume Erythritol
Erythritol behaves differently from most other sweeteners and sugar alcohols. Nearly all of it is absorbed in your small intestine, but your body doesn’t metabolize it. It passes through your bloodstream and is excreted unchanged in your urine. Because it’s never broken down into glucose or processed as fuel, it doesn’t trigger the metabolic signals that tell your pancreas to release insulin.
In a randomized controlled trial published in Nutrients, researchers gave participants erythritol, sucrose, sucralose, or plain water and then measured glucose and insulin responses. Sucrose caused a significant rise in both blood sugar and insulin. Erythritol behaved no differently from tap water. The insulin changes after erythritol were statistically indistinguishable from drinking plain water at every time point measured.
How Erythritol Compares to Other Sugar Alcohols
Not all sugar alcohols are created equal when it comes to insulin. Xylitol, one of the most common alternatives, does cause a small increase in both blood glucose and insulin. Maltitol has an even higher glycemic impact. Erythritol stands out in this category because its insulinemic index of 2 is the lowest among sugar alcohols, essentially flat compared to the glucose baseline of 100.
A review in Cardiovascular Research summarized it plainly: while consumption of erythritol has no impact on plasma glucose and insulin levels, xylitol leads to a small increase. If your primary concern is avoiding an insulin response, erythritol is the cleanest option in the sugar alcohol family.
It Does Trigger Gut Hormones
Here’s where things get more nuanced. Erythritol doesn’t raise insulin, but it does stimulate the release of several gut hormones. A pilot dose-ranging study found that erythritol causes a dose-dependent increase in three satiety hormones: CCK, GLP-1, and PYY. These are the hormones that slow stomach emptying and help you feel full.
GLP-1 is particularly interesting because it’s the same hormone targeted by medications like semaglutide. You might expect that boosting GLP-1 would indirectly raise insulin, since GLP-1 normally amplifies insulin release in response to glucose. But the same study found no effect on insulin, glucagon, or another incretin hormone called GIP. The likely explanation is that GLP-1 primarily boosts insulin secretion when blood glucose is already elevated. Since erythritol doesn’t raise blood sugar, the GLP-1 release doesn’t translate into insulin secretion.
Does Erythritol Break a Fast
For people practicing intermittent fasting, the insulin question is really about whether erythritol disrupts the metabolic state of fasting. Based on the evidence, it doesn’t appear to. With an insulinemic index of 2 and no measurable effect on blood glucose or insulin in human trials at doses up to 75 grams, erythritol is unlikely to interfere with the insulin-related benefits of fasting like fat burning or ketosis.
Some people worry about a “cephalic phase” insulin response, where the sweet taste alone signals your brain to release a small burst of insulin in anticipation of incoming sugar. Research on this effect with non-nutritive sweeteners found no cephalic phase insulin release from sweet taste stimulation alone. The sweetness of erythritol on your tongue doesn’t appear to trick your pancreas into responding.
Potential Effects on Insulin Sensitivity Over Time
Beyond the immediate insulin response, there’s some evidence that erythritol may actually support better insulin sensitivity in the long run. In animal studies, erythritol administration increased the production of short-chain fatty acids in the gut, even though only a small fraction (less than 10%) of ingested erythritol reaches the large intestine. That small amount gets fermented by gut bacteria into compounds like acetic acid, propanoic acid, and butanoic acid.
These short-chain fatty acids activated receptors in fat tissue that appear to improve insulin signaling. Mice on a high-fat diet that received erythritol showed reduced obesity, improved glucose tolerance, and less fat accumulation in the liver. The mechanism involves the short-chain fatty acids stimulating specific receptors that help regulate how fat cells respond to insulin, essentially counteracting the insulin resistance that a high-fat diet normally causes. This research is in animals, so the direct relevance to humans isn’t settled, but the direction of the effect is favorable.
The Cardiovascular Concern Worth Knowing About
While erythritol gets a clean bill on insulin, a 2023 study in Nature Medicine raised a separate flag. Researchers found that high blood levels of erythritol were associated with increased risk of cardiovascular events like heart attack and stroke. In a small pilot trial, healthy volunteers who consumed erythritol had elevated plasma levels for more than two days, reaching concentrations that enhanced platelet reactivity and clot formation in lab and animal studies.
This doesn’t change the insulin story, but it’s relevant context. Erythritol’s long persistence in your bloodstream, the same trait that makes it insulin-neutral (your body doesn’t break it down), may be what creates the clotting concern. The research is still early, and the clinical significance for typical consumers isn’t fully established, but it’s a reason some cardiologists have started paying closer attention to this sweetener.