This New Super-Sweet Protein Sweetener Won’t Spike Insulin

Imagine a pinch of white powder, smaller than a grain of salt, delivering the sweetness of a spoonful of sugar without stirring your blood sugar. That is the claim behind a new protein-based sweetener called sweelin, developed by Amai Proteins, which the company says is roughly 3,500 times sweeter than sucrose by weight.

Sweet proteins are not a lab-fantasy. They grow in rare tropical fruits and evolved, perhaps, to lure fruit-eating animals. One such fruit, the serendipity berry (Dioscoreophyllum cumminsii) from West and Central African rainforests, holds one of nature’s most potent sweet molecules. Amai’s team used that natural blueprint, then ran it through AI-guided design to refine a stable, food-ready powder.

What makes sweelin intriguing for scientists and consumers is not only its intensity but its reported metabolic quietness. In a small double-blind, randomized trial conducted at Tel Aviv Sourasky Medical Center and funded by Amai, 19 volunteers had their blood glucose, insulin, and GLP-1 tracked for two hours after drinking a beverage containing a single high dose of sweelin. The same participants later repeated the test with stevia and with dextrose on separate visits. Participants and study staff were blinded to which sweetener was served.

Results, published in Food Chemistry, showed sweelin produced an overall glucose response roughly 31 times lower than dextrose and an insulin response about 81 times lower. It performed similarly to stevia across the two-hour window and, notably, did not trigger a rise in circulating GLP-1, a hormone linked to post-meal metabolic signaling. Those findings matter most for people with type 2 diabetes, prediabetes, or obesity, where postprandial glucose spikes contribute to long-term cardiovascular risk.

Fig. 1. Incremental levels of glucose (A) and insulin (B) after consumption of the test beverages. 

Still, the story is not over. The trial was short and small. Nineteen people do not represent a global population with varied diets, gut microbiomes, medications, or comorbidities. Long-term safety, effects on hunger and appetite, interactions with gut hormones beyond GLP-1, and potential rare side effects remain unanswered. The study’s funding source—Amai—also means independent replication will be important before declaring metabolic neutrality.

Practical features of sweelin are already being highlighted. The sweetener is a dissolvable white powder, reportedly so potent that less than 3 mg is needed for a typical iced tea serving. It withstands heat, which means it can be used in cooking and some baking, and Amai suggests it can replace up to 70 percent of sugar in certain recipes. Earlier this year, the US Food and Drug Administration said it had no questions for Amai regarding the company’s safety dossier, and sweelin is now available as a sugar substitute in the US, Singapore, and Israel.

Why does this matter beyond novelty? Because replacing added sugars without creating metabolic disruption is a puzzle nutrition science has long tried to solve. Many calorie-free or low-calorie sweeteners skirt immediate glycemic effects but still carry unanswered questions: do they change appetite, alter the gut microbiome, or have subtle hormonal effects that accumulate over years? A sweet protein that genuinely leaves blood glucose and insulin untouched would be valuable, especially if it keeps food taste and texture intact.

Evidence so far is an encouraging first chapter, not a finished book. Larger, longer trials across different age groups, ethnicities, and metabolic conditions are needed. Independent labs should test for off-target effects and verify the absence of GLP-1 activation and other hormonal signals. Consumers and clinicians will want to know how sweelin behaves when combined with real meals, when used chronically, and when taken alongside common medications for diabetes and cardiovascular disease.

For now, sweelin is a reminder that nature still holds surprising tools and that modern biotechnology can reshape them into ingredients for everyday life. A tiny scoop of powder could someday be a harmless way to cut sugar, or it could reveal new complexities about how sweetness talks to our bodies. Which path unfolds will depend on the science we choose to do next.