You’ve Been Using the Wrong Sweetener — Fat Cell Scientist Explains Why

DeLauer walks through each sweetener's metabolic fate and practical downsides. Allulose and erythritol are primarily urinated out, causing no insulin response. Stevia and monk fruit are natural and benign. Aspartame breaks down into amino acids. Maltitol creates an osmotic gradient in the gut, pulling water and causing diarrhea. Sucralose may cross the blood-brain barrier. He personally follows this hierarchy, choosing Diet Dr. Pepper (aspartame) over zero-sugar versions (sucralose).

DeLauer explains that aspartame simply breaks down into amino acids and is safe for the vast majority, while sucralose has some evidence of crossing the blood-brain barrier, giving him pause. He personally finds sucralose too sweet and prefers the taste of aspartame-sweetened Diet Dr. Pepper. He notes that 'zero' branded sodas typically use sucralose, while 'diet' versions use aspartame.

DeLauer praises Seed for their honesty in publishing trials even when results aren't favorable, and their customer service. He says it's the only probiotic he uses. He contrasts it with the common 'supplement company sham' perception, arguing that probiotics are among the most vetted supplements but most fail due to gut destruction. Seed's technology and clinical transparency set it apart.

DeLauer begins by listing the major sweeteners: sucralose, aspartame, and the sugar alcohols xylitol, maltitol, erythritol. He immediately notes they are not equal. He explains that erythritol is mostly urinated out, while maltitol (or mannitol) can actually be absorbed and trigger an insulin response, and xylitol is substantially better. Maltitol, however, often doesn't leave the gut; it stays in the intestines, creates an osmotic gradient, and pulls in water, leading to the infamous 'sugar-free gummy bear' explosive diarrhea. He shares a personal story of a family member who ate Hershey's sugar-free chocolate with maltitol before a dinner cruise and suffered stomach distress. He concludes that while maltitol is metabolically inert, the social cost is too high. He then ranks allulose first, stevia and monk fruit as 'perfectly benign,' erythritol as the best sugar alcohol, aspartame as no problem (metabolized to amino acids), and sucralose with caution due to speculative blood-brain barrier evidence. He personally avoids sucralose in diet sodas, preferring aspartame-sweetened Diet Dr. Pepper.

DeLauer addresses the fear head-on: the studies showing aspartame causes cancer used a rodent model genetically inclined to develop cancer and gave them the equivalent of 28 cans of caffeinated soda a day. He counters that if you gave an animal that much sugar, they would not only get cancer but also become obese and diabetic. He states aspartame is 'among the most simple' because it gets metabolized into amino acids—phenylalanine and aspartic acid—and as long as a person doesn't have the rare phenylalanine enzymatic deficiency (phenylketonuria), there is no problem. The vast majority of people do not have this deficiency. Thus, he considers aspartame safe and unworthy of the bad press.

DeLauer notes that while the research is speculative and lacks real evidence in humans, the little bit of evidence showing sucralose's ability to cross the blood-brain barrier is enough to give him pause. He doesn't claim it's dangerous, but it's the one sweetener he looks at with 'a little more caution.' This concern, combined with his personal taste preference (he finds sucralose too sweet), leads him to avoid it in diet sodas. He specifically chooses Diet Dr. Pepper (aspartame-sweetened) over Dr. Pepper Zero (sucralose-sweetened).

DeLauer describes the mechanism: maltitol doesn't leave the gut; it stays in the intestines and creates an osmotic gradient, pulling in water. This leads to the infamous 'explosive' diarrhea documented in Amazon reviews of sugar-free gummy bears. He shares a story of a family member who, after losing 70 pounds on a low-carb diet, was excited to find Hershey's sugar-free chocolate made with maltitol. DeLauer read the label and declined. The family member ate a few before a dinner cruise and soon experienced stomach distress, anticipating 'Pompeii about to erupt.' DeLauer concludes that even though maltitol is metabolically inert, the social cost—'you can't go out with friends and be in polite society'—makes it rank very low.