The market for sugar alternatives has rapidly expanded as consumers look to reduce caloric intake without sacrificing sweetness. Among the most popular low-calorie substitutes, allulose and erythritol have emerged as frontrunners, each offering a distinct approach to replacing table sugar. Allulose is a “rare sugar” found in small quantities in nature, while erythritol is a sugar alcohol widely used in manufactured low-carb foods. The choice between these two depends heavily on how the body processes them, their sensory properties, and any potential health considerations. This comparison aims to detail the differences between allulose and erythritol.
How the Body Processes Allulose vs. Erythritol
These two sweeteners differ fundamentally in their chemical composition and how they are handled by the body’s metabolic pathways. Allulose is classified as a monosaccharide, structurally similar to fructose but possessing a slight difference in atomic arrangement. This structural variance is why the body absorbs 70 to 80% of consumed allulose in the small intestine but does not metabolize it for energy. Allulose provides a negligible caloric load, estimated at only 0.2 to 0.4 calories per gram, which is about one-tenth the calories of traditional sugar.
Erythritol, by contrast, is a sugar alcohol, or polyol, produced commercially through the fermentation of glucose. Approximately 90% of ingested erythritol is rapidly absorbed into the bloodstream. Once absorbed, it remains largely untouched by the body’s enzymes and is excreted unchanged through the urine. It provides a near-zero 0.24 calories per gram, and a truly zero glycemic impact. Neither allulose nor erythritol significantly raises blood glucose or insulin levels, making both suitable options for individuals monitoring their blood sugar.
Differences in Digestive Tolerance
The mechanism by which the body processes each sweetener directly influences its potential for causing digestive discomfort. As a sugar alcohol, erythritol is generally well-tolerated compared to other polyols like xylitol or sorbitol, primarily because 90% of it is absorbed before reaching the colon. However, the unabsorbed 10% that does reach the large intestine is subject to bacterial fermentation. This fermentation process produces gas and can draw water into the colon, which may lead to gastrointestinal side effects such as bloating, gas, stomach rumbling, and a laxative effect, particularly when consumed in large single doses.
Allulose is distinct because its absorption in the small intestine, followed by urinary excretion, means very little of the compound reaches the large intestine. Since it largely resists fermentation by gut bacteria, allulose typically causes significantly fewer digestive issues than sugar alcohols. The few reported instances of discomfort with allulose usually occur only after extremely high consumption, and the reaction is not due to fermentation but rather the non-metabolized substance passing through the digestive tract. For individuals with a sensitive digestive system, this difference in tolerance profile may make allulose a more comfortable choice for daily use.
Flavor, Texture, and Culinary Performance
The experience of using these sweeteners in food and beverages presents notable differences. Allulose is generally praised for having a clean, sugar-like taste without the noticeable aftertaste often associated with other substitutes. It is about 70% as sweet as table sugar, meaning a slightly higher quantity is needed to match the sweetness of sucrose. A major advantage of allulose in the kitchen is its ability to caramelize and brown when heated, functioning similarly to sugar in baked goods and sauces.
Erythritol is also around 60 to 80% as sweet as sugar, but it is known to produce a distinct cooling sensation on the tongue. This is a characteristic physical property of the compound that some people find unpleasant, though it can be masked when blended with other sweeteners. In culinary applications, erythritol does not caramelize and has a tendency to recrystallize upon cooling. This crystallization can result in a gritty texture in baked goods or frozen desserts, limiting its versatility compared to allulose.
Overall Health Implications and Comparative Summary
The overall health profile of both sweeteners is generally positive, especially as alternatives to high-calorie sugars. Allulose is widely recognized as safe (GRAS) by the U.S. Food and Drug Administration and has not been linked to any major health warnings. Some preliminary research suggests allulose may even offer benefits, such as a potential for lowering overall blood sugar and protecting pancreatic cells.
Erythritol’s safety profile has recently come under scrutiny due to a study suggesting a potential link between high blood levels of the sweetener and an increased risk of blood clotting, heart attack, or stroke. This area remains one of ongoing research and debate, and the study did not establish a direct cause-and-effect relationship between dietary consumption and risk. The finding highlights the need for continued investigation into the long-term effects of sugar alcohols.
When comparing the two, allulose offers superior gastrointestinal comfort and behaves more like sugar in baking, making it the preferred choice for those with GI sensitivity or a need for sugar-like culinary properties. Erythritol remains an excellent option for those prioritizing the lowest possible calorie count and glycemic impact, as its energy content is virtually zero. Ultimately, the “better” sweetener depends on whether the user values culinary performance and digestive comfort (allulose) or absolute calorie and cost minimization (erythritol).