Allulose is a low-calorie sugar that tastes and behaves like regular sugar but provides only 0.4 calories per gram, about one-tenth the calories of table sugar. It’s found naturally in tiny amounts in foods like wheat, figs, and processed sugarcane, which is why it’s sometimes called a “rare sugar.” Unlike artificial sweeteners, allulose is a real sugar molecule. Your body just handles it very differently than it handles the sugar in your coffee.
How Allulose Compares to Regular Sugar
Allulose has the same molecular formula as fructose (the sugar in fruit), but a small structural difference at two of its carbon atoms changes everything about how your body processes it. That tiny tweak means your enzymes largely ignore it. Most of the allulose you eat gets absorbed in your small intestine through the same transporter that handles fructose, but instead of being broken down for energy, it passes through your body and is excreted in urine without being metabolized.
The result: allulose delivers about 70% of the sweetness of table sugar with a fraction of the metabolic impact. It browns in the oven, dissolves in liquids, and creates that same mouthfeel you expect from sugar. That combination of real-sugar behavior and near-zero caloric impact is what makes it increasingly popular in packaged foods, baked goods, and ice cream.
What It Does to Blood Sugar
Allulose doesn’t just avoid raising blood sugar on its own. It may actively blunt the blood sugar spike from other sugars eaten at the same time. In a crossover study published in BMJ Open Diabetes Research & Care, adding 7.5 to 10 grams of allulose to 50 grams of regular sugar significantly reduced blood glucose levels 30 minutes after eating. The 10-gram dose also reduced the overall glucose spike over the full measurement period. In practical terms, that’s roughly two teaspoons of allulose taken alongside a sugar-containing meal or drink.
This effect makes allulose particularly interesting for people managing blood sugar levels, though it’s worth noting that most studies have been relatively small and short-term.
FDA Labeling and Safety Status
The FDA has accepted multiple Generally Recognized as Safe (GRAS) notifications for allulose, meaning it’s approved for use in food. More unusually, the FDA also gave allulose a special labeling advantage: manufacturers can exclude it from both the “Total Sugars” and “Added Sugars” lines on nutrition facts panels. That’s a distinction no other sugar has received. The reasoning is that allulose doesn’t behave like sugar in the body, so counting it alongside sucrose would be misleading.
When allulose does appear in the calorie count, the FDA advises using 0.4 calories per gram. For comparison, regular sugar provides 4 calories per gram. So a product sweetened with allulose will show dramatically fewer calories and zero added sugars on the label, even though allulose is technically a sugar by chemical definition.
Digestive Side Effects
Like sugar alcohols such as erythritol and xylitol, allulose can cause digestive discomfort if you eat too much at once. The threshold varies by body size. A tolerance study found that a single dose up to 0.4 grams per kilogram of body weight was well tolerated, with no severe symptoms. For someone weighing about 130 pounds (60 kg), that works out to roughly 24 grams in one sitting, or about six teaspoons.
Push past that, and the picture changes. At 0.5 grams per kilogram, participants experienced severe diarrhea. For daily intake spread across meals, the ceiling was higher: up to 0.9 grams per kilogram per day (about 54 grams for a 130-pound person) before symptoms like nausea, abdominal pain, and diarrhea became a problem. If you’re new to allulose, starting with smaller amounts and increasing gradually is the practical move.
Effects on Dental Health
One of the clearest advantages allulose has over sugar is what it does (or doesn’t do) to your teeth. The bacteria that cause cavities, particularly Streptococcus mutans, thrive on regular sugar. They consume it, produce acid, and build sticky biofilms on tooth surfaces. Allulose essentially starves this process.
In lab testing, allulose reduced acid production by 98 to 99% compared to sucrose within 30 minutes. The pH of bacterial cultures stayed above 5.0, the critical threshold below which tooth enamel starts to dissolve. Bacteria exposed to allulose also failed to build the dense, dome-shaped biofilm structures that characterize cavity-causing plaque. Instead, allulose-treated biofilms looked similar to those grown with xylitol or erythritol, two sweeteners already recognized for their dental benefits. The genes responsible for producing lactic acid and building the sticky matrix of dental plaque were significantly less active in the presence of allulose.
How It’s Made Commercially
Although allulose exists naturally in wheat and certain other foods, the concentrations are far too low for commercial extraction. Instead, manufacturers produce it by converting fructose (typically from corn) using a specific enzyme. This process rearranges the molecular structure at two carbon atoms, transforming common fructose into the rare sugar. The result is chemically identical to the allulose found in nature.
You’ll find allulose sold as a standalone sweetener in granulated and liquid forms, and increasingly as an ingredient in protein bars, low-sugar ice creams, soft drinks, and baked goods. Because it behaves so much like sugar in cooking, caramelizing and providing bulk, it’s often easier to substitute in recipes than stevia or monk fruit, which require different ratios and can leave aftertastes that allulose generally avoids.