Quick Answer: Clinical studies suggest that allulose has minimal effects on blood glucose and insulin when consumed on its own. When used in place of sugar or consumed alongside carbohydrate-containing foods, research suggests allulose may help reduce the size of the post-meal blood sugar rise. With only 0.4 calories per gram, allulose provides sweetness with a fraction of the calories of sugar.
If you're working on your blood sugar, "sugar swap" advice can feel overwhelming. Not all sweeteners act the same way in your body, especially when you look closely at blood glucose and insulin responses after a meal. Allulose is one of the most interesting sweeteners to emerge from recent research. It tastes like sugar, behaves similarly to sugar in recipes, but shows a very different pattern in blood sugar studies.
What Is Allulose?
Allulose (also called D-allulose or D-psicose) is a rare sugar found naturally in small amounts in foods such as figs, raisins, and maple syrup. Chemically, it resembles fructose, but a small structural difference changes how the body processes it.
Because of this, allulose provides approximately 70% of the sweetness of table sugar while contributing only around 0.4 calories per gram, compared with 4 calories per gram for sugar. Human studies suggest that most absorbed allulose is excreted unchanged in the urine rather than being used as an energy source (1,2).
How Allulose Differs From Regular Sugar
From both a labeling and physiological perspective, allulose behaves differently from sucrose:
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Very low calories: FDA guidance allows allulose to be labeled as 0.4 kcal/g.
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Excluded from Total and Added Sugars: FDA guidance allows allulose to be excluded from the "Total Sugars" and "Added Sugars" lines on Nutrition Facts labels.
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Minimal impact on blood sugar: Human studies suggest allulose produces little to no rise in blood glucose when consumed by itself.
How Many Calories Does Allulose Have?
One reason allulose has attracted attention is its unusually low calorie content.
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Sugar provides approximately 4 calories per gram.
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Allulose provides approximately 0.4 calories per gram.
This means allulose delivers sweetness with roughly 90% fewer calories than sugar while maintaining many of sugar's functional properties in foods and beverages.
Does Allulose Raise Blood Sugar?
One of the most common questions about allulose is whether it raises blood glucose levels. Clinical studies suggest that allulose has minimal effects on blood glucose when consumed on its own, which helps explain why it is often discussed as a lower-glycaemic alternative to traditional sugars. Unlike regular sugar, it does not produce the same post-meal rise in blood glucose (3). For people looking to moderate post-meal blood sugar responses, this is one of the most interesting characteristics of allulose.
What Do The Clinical Studies Show?
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Systematic Review and Meta-Analysis in Healthy Adults
A 2023 systematic review and meta-analysis pooled multiple clinical studies in healthy adults investigating allulose consumed with carbohydrate-containing meals 3. Across studies, doses of 5–10 g of allulose were associated with smaller post-meal blood glucose responses compared with control conditions. The authors concluded that allulose may help support a healthier post-meal glucose response, although most studies evaluated short-term, single-meal effects.
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Randomized Crossover Trial in Healthy Adults
In a double-blind, randomized crossover trial, 30 adults without diabetes consumed a sucrose drink with or without allulose (2.5–10 g) (4). Higher doses of allulose (7.5–10 g) were associated with smaller post-meal glucose and insulin responses compared with sucrose alone, suggesting allulose may help moderate post-meal glucose excursions when consumed alongside sugar.
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Allulose Alone vs Allulose Plus Sucrose
A randomized controlled trial in 14 adults without diabetes compared allulose alone, allulose combined with sucrose, and sucrose alone (5). Allulose produced minimal changes in blood glucose when consumed by itself, while the combination of allulose and sucrose resulted in smaller glucose and insulin responses than sucrose alone.
What About People With Higher Blood Sugar?
A 2024 meta-analysis pooled six clinical studies involving 126 adults with type 2 diabetes. Overall, allulose was associated with smaller post-meal glucose responses and less time spent above target glucose ranges. The authors concluded that allulose may be a useful dietary ingredient for supporting healthy post-meal glucose management, while noting that larger and longer-term studies are still needed (6).
Similar findings were reported in a small 10-day pilot study conducted during Ramadan fasting, where consuming 8.5 g of allulose before the evening meal (iftar) was associated with smaller post-meal glucose excursions and more time spent within target glucose ranges (7).
How Might Allulose Work?
Researchers are still investigating the exact mechanisms involved, but several possibilities have been proposed:
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Slower carbohydrate digestion: Allulose may influence enzymes involved in carbohydrate breakdown (4).
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Changes in sugar absorption: Allulose appears to share some intestinal transport pathways with glucose and fructose.
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Effects on glucose metabolism: Animal studies suggest allulose may influence how the body handles glucose after meals (8).
While more research is needed, these mechanisms may help explain why allulose produces a different blood glucose response than traditional sugars.
How to Use Allulose in Everyday Life
Replacing regular sugar with allulose can be one practical strategy for reducing overall sugar intake. Ways to use allulose include:
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Sweetening coffee and tea.
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Adding sweetness to yogurt or oats.
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Using it in baking and cooking.
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Including it in homemade snacks and desserts.
Many clinical studies investigating blood sugar responses have used approximately 5–10 g of allulose alongside carbohydrate-containing meals.
Safety and Tolerability
Allulose has been reviewed as Generally Recognized as Safe (GRAS) for use in foods and beverages. Most people tolerate typical serving sizes well. At higher intakes, some individuals may experience mild gastrointestinal symptoms such as bloating, gas, or loose stools. As with any new ingredient, it can be helpful to start with smaller amounts and increase gradually according to personal tolerance.
Take-Home Message
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Allulose provides sweetness with only 0.4 calories per gram.
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Clinical studies suggest allulose has minimal effects on blood glucose and insulin when consumed on its own.
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Research suggests 5–10 g of allulose consumed with carbohydrate-containing foods may help support a smaller post-meal glucose response.
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Allulose is widely considered keto friendly and is commonly used as an alternative to sugar in lower-carbohydrate eating patterns.
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Allulose is not a medication, but it may be a useful sugar alternative as part of an overall healthy diet and lifestyle.
FAQs
Does allulose spike blood sugar?
Research suggests allulose has minimal effects on blood glucose when consumed on its own and may help support a smaller post-meal glucose response when consumed alongside carbohydrate-containing foods.* Individual responses may vary.
Does allulose affect insulin?
Clinical studies suggest allulose has minimal effects on insulin when consumed alone. Some studies have also reported lower post-meal insulin responses when allulose is consumed with carbohydrate-containing foods compared with control conditions.*
What Is the glycemic index of allulose?
Allulose has a glycemic index close to zero because it produces minimal changes in blood glucose when consumed on its own.* This makes it a lower-glycemic alternative to traditional sugars.
Is allulose keto-friendly?
Yes. Allulose is widely considered keto friendly because it contributes very few calories and has minimal effects on blood glucose and insulin in human studies.*
Does allulose count as carbs?
Yes. Allulose is included in the Total Carbohydrate value on Nutrition Facts labels. However, FDA guidance allows it to be excluded from the Total Sugars and Added Sugars lines.
Do you subtract allulose from carbs?
Many people following low-carbohydrate or ketogenic diets choose to subtract allulose when calculating net carbs. However, approaches can vary depending on individual dietary preferences and goals.
Reviewed by Dr. Ilma Imtiaz
References
1. US Food and Drug Administration. Guidance for Industry: The Declaration of Allulose and Calories from Allulose on Nutrition and Supplement Facts Labels. FDA; 2019, updated 2023. https://www.fda.gov/regulatory-information/search-fda-guidance-documents/guidance-industry-declaration-allulose-and-calories-allulose-nutrition-and-supplement-facts-labels
2. US Food and Drug Administration; Center for Food Safety and Applied Nutrition. The Declaration of Allulose and Calories from Allulose on Nutrition and Supplement Facts Labels: Guidance for Industry. FDA; 2019. https://www.fda.gov/regulatory-information/search-fda-guidance-documents/guidance-industry-declaration-allulose-and-calories-allulose-nutrition-and-supplement-facts-labels
3. Tani Y, Tokuda M, Nishimoto N, Yokoi H, Izumori K. Allulose for the attenuation of postprandial blood glucose levels in healthy humans: a systematic review and meta-analysis. PLoS One. 2023;18(4):e0281150. https://doi.org/10.1371/journal.pone.0281150
4. Franchi F, Yaranov DM, Rollini F, et al. Effects of D-allulose on glucose tolerance and insulin response to a standard oral sucrose load: results of a prospective, randomized, crossover study. BMJ Open Diabetes Res Care. 2021;9(1):e001939. https://doi.org/10.1136/bmjdrc-2020-001939
5. Jenkins A, Au-Yeung F, Prancevic S, Campbell J, Vissers E, Wolever T. Comparison of postprandial glycemic and insulinemic response of allSWEET®, non-GMO allulose, consumed alone or when consumed with sucrose: a randomized, controlled trial. Curr Dev Nutr. 2022;6(suppl 1):445. https://doi.org/10.1093/cdn/nzac057.011
6. Ayesh H, Suhail S, Ayesh S. Impact of allulose on blood glucose in type 2 diabetes: a meta-analysis of clinical trials. Metabolism Open. 2024;24:100329. https://doi.org/10.1016/j.metop.2024.100329
7. Japar S, Fukunaga K, Kobayashi T, et al. A pilot study on the effect of D-allulose on postprandial glucose levels in patients with type 2 diabetes mellitus during Ramadan fasting. Diabetol Metab Syndr. 2022;14(1):86. https://doi.org/10.1186/s13098-022-00856-3
8. Shintani T, Yamada T, Hayashi N, et al. Rare sugar syrup containing D-allulose but not high-fructose corn syrup maintains glucose tolerance and insulin sensitivity partly via hepatic glucokinase translocation in Wistar rats. J Agric Food Chem. 2017;65(13):2888-2894. https://doi.org/10.1021/acs.jafc.6b05627
These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.
