Below is the full customer-facing redraft, using the current Trehalose UK style: clear and commercially useful, but careful not to turn research findings into unauthorised health claims. Body citations are numbers only; all source links are confined to the references; and every internal or external link is bold. Pasted text.txtTXT
Trehalose and Blood Sugar: What Does the Research Show?
Trehalose is a carbohydrate made from two glucose molecules.
Like other digestible carbohydrates, it ultimately provides glucose to the body. Foods containing trehalose in Great Britain are therefore required to carry the statement:
“Trehalose is a source of glucose.”[1]
What makes trehalose particularly interesting is the way that glucose becomes available.
Before trehalose can be absorbed, an intestinal enzyme called trehalase must first split the molecule into its two constituent glucose molecules.[2]
Human studies consistently show that this additional digestive step produces a very different response from consuming the same quantity of free glucose.
Compared with glucose, trehalose produces a slower and substantially lower rise in blood glucose, together with a smaller insulin response.[2–5]
That distinctive metabolic profile is one of the reasons trehalose has attracted interest in food science, carbohydrate research and sports nutrition.
How Is Trehalose Digested?
Glucose is a monosaccharide.
Once it reaches the small intestine, very little digestion is required before it can be absorbed into the bloodstream.
Trehalose is different.
It consists of:
glucose + glucose
joined by a distinctive α,α-1,1 glycosidic bond.
Before those glucose molecules can be absorbed, trehalase must break that bond.[2]
The sequence is therefore:
Trehalose → digestion by trehalase → two glucose molecules → absorption
rather than:
Glucose → absorption
This helps explain why trehalose still provides genuine carbohydrate energy while producing a more gradual post-meal glucose response.
For more on its structure and properties, see What Is Trehalose? →.
The 25g Trehalose vs Glucose Study
One of the clearest human studies compared 25 g of trehalose with the same quantity of glucose in 20 healthy adults.[2]
Each participant consumed both carbohydrates on separate occasions, allowing researchers to compare their individual responses directly.
The differences were substantial.
| Measure | 25 g glucose | 25 g trehalose |
|---|---|---|
| Peak blood glucose | 154 mg/dL | 111 mg/dL |
| 2-hour glucose response | 3,185 | 1,201 |
| Peak insulin | 38.1 µIU/mL | 15.5 µIU/mL |
| 2-hour insulin response | 1,709 | 590 |
Blood glucose and insulin were both significantly lower during the first hour following trehalose compared with glucose.[2]
Across the full two-hour period:
- the glucose response to trehalose was 38% of that produced by glucose
- the insulin response was 36% of that produced by glucose.[2]
This provides some of the clearest human evidence for the distinctive metabolic behaviour of trehalose.
Where Does the Often-Quoted “GI 38” Come From?
A glycaemic-index figure of around 38 is frequently associated with trehalose.
There is a genuine experimental basis for this number.
In the 25 g crossover study, researchers calculated the two-hour blood-glucose response to trehalose relative to the response produced by glucose.
The average was:
38%.[2]
The authors noted that this relative response is conceptually similar to the calculation used for glycaemic index.
However, the experiment used 25 g of carbohydrate rather than the 50 g available-carbohydrate load normally associated with standard GI testing.[2]
For that reason, the clearest way to present the result is:
In a controlled human study, 25 g of trehalose produced 38% of the two-hour blood-glucose response produced by the same quantity of glucose.[2]
That is a directly measured result and avoids treating “GI 38” as a universal value applying to every food, dose and circumstance.
The Insulin Response Is Also Much Lower Than with Glucose
Blood glucose is only one part of the metabolic response to carbohydrate.
As glucose enters the bloodstream, insulin is released to help tissues take it up and use or store it.
In the same 25 g study, peak insulin concentrations were:
- 38.1 µIU/mL following glucose
- 15.5 µIU/mL following trehalose.[2]
Across the full two-hour period, the total insulin response to trehalose was approximately 36% of the response to glucose.[2]
Researchers also measured GIP, a gut hormone involved in stimulating insulin secretion after food consumption.
Trehalose produced a substantially smaller GIP response than glucose.[2]
Together, these measurements support the same overall picture: trehalose is ultimately converted into glucose, but it reaches the body differently from free glucose.
Larger Doses Show the Same General Pattern
The effect is not confined to a 25 g serving.
A randomised, double-blind crossover trial involving 21 obese men compared drinks providing 75 g of carbohydrate.[3]
Trehalose-containing drinks produced overall glucose and insulin responses approximately 20–35% lower than the glucose control.[3]
The study population and experimental design differed from the 25 g trial, but the direction of the result was consistent.
Even at the substantially larger carbohydrate load, trehalose produced a less pronounced glycaemic and insulinaemic response than free glucose.
What Happens When Trehalose Is Eaten with Food?
Carbohydrates are rarely consumed as isolated drinks.
A Maastricht University study therefore examined trehalose both:
- as a carbohydrate drink
- as part of a standardised mixed meal.[4]
Trehalose again produced lower glucose and insulin responses than glucose.[4]
When incorporated into the mixed meal, peak blood glucose remained lower with trehalose, while both peak insulin and overall insulin exposure were also reduced.[4]
This is particularly relevant to food formulation because it demonstrates that the distinctive response to trehalose is not confined to an isolated fasting carbohydrate test.
The difference was also observed when trehalose formed part of a mixed meal.
Evidence in People with Impaired Glucose Tolerance
Researchers subsequently conducted a related study in people with impaired glucose tolerance.[5]
Once again, trehalose produced lower post-meal glucose and insulin responses than rapidly absorbed glucose.[5]
Across studies involving healthy adults, overweight participants and people with impaired glucose tolerance, the acute human evidence therefore shows a notably consistent pattern:
Trehalose is digested into glucose, but the resulting rise in circulating glucose and insulin is slower and lower than following an equivalent amount of free glucose.[2–5]
Trehalose Is Still a Source of Glucose
The distinction is important.
Trehalose is not a zero-carbohydrate sweetener.
It is not a non-caloric sugar substitute.
And it does not prevent blood glucose from rising.
TREHA® is a genuine carbohydrate made from two glucose molecules and contributes broadly similar energy per gram to conventional digestible sugars.
Its distinctive characteristics include:
- about 40% of the sweetness of ordinary sugar
- two glucose molecules per trehalose molecule
- digestion by the intestinal enzyme trehalase
- slower glucose availability than free glucose
- a substantially smaller acute glucose and insulin response than equivalent glucose loads in human studies.[2–5]
This makes trehalose very different from both free glucose and non-caloric sweeteners.
Trehalose vs Ordinary Sugar
Sucrose and trehalose are both disaccharides, but their structures are different.
Sucrose consists of:
glucose + fructose
whereas trehalose consists of:
glucose + glucose.
Their molecular bonds are also different, meaning that they require different digestive enzymes.
This is one reason sugars should not be treated as metabolically identical simply because they all contain carbohydrate.
Trehalose also has substantially lower sweetness — about 40% as sweet as sucrose — while retaining many of the functional properties associated with real sugars.
For a broader comparison, see Trehalose vs Sugar: What's the Difference? →.
What About Regular Trehalose Consumption?
Most of the clearest evidence concerns the immediate response after consuming trehalose.
Researchers have also investigated what happens when small amounts are consumed regularly over several weeks.
10g per Day for 12 Weeks
A double-blind study involving 34 adults with a BMI of at least 23 compared:
- 10 g trehalose per day
- 10 g sucrose per day
for 12 weeks.[6]
After 12 weeks, participants receiving trehalose showed a significant reduction from their own baseline in blood glucose measured two hours after an oral glucose-tolerance test.[6]
Subgroup analysis also identified differences in several other measurements among participants with higher levels of trunk fat.[6]
These results extended the research beyond single-dose experiments, although they should be interpreted separately from the much stronger acute evidence comparing the immediate response to trehalose and glucose.
3.3g per Day
A later double-blind randomised trial studied 50 healthy adults consuming:
- 3.3 g trehalose per day
- 3.3 g sucrose per day
for 78 days.[7]
Overall changes in body composition and routine blood measurements were similar between the groups.
However, among participants who began with relatively high post-meal glucose within the normal range, two-hour glucose following a glucose challenge was lower in the trehalose group than in the sucrose group.[7]
The study therefore adds another piece to the longer-term research, while reinforcing that these effects are not as straightforward or universal as the acute trehalose-versus-glucose response.
What Does Research in Type 2 Diabetes Show?
A 2023 pilot randomised controlled trial studied 40 adults with type 2 diabetes who consumed either:
- 3.3 g trehalose per day
- 3.3 g sucrose per day
for 12 weeks.[8]
The trehalose group showed a reduction in C-reactive protein compared with the sucrose group.[8]
However, there were no significant between-group differences in:
- fasting glucose
- HbA1c
- insulin
- measured insulin resistance.[8]
This is an important finding because it helps define the limits of the evidence.
The strong and repeatable finding for trehalose is the lower acute glucose and insulin response compared with free glucose.
Current research does not establish trehalose as a treatment for diabetes or as a substitute for medical management.
Does Trehalose Cause a Blood-Sugar Spike?
Trehalose raises blood glucose because it is ultimately digested into glucose.[1,2]
What differs is the speed and magnitude of that response.
Compared with the same amount of free glucose, human studies have repeatedly reported:
- a lower early glucose peak
- lower total post-meal glucose exposure
- a smaller insulin peak
- lower total insulin exposure.[2–5]
A useful way to understand trehalose is therefore:
a glucose-providing carbohydrate with a more gradual post-meal profile than free glucose.
Why Does This Matter for Food Formulation?
Sugar performs many functions beyond sweetness.
Depending on the food, it can contribute to:
- texture
- bulk
- solids
- moisture management
- freezing behaviour
- structure
- browning
- shelf quality.
Simply replacing sugar with a high-intensity sweetener does not reproduce these physical functions.
TREHA® offers another option.
It is a genuine functional sugar ingredient with:
- mild sweetness
- useful physical properties
- approximately 4 kcal per gram
- a metabolic profile that differs substantially from free glucose.
This combination is relevant to product developers looking to control sweetness without abandoning the functional benefits of a real carbohydrate ingredient.
For practical applications, see Trehalose for Food →.
Trehalose and Sports Nutrition
The slower appearance of glucose following trehalose ingestion has also attracted interest in sports nutrition.
Researchers have investigated trehalose:
- before endurance exercise
- during prolonged cycling
- in distance runners
- in mixed-carbohydrate drinks
- during extended high-intensity exercise.
Trehalose has been shown to function as an exercise carbohydrate while producing a different glucose and insulin profile from rapidly absorbed glucose.
For the detailed exercise evidence, see Trehalose for Exercise & Endurance: What Does the Research Show? →.
Is Trehalose a “Low-GI Sugar”?
Trehalose is frequently described online as a low-GI sugar.
There is legitimate research behind that description, particularly the controlled human trial in which trehalose produced 38% of the two-hour glucose response to the same quantity of glucose.[2]
However, that experiment did not use the standard 50 g carbohydrate protocol traditionally associated with formal glycaemic-index testing.
For that reason, a more precise description is:
Human studies consistently show that trehalose produces a lower and more gradual blood-glucose and insulin response than an equivalent quantity of free glucose.[2–5]
And where a numerical comparison is useful:
In one controlled crossover study, 25 g of trehalose produced 38% of the two-hour glucose response and 36% of the insulin response produced by 25 g of glucose.[2]
These are directly measured human results rather than an assumed universal GI value.
What Does the Research Tell Us?
The current human evidence supports several clear conclusions.
Trehalose Is a Source of Glucose
It is digested into two glucose molecules before absorption.[1,2]
It Is Digested Differently from Free Glucose
The enzyme trehalase must first hydrolyse the trehalose molecule.[2]
The Acute Blood-Glucose Response Is Lower than with Glucose
This has been demonstrated across several controlled human studies and different participant groups.[2–5]
The Insulin Response Is Also Lower
Human trials consistently report a smaller insulin response following trehalose compared with free glucose.[2–5]
The Frequently Quoted “38” Has an Experimental Basis
A crossover trial found that 25 g trehalose produced 38% of the two-hour glucose response to 25 g glucose.[2]
Longer-Term Research Is Developing
Regular-consumption studies have produced some interesting findings, but they are less consistent and should be distinguished from the much stronger acute glucose-response evidence.[6–8]
A Note on Health Claims in Great Britain
This guide summarises published scientific research into how the human body responds to trehalose.
It should not be interpreted as claiming that TREHA® prevents, treats or manages diabetes or any other medical condition.
In Great Britain, health claims made in commercial food communications must be authorised under the Great Britain Nutrition and Health Claims Register.[9]
The most useful role of this guide is therefore to explain the research and the distinctive metabolic behaviour of trehalose without turning those findings into medical or therapeutic claims.
The Bigger Picture
Trehalose occupies an unusual position among sugars.
It is:
- a genuine carbohydrate
- a source of glucose
- about 40% as sweet as sucrose
- a functional food ingredient
- digested more gradually than free glucose
- associated with substantially lower acute glucose and insulin responses than glucose in controlled human studies.[2–5]
That combination explains why trehalose attracts interest across food formulation, carbohydrate research and endurance nutrition.
Perhaps the most important conclusion is also the simplest:
Not all glucose-containing carbohydrates reach the bloodstream in the same way.
Trehalose is a particularly clear example.
Further Reading
Trehalose vs Sugar: What's the Difference? →
Trehalose for Exercise & Endurance: What Does the Research Show? →
References & Further Reading
[1] Food Standards Agency. “Trehalose: Authorised Novel Food NOVEL-140.” Great Britain authorisation defining trehalose as a disaccharide of two glucose units and requiring foods containing it to carry the statement “Trehalose is a source of glucose.”
Food Standards Agency: Trehalose authorisation →
[2] Chiyo Yoshizane, Akiko Mizote, Mika Yamada, et al. 2017. “Glycemic, Insulinemic and Incretin Responses after Oral Trehalose Ingestion in Healthy Subjects.” Nutrition Journal 16: 9. Twenty healthy adults consumed 25 g trehalose and 25 g glucose in a crossover study. DOI: 10.1186/s12937-017-0233-x.
[3] Kevin C. Maki, Mitchell Kanter, Tia M. Rains, Serena P. Hess, and Jeffrey Geohas. 2009. “Acute Effects of Low Insulinemic Sweeteners on Postprandial Insulin and Glucose Concentrations in Obese Men.” International Journal of Food Sciences and Nutrition 60, supplement 3: 48–55. DOI: 10.1080/09637480802646923.
[4] Judith G. P. van Can, T. Herman IJzerman, Luc J. C. van Loon, Fred Brouns, and Ellen E. Blaak. 2009. “Reduced Glycaemic and Insulinaemic Responses Following Trehalose Ingestion: Implications for Postprandial Substrate Use.” British Journal of Nutrition 102, no. 10: 1395–1399. DOI: 10.1017/S000711450999050X.
[5] Judith G. P. van Can, Luc J. C. van Loon, Fred Brouns, and Ellen E. Blaak. 2012. “Reduced Glycaemic and Insulinaemic Responses Following Trehalose and Isomaltulose Ingestion: Implications for Postprandial Substrate Use in Impaired Glucose-Tolerant Subjects.” British Journal of Nutrition 108, no. 7: 1210–1217. DOI: 10.1017/S0007114511006714.
[6] Akiko Mizote, Mika Yamada, Chiyo Yoshizane, et al. 2016. “Daily Intake of Trehalose Is Effective in the Prevention of Lifestyle-Related Diseases in Individuals with Risk Factors for Metabolic Syndrome.” Journal of Nutritional Science and Vitaminology 62, no. 6: 380–387. DOI: 10.3177/jnsv.62.380.
[7] Chiyo Yoshizane, Akiko Mizote, Chikako Arai, et al. 2020. “Daily Consumption of One Teaspoon of Trehalose Can Help Maintain Glucose Homeostasis: A Double-Blind, Randomized Controlled Trial Conducted in Healthy Volunteers.” Nutrition Journal 19: 68. DOI: 10.1186/s12937-020-00586-0.
[8] Somayyeh Hashemian, Mehrnaz Shojaei, Shabnam Radbakhsh, et al. 2023. “The Effects of Oral Trehalose on Glycaemia, Inflammation, and Quality of Life in Patients with Type 2 Diabetes: A Pilot Randomized Controlled Trial.” Archives of Medical Science 19, no. 6: 1693–1700. DOI: 10.5114/aoms/159048.
[9] Department of Health and Social Care. “Great Britain Nutrition and Health Claims Register.” Register of nutrition and health claims permitted in commercial communications in England, Scotland and Wales.