Isomaltulose (Palatinose)
A slowly digested sugar sold for steady energy. In the trial that tested it during exercise, cyclists were slower and had more cramps and bloating than on an ordinary glucose-fructose drink.
At a glance
| Our verdict | During exercise it made cyclists slower and caused cramps; no benefit before exercise. |
| Sold for | Sport fuel (claimed) |
| How sure the evidence is | Low to Moderate that it does harm during exercise |
| Cost a month | Not costed in our review; costs more than standard products |
Written for adults in Canada. It explains the evidence; it is not advice for you personally. Last reviewed 20 October 2026.
Supplement Check
Is it right for you?
Using a “slow-release” sport sugar? Your check tells you what to take during your event instead, in grams an hour, and whether your gut or your medicines change the plan. Our Supplement Check looks at:
- Hereditary fructose intolerance
- Diabetes treated with insulin or a sulfonylurea
- A gut that already struggles in long events
- Drug-tested athletes. We ask by example, because few people know the term
- Every medicine you take
Coming soon. The Supplement Check and the Online Health Assessment open once our safety testing is complete.
$59 when it opens, paid once. Adults 18 and over, anywhere in Canada. While the service is new, Dr. French reads every report himself, and your report arrives within 3 working days. More about the Supplement Check
What it is
Isomaltulose (sold as Palatinose) is a sugar made of glucose and fructose joined in a way the gut breaks down slowly. It is sold in some sport drinks and foods as a source of steadier energy. Like other carbohydrate drinks it is a food in Canada, not a natural health product. [1]
How it acts
Because it is digested slowly, it releases glucose and fructose more gradually than ordinary sugar, and in the trial during exercise the body burned more fat. [2] That is the idea behind it. During hard exercise, though, slow digestion means less carbohydrate is available when it is needed, and the undigested sugar left in the gut can cause cramps and bloating.
What it is used for, and what the evidence says
| Use | What the trials found | How sure we are |
|---|---|---|
| During prolonged moderate-to-hard cycling | At 63 g an hour, a 16-km time trial was 1.5 minutes slower than with a fructose-maltodextrin drink (the uncertainty ran about 1.4 minutes either way), with strong cramps and bloating. One crossover trial, 9 cyclists. [2] | Low to moderate (harm) |
| Before exercise | 50 g before cycling gave no benefit over maltodextrin. One crossover trial, 14 young men. [3] | Low |
| For comparison: ordinary carbohydrate during exercise | 61 studies, 82% with a clear benefit over about an hour; [4] glucose plus fructose adds 1 to 9% power at high intakes. [5] | High |
How sure we are: High means further research is very unlikely to change the answer; Moderate, it might; Low, it may well change; Very low, we are very unsure. These follow the GRADE method that guideline panels use.
Benefits
- Performance, taken during exercise: Worse: 1.5 minutes slower over 16 km; Low to Moderate
- Gut comfort during exercise: Worse: cramps and bloating; Low to Moderate
- Performance, taken before exercise: No better than maltodextrin; Low
- Fat burning during exercise: Higher; not a performance benefit; Low
Risks and side effects
- Slower performance and gut cramps and bloating when taken during exercise. [2]
- Fructose: it is half fructose, so the rule for hereditary fructose intolerance applies.
- Blood sugar swings in diabetes treated with insulin if the insulin is not adjusted.
- Cost: more than a standard product, for a worse result.
Interactions with medicines
Our review listed no interactions specific to isomaltulose. Like other sugars it does not change how the liver clears medicines. The cautions that apply to any carbohydrate taken during exercise apply.
| Medicine | What can happen | What to do |
|---|---|---|
| Insulin; gliclazide, glyburide, glimepiride | Carbohydrate during exercise changes blood-sugar control | A doctor-set fuelling plan |
Who should not take it
- Hereditary fructose intolerance: never (it contains fructose).
- Diabetes treated with insulin or a sulfonylurea: a doctor sets the fuelling plan.
- A gut that already struggles in long events.
- Drug-tested athletes. We ask by example, because few people know the term: a national or provincial team, carded athlete or Canada Games; university or college sport (U SPORTS, the CCAA, NCAA); junior hockey (QMJHL, OHL, WHL); a professional or minor-professional league (AHL, ECHL and others); or anyone told they can be tested. “Not sure” counts as yes. Then only a product on the NSF Certified for Sport or Informed Sport register, batch-tested, and the report goes to Dr. French before release.
- Under 18: outside the Supplement Check.
Dose and timing
We do not recommend a dose. For reference, the trials used 63 g an hour during exercise and 50 g before exercise. [2, 3] Use a standard glucose-fructose drink or gel during long efforts, as the game-day plan sets out.
What we know about Canadians
No Canadian data on isomaltulose use in our review. About 27% of Canadians aged 15 and over play a sport regularly, and 14% of those compete. [6]
How sure are we: not graded. No Canadian data on this product; the sport figure is from Statistics Canada's 2016 General Social Survey.
An honest comparison: fuel during long exercise
There is no medicine for this outcome. Cost a month is for 4 long sessions of 2 hours at 60 g an hour.
| Option | Effect | How sure we are | Cost a month (CAD) |
|---|---|---|---|
| Standard batch-certified glucose-fructose drink or gel | Clear benefit against water; [4] 1 to 9% more power than a single sugar at high intakes [5] | Moderate to High | About $80 to $100 |
| Isomaltulose during exercise | 1.5 minutes slower over 16 km, with cramps and bloating [2] | Low to moderate (harm) | Not costed (more than standard) |
| Ordinary food and sugar drinks | Same performance as sport products; slightly more gut symptoms over 2 hours [7] | Low | About $3 to $5 |
| Gut training (practise race feeding for 2 weeks) | Gut symptoms about 60% fewer; performance 4 to 5% better [8] | Low to Moderate | Free |
| None | There is no medicine for this outcome | — | — |
Read honestly: the one trial during exercise found it made performance worse, and the cheaper options all do better.
Why we don't recommend it
We do not sell isomaltulose and our check does not recommend it, before or during exercise.
Already using it? Stop using it during events. Use a standard glucose-fructose drink or gel during long efforts, and practise it in training first.
Taken during exercise, it made cyclists 1.5 minutes slower over 16 km and caused cramps and bloating; [2] taken before exercise, it was no better than maltodextrin. [3] It costs more and can upset your gut when it matters. A standard glucose-fructose drink or gel does better for less. Dr. French ruled that every item we do not sell gets a plain reason in the report; this is it.
Supplement Check
Before you buy it, get it checked
Using a “slow-release” sport sugar? Your check tells you what to take during your event instead, in grams an hour, and whether your gut or your medicines change the plan. Our Supplement Check looks at:
- Hereditary fructose intolerance
- Diabetes treated with insulin or a sulfonylurea
- A gut that already struggles in long events
- Drug-tested athletes. We ask by example, because few people know the term
- Every medicine you take
Coming soon. The Supplement Check and the Online Health Assessment open once our safety testing is complete.
$59 when it opens, paid once. Adults 18 and over, anywhere in Canada. While the service is new, Dr. French reads every report himself, and your report arrives within 3 working days. More about the Supplement Check
Disclosure of financial interest
White Pine Medical earns money from products bought through our Fullscript dispensary. Dr. French's Code of Ethics requires him to tell you this. You do not have to buy anything from us: every product is named by its ingredient and dose so you can buy it at any pharmacy, and the advice is the same wherever you buy it, or if you buy nothing.
References
- Health Canada. Public notice: classification of sports electrolyte products as foods. 23 Apr 2026. https://www.canada.ca/en/health-canada/services/food-nutrition/supplemented-foods/public-notice-classification-sports-electrolyte-products-foods.html
- Oosthuyse T, Carstens M, Millen AM. Ingesting isomaltulose versus fructose-maltodextrin during prolonged moderate-heavy exercise increases fat oxidation but impairs gastrointestinal comfort and cycling performance. Int J Sport Nutr Exerc Metab. 2015;25(5):427-38. PMID 25811946.
- Miyashita M, Hamada Y, Fujihira K, Namura S, Sakazaki M, Miyasaka K, et al. The effects of isomaltulose ingestion on gastric parameters and cycling performance in young men. J Exerc Sci Fit. 2019;17(3):101-7. PMID 31303872.
- Stellingwerff T, Cox GR. Systematic review: carbohydrate supplementation on exercise performance or capacity of varying durations. Appl Physiol Nutr Metab. 2014;39(9):998-1011. PMID 24951297.
- Rowlands DS, Houltham S, Musa-Veloso K, Brown F, Paulionis L, Bailey D. Fructose-glucose composite carbohydrates and endurance performance: critical review and future perspectives. Sports Med. 2015;45(11):1561-76. PMID 26373645.
- Statistics Canada. Sports for fun and fitness (General Social Survey 2016). 11-627-M2019039. https://www150.statcan.gc.ca/n1/pub/11-627-m/11-627-m2019039-eng.htm
- Reynolds KM, Clifford T, Mears SA, James LJ. A food first approach to carbohydrate supplementation in endurance exercise: a systematic review. Int J Sport Nutr Exerc Metab. 2022;32(4):296-310. PMID 35231883.
- Costa RJS, Miall A, Khoo A, Rauch C, Snipe R, Camões-Costa V, et al. Gut-training: the impact of two weeks repetitive gut-challenge during exercise on gastrointestinal status, glucose availability, fuel kinetics, and running performance. Appl Physiol Nutr Metab. 2017;42(5):547-57. PMID 28177715.
Costs marked as estimates are typical Canadian retail or pharmacy prices, before any drug plan. Certainty grades are ours unless the review gave its own.