← All supplements
Limited evidencePhysical performance

Isomaltulose (Palatinose)

A slowly digested sugar sold as steady endurance fuel. It reliably produces a flatter glucose curve, but that has not translated into better performance in the trials that measured it.

Where to buy

View on iHerb

Ships to 180+ countries · welcome discount for new customers

Referral link — this site may earn a commission on purchases.

What the science says

  • Flatter glucose and insulin response Moderate evidence

    A double-blind randomised crossover trial before prolonged aerobic exercise confirmed isomaltulose produces lower and more sustained glucose and insulin responses than high-glycemic carbohydrate, with greater fat oxidation.

  • Performance benefit not demonstrated Limited evidence

    In that same randomised crossover trial the metabolic differences did not produce better performance in the exercise bout that followed.

  • Narrow niches with specific evidence Limited evidence

    Small randomised trials have examined isomaltulose before exercise in adults with type 1 diabetes on automated insulin delivery, and inside glycerol-based hyperhydration drinks, with modest and situation-specific effects.

Dosage & safety

Studied dose25–75 g taken 45–60 minutes before endurance exercise in trials. During exercise it is usually blended with faster carbohydrates rather than used alone.
SafetyDigested to glucose and fructose, so it is not calorie-free and is unsuitable in hereditary fructose intolerance. Slow digestion can cause bloating or loose stools at larger doses. It still raises blood glucose, just more gradually.

How to take it

TimingTake it 45 to 60 minutes before endurance exercise, which is the studied protocol.
With food?On its own in fluid, not with a meal.
Worth knowingDo not rely on it during high-intensity work, because its slow digestion means it can sit in the gut and cause bloating when blood flow leaves the stomach.

Interactions

With medications

  • insulin and other glucose-lowering medication

    It still raises blood glucose, just more slowly, which can mistime an insulin dose. plan the dose with your diabetes team rather than treating it as low-glycaemic and free

Well-established interactions only — this is not a complete list. Always tell your doctor and pharmacist what you take.

Frequently asked questions

Does isomaltulose (Palatinose) improve endurance performance?

Isomaltulose (Palatinose) reliably produces a flatter glucose and insulin curve and more fat burning, which is moderate evidence, but in the trial that measured performance this did not translate into a better result. The evidence for an endurance performance benefit from isomaltulose is limited.

How much isomaltulose should I take before exercise?

Trials used 25–75 g of isomaltulose taken 45–60 minutes before endurance exercise, on its own in fluid. During exercise, isomaltulose is usually blended with faster carbohydrates rather than used alone.

Does isomaltulose raise blood sugar?

Yes, isomaltulose is digested to glucose and fructose and still raises blood glucose, just more gradually, and it is not calorie-free. If you take insulin, plan isomaltulose doses with your diabetes team, and avoid it in hereditary fructose intolerance.

Does isomaltulose cause bloating?

Isomaltulose digests slowly, so larger doses can cause bloating or loose stools, especially during high-intensity work when blood flow leaves the gut. Avoid relying on isomaltulose during hard efforts for that reason.

Scientific references

Related in Physical performance