In brief

  • Isomaltulose (also known by the trade name Palatinose™) is a slowly digested, low glycaemic index carbohydrate that provides a steady and sustained supply of energy in the bloodstream
  • Isomaltulose ingestion had been associated with greater fat burning potential after meals and after exercise, and may reduce appetite
  • Isomaltulose is the ideal carbohydrate source in formulations such as carbohydrate loaders, recovery shakes and meal replacements for individuals looking to promote or maintain a lean physique and reduce percentage body fat


Isomaltulose is a low glycaemic index (GI) ´designer´ carbohydrate with a range of properties that make it attractive as a functional ingredient in nutrition formulations. Isomaltulose is present naturally in honey and sugar cane, whereas the commercial form (i.e. Palatinose) is produced by a process of bacterial fermentation of common table sugar (aka sucrose). Although similar in composition to table sugar, i.e. a disaccharide (meaning ‘two sugar’) molecule combining fructose and glucose, the bonds that link the two sugar molecules of isomaltulose are, in effect, harder to break down during digestion, and consequently make this an attractive carbohydrate source for several reasons.

Isomaltulose is not broken down by salivary enzymes, but instead is slowly, but fully, digested and absorbed from the stomach and small intestine. This slower rate of digestion and absorption means the release of the sugar molecules into the bloodstream also occurs at a slower rate compared to conventional sugars. Hence, the glycaemic index (a measure of the speed and size of a change in blood sugar levels) of isomaltulose is very low i.e. 32 compared to other simple sugars (e.g. glucose is ~100, table sugar is ~60) [1]. Conventional carbohydrate ingredients used in nutrition supplements and meal replacement shakes such as processed starch, glucose/dextrose, glucose syrups, maltodextrin and sucrose are more rapidly digested carbohydrates that induce a relatively high glycaemic response.

This is important because the release of insulin is proportional to the relative increase in blood sugar levels. While insulin is an essential hormone for regulating blood sugar balance and can stimulate muscle growth (protein synthesis), insulin is also a powerful hormone in promoting the storage of fat. In short, low glycaemic (glucose release) and low insulinaemic (insulin release) foods are generally considered more favourable choices because by preventing rapid fluctuations in blood sugar (sugar highs, hunger pangs and sugar crashes) they (i) promote higher rates of fat burning and fat loss, (ii) provide a feeling of fullness for longer, and (iii) contribute a steady, sustained release of energy that is positive for physical and mental performance. Finally, isomaltulose also resists fermentation and digestion by microbes, which means that it can be used in powder formulations without the need for artificial preservatives.

What does the research say about isomaltulose?

Several studies have reported smaller increases (generally, about 50% less) in blood sugar and insulin levels in the first 60 min after consuming meals or drinks where traditional sugar sources have been replaced with isomaltulose[2, 3, 4, 5, 6]. This coincides with higher rates of fat oxidation (a measure of the body’s ability to burn fat) in the aftermath of eating the meal[2, 3, 5, 6] . This has been observed in both normal weight and perhaps, more importantly, overweight individuals. Interestingly, in one study, the increase in a hunger hormone known as ghrelin was lower 2 hours after a meal in which sugars were substituted with isomaltulose [3]. The favourable responses in blood sugar mean that isomaltulose has been suggested as a better carbohydrate source for diabetics [4].

The overall effect of these metabolic responses is likely to favour fat burning instead of fat storage after a meal and over time result in less fat being accumulated. In fact, in studies that have taken place over a longer timeframe, rats fed with diets where the major sugar was isomaltulose had less body fat and less metabolic abnormalities compared to rats with a traditional sugar diet[7]. Longer term studies in humans are only preliminary but have also shown a reduction in blood triglycerides (a type of fat that is a risk factor for cardiovascular disease) by 10-15% after 12 weeks when part of the sugar content of the diet was replaced with isomaltulose[8] .

Finally, during exercise, drinking isomaltulose showed similar results to these studies at rest, including a lower rise in blood sugar and insulin compared to a sucrose drink, and approximately 15% higher rates of fat oxidation during exercise. Levels of fat in the blood were also higher during exercise suggesting that more fat was being mobilised (i.e. broken down) from the various fat stores around the body [9].

What does this mean in practice?

Carbohydrate loading: Carbohydrate loading is recommended for endurance and team sport athletes in the lead-up to competition and matches. This involves consuming large amounts of carbohydrate (often greater than 500 g per day), which can be difficult using solid food alone. A similar problem may occur for athletes who undertake prodigious amounts of training e.g. greater than 2 hours every day, but need to keep their carbohydrate intake high to support recovery and performance. Using liquid fuel sources is the best alternative in this scenario. A drink containing predominantly isomaltulose, such as FUEL LOAD®, is highly recommended, and will provide a high dose of carbohydrate, but avoid the sugar highs and crashes associated with other carbohydrate loading drinks by providing a steady supply of carbohydrate throughout your day.

Physique and recovery: For those athletes looking to maintain or develop a lean physique with low percentage body fat, a dilemma often arises between the fear of gaining excessive fat mass when consuming simple sugars versus the need to take onboard large amounts of carbohydrate to support training and performance. To address this issue, ROS Nutrition have developed a range of recovery and mass gain products i.e. ALPHA MASS®, METAMUSCLE® and RECOVERACE STRENGTH®, which contain isomaltulose as the major carbohydrate source. Athletes consuming these products can expect the beneficial effects of isomaltulose substitution on fat burning described above, but still receive the benefits of carbohydrate consumption for supporting gains from training.

Meal replacement and fat loss: Isomaltulose has beneficial effects on fat burning and appetite hormones in overweight individuals, and this makes it an ideal source of carbohydrate in meal replacement and fat loss formulations. ROS Nutrition products such as MEAL SHOT®, FEMME MEAL® and FEMME SHAPE® take advantage of this science by including isomaltulose as the principal source of CHO in these low carbohydrate, high protein, nutrient-rich formulations.

Isomaltulose as a sugar: As a two sugar molecule, isomaltulose is listed as a sugar form of carbohydrate on food ingredient labels. As a general rule, when consuming carbohydrate sources, a high proportion of starch (i.e. complex) as opposed to sugar (i.e. simple) carbohydrate is advised e.g. a sweet potato is a healthier form of carbohydrate compared to a soft drink. However, as explained above, isomaltulose behaves very differently to traditional sugars, and can be considered a ‘healthy’ form of sugar. In fact, in Japan and China, isomaltulose is used as a sugar substitute for diabetics and in enteral feeding preparations.

Find isomaltulose at ROS Nutrition


FUEL LOAD® is a carbohydrate loading drink that can be used specifically for carbohydrate loading regimens or as form of slow digesting, low GI carbohydrate to supplement your daily diet – whatever way you choose, you will be fuelled for performance. Additional ingredients include B vitamins and beta-alanine designed to compliment a high carbohydrate intake with ingredients that support energy metabolism and intense performance.


ALPHA MASS® and METAMUSCLE® are ROS Nutrition’s proprietary formulations designed to support gains in body mass with gym training. These products contain large doses of a variety of ingredients known to promote greater gains and improve recovery from training including protein, BCAAs, creatine, HMB, and glutamine to name but a few. We use isomaltulose as the main source of carbohydrate in these all-in-one formulations to ensure that the majority of gains will be in the form of lean muscle rather than fat. The inclusion of isomaltulose in these formulations may also be useful for people who consume them as a pre-workout shake by providing sustained energy levels and greater fat burning during training.


RECOVERACE STRENGTH® is a carbohydrate-protein recovery drink designed to be more attuned to the recovery from resistance training and gaining lean muscle mass as opposed to endurance training and recovery of muscle carbohydrate stores of its sister product RECOVERACE ENDURANCE®. RECOVERACE STRENGTH® features an optimal blend of carbohydrate, protein and amino acids to maximise rates of muscle protein synthesis (essential for muscle growth) in order to enhance recovery and promote gains from training. With isomaltulose as the major source of carbohydrate, we provide a recovery product that provides a source of carbohydrate for recovery, but of a low GI that in turn allows for greater rates of fat burning during recovery than other recovery products. This is of particular interest for those individuals looking to maintain low percentage body fat, or in weight category sports where optimising body composition is a major goal.


MEAL SHOT®, FEMME MEAL® and FEMME SHAPE® are a series of meal replacement formulations designed to aid fat loss, improvements in muscle tone and body composition for all shapes and sizes. Each product provides a blend of nutrients that promote fat burning with a combination of high quality protein and active ingredients, and suppress appetite by produce feelings of fullness for longer. These can be used to support training goals or simply as a high quality source of nutrients for people on the go. While each is generally low in carbohydrate, the source of this carbohydrate is predominantly isomaltulose, thereby providing a great tasting low GI meal replacement with sustained energy levels and fat burning potential after consumption.

Further reading

  • Atkinson FS, Foster-Powell K, Brand-Miller JC (2008) International tables of glycemic index and glycemic load values: 2008. Diabetes Care 31(12):2281-3
  • Arai H, Mizuno A, Sakuma M, Fukaya M, Matsuo K, Muto K, Sasaki H, Matsuura M, Okumura H, Yamamoto H, Taketani Y, Doi T, Takeda E (2007) Effects of a palatinose-based liquid diet (Inslow) on glycemic control and the second-meal effect in healthy men. Metabolism 56(1):115-21
  • van Can JG, Ijzerman TH, van Loon LJ, Brouns F, Blaak EE (2009) Reduced glycaemic and insulinaemic responses following isomaltulose ingestion: implications for postprandial substrate use. Br J Nutr 102(10):1408-13
  • Holub I, Gostner A, Theis S, Nosek L, Kudlich T, Melcher R, Scheppach W (2010) Novel findings on the metabolic effects of the low glycaemic carbohydrate isomaltulose (Palatinose). Br J Nutr 103(12):1730-7
  • van Can JG, van Loon LJ, Brouns F, Blaak EE (2012) Reduced glycaemic and insulinaemic responses following trehalose and isomaltulose ingestion: implications for postprandial substrate use in impaired glucose-tolerant subjects. Br J Nutr (in press)
  • König D, Theis S, Kozianowski G, Berg A (2012) Postprandial substrate use in overweight subjects with the metabolic syndrome after isomaltulose (Palatinose) ingestion. Nutrition 28(6):651-6
  • Sato K, Arai H, Mizuno A, Fukaya M, Sato T, Koganei M, Sasaki H, Yamamoto H, Taketani Y, Doi T, Takeda E (2007) Dietary palatinose and oleic acid ameliorate disorders of glucose and lipid metabolism in Zucker fatty rats. J Nutr 137(8):1908-15
  • Brunner S, Holub I, Theis S, Gostner A, Melcher R, Wolf P, Amann-Gassner U, Scheppach W, Hauner H (2012) Metabolic effects of replacing sucrose by isomaltulose in subjects with Type 2 diabetes: A randomized double-blind trial. Diabetes Care 35(6):1249-51
  • Achten J, Jentjens RL, Brouns F, Jeukendrup AE (2007) Exogenous oxidation of isomaltulose is lower than that of sucrose during exercise in men. J Nutr 137(5):1143-8