Isomaltulose vs sucrose in a 12-week weight loss diet
What it found
In overweight adults on an energy-reduced diet, isomaltulose led to a slightly larger weight loss and fat loss than sucrose, but the difference between groups was not statistically significant.
The isomaltulose group also ate less and burned more fat after breakfast.
What they found
Studies in people
Weight loss
Both groups lost weight over the 12 weeks. The isomaltulose group lost on average 3.2 kg and the sucrose group 2.1 kg, but the difference between groups was not statistically significant.
Fat mass
The isomaltulose group had a significant reduction in fat mass of 1.9%, while the sucrose group's reduction of 0.9% was not significant. The difference between groups was not statistically significant.
Energy intake
The overall decrease in energy intake was significantly greater in the isomaltulose group (544 kcal per day) compared to the sucrose group (283 kcal per day).
Fat oxidation
After a breakfast containing isomaltulose, the rise in respiratory quotient was significantly lower than after sucrose, suggesting more fat oxidation. Fat oxidation was higher after isomaltulose at all study visits, though not always significantly.
Waist circumference
Waist circumference decreased in both groups, but the changes were not significant within either group and did not differ between groups.
Tolerance
No serious adverse events were reported. One participant reported an upset stomach on days she ate cheese sandwiches for lunch, but the study diet and carbohydrates were overall well tolerated.
What the authors conclude
“Our data hence suggest that ISO, a slow-release and low-glycemic sugar alternative, might be a useful tool to promote weight loss and thus improve metabolic risk factors.”
Also in their conclusions
- They conclude that participants on a low-glycemic diet with isomaltulose showed a higher weight loss and fat mass loss compared to those on sucrose.
- They suggest that isomaltulose, a slow-release and low-glycemic sugar alternative, might be a useful tool to promote weight loss and improve metabolic risk factors.
- They advise that additional beneficial effects of isomaltulose on the maintenance of weight loss merit further examinations.
How it was done
Low-glycemic diets have been shown to improve metabolic status and increase fat oxidation compared to high-glycemic diets. The authors wanted to see if replacing sucrose with isomaltulose, a low-glycemic sugar, would support weight loss and fat loss in overweight and obese people.
Sixty-four healthy overweight or obese adults were assigned to consume either 40 g per day of isomaltulose or sucrose as part of an energy-reduced diet for 12 weeks. Fifty participants completed the study, and body weight, body composition, energy intake, and energy metabolism were measured at the start and after 4, 8, and 12 weeks.
What it can’t tell you
- The study lasted only 12 weeks, so it cannot show what happens over a longer period.
- The difference in weight loss between the two groups was not statistically significant, so the study cannot prove that isomaltulose causes more weight loss than sucrose.
- The study did not measure insulin or other hormones, so it cannot explain exactly how isomaltulose might affect metabolism.
Who paid
- Funding
- Funded by BENEO GmbH / Südzucker Group (from the PubMed record).
- Conflicts
- S.T. and L.S. are employees of BENEO GmbH/Südzucker Group.
- Authors work at
- Oxford Brookes University, UK; BENEO-Institute, Germany; Technology and Research (A*STAR) and National University Health System, Singapore
The paper
- Title
- Changes in Weight and Substrate Oxidation in Overweight Adults Following Isomaltulose Intake During a 12-Week Weight Loss Intervention: A Randomized, Double-Blind, Controlled Trial
- Type
- Randomised controlled trial
- Evidence
- Studies in people
- Summarised from
- Full text
- Licence
- CC BY. Words in quotation marks are the authors’; the rest is our summary.
- Cite
- Lightowler H, Schweitzer L, Theis S, Henry CJ (2019). Changes in Weight and Substrate Oxidation in Overweight Adults Following Isomaltulose Intake During a 12-Week Weight Loss Intervention: A Randomized, Double-Blind, Controlled Trial. Nutrients. doi:10.3390/nu11102367Free full textPubMed 31590285DOI
Summary written 30 Sep 2026. Check it against the paper before it changes what you eat. How we summarise papers · Report an error