Isomalt, gut function and metabolism in healthy volunteers
What it found
In 19 healthy people, eating 30 g of isomalt a day for 4 weeks led to more frequent stools but did not change blood lipids, calcium balance or other metabolic markers compared with sucrose.
The authors say isomalt was well tolerated.
What they found
Studies in people
Blood lipids
Total cholesterol, HDL, LDL, triglycerides and other blood fats were similar with isomalt and sucrose. Apo A-1 was slightly lower with isomalt, but in people with high cholesterol all lipid measures were comparable.
Other metabolic markers
NEFA, leptin, fructosamine, oxidised LDL and remnant-like particles did not differ between the isomalt and sucrose periods.
Calcium and phosphate
Calcium and phosphate levels in urine and stool, and their balance in the body, were not affected by isomalt.
Stool frequency
Stool frequency increased slightly during the isomalt period, but stool consistency and water content stayed the same. Stool weight rose a little, but not significantly.
Gut symptoms
Bloating was mild but more common with isomalt than sucrose. Pain and nausea were rare in both periods.
Other findings
Compliance
Urinary mannitol was higher during the isomalt period, showing that volunteers consumed the test products as instructed.
What the authors conclude
“In conclusion, the present study confirmed that isomalt is well tolerated when consumed for a longer period and does not impair physiological and metabolic parameters.”
Also in their conclusions
- They say isomalt was well tolerated when consumed for a longer period and does not impair physiological and metabolic parameters.
- They suggest that isomalt could be useful in improving bowel function, especially for constipated people.
- They call for further long-term studies to investigate possible benefits for diabetics.
How it was done
The authors wanted to know how regular isomalt consumption affects metabolism and gut function, since little was known about longer-term effects in people.
Nineteen healthy volunteers took part in a randomised, double-blind, cross-over trial with two 4-week periods. They ate a controlled diet plus either 30 g isomalt or 30 g sucrose daily. Blood, urine and stool samples were collected, and gut symptoms and stool habits were recorded.
What it can’t tell you
- The study lasted only 4 weeks, so it cannot show what happens over years of regular isomalt use.
- The volunteers were mostly young and healthy, so the results may not apply to older people or those with constipation or other health conditions.
Who paid
- Authors work at
- University of Würzburg, Germany
The paper
- Title
- Effects of isomalt consumption on gastrointestinal and metabolic parameters in healthy volunteers
- Type
- Randomised controlled trial
- Evidence
- Studies in people
- Summarised from
- Full text
- Cite
- Gostner A, Schäffer V, Theis S, et al (2005). Effects of isomalt consumption on gastrointestinal and metabolic parameters in healthy volunteers. The British journal of nutrition. doi:10.1079/bjn20051510Free full textPubMed 16197583DOI
Summary written 26 Sep 2026. Check it against the paper before it changes what you eat. How we summarise papers · Report an error