Maltitol and glucose effects on blood sugar and phosphate
What it found
In a small study of black and white men, maltitol raised blood sugar in black men but not white men, and lowered blood phosphate in white men but not black men.
Glucose did the opposite pattern.
What they found
Studies in people
Blood sugar after glucose
After glucose, blood sugar rose significantly in white men (from 4.8 to 6.2 mmol/l) but not in black men (from 4.7 to 5.3 mmol/l).
Blood phosphate after glucose
After glucose, blood phosphate fell significantly in black men (from 1.16 to 1.01 mmol/l) but not in white men (from 1.24 to 1.15 mmol/l).
Blood sugar after maltitol
After maltitol, blood sugar rose significantly in black men (from 4.7 to 5.2 mmol/l) but not in white men (from 4.6 to 5.9 mmol/l).
Blood phosphate after maltitol
After maltitol, blood phosphate fell significantly in white men (from 1.24 to 1.18 mmol/l) but not in black men (from 1.17 to 1.06 mmol/l).
What the authors conclude
- They suggest that enzymes which regulate glycolysis may be less active in black men than in white men, or that the expression of renal transcellular glucose transporters may be relatively inhibited in black men.
- They say that effects on blood phosphate depend on the type of carbohydrate and race, so no general rule can be made linking these variables.
- They note that inter-race differences in how carbohydrates are handled might affect kidney stone risk factors in these groups.
How it was done
The authors wanted to understand how glucose and maltitol affect blood sugar and phosphate levels, because these changes might influence the risk of kidney stones. They also noted that carbohydrate metabolism can differ between race groups.
Eight healthy black men and eight healthy white men followed a set diet for 7 days, then a strictly controlled diet on day 8. After an overnight fast, each man drank either glucose or maltitol, and blood was taken before and 30 minutes after. The drinks were swapped after a 1-week break.
What it can’t tell you
- We summarised it from the abstract only.
- This was a small study with only eight men per group, so the results may not apply to all people.
- The study only looked at one time point after drinking the solutions, so it cannot show longer-term effects.
- The study cannot prove that these changes in blood sugar and phosphate actually cause kidney stones.
Who paid
- Authors work at
- University of Cape Town, South Africa
The paper
- Title
- Glycaemia and phosphatemia after oral glucose and maltitol ingestion in subjects from two different race groups: preliminary evidence of inter-race differences in metabolism and possible implications for urinary stone disease
- Type
- Study
- Evidence
- Studies in people
- Summarised from
- Abstract only
- Cite
- Theka T, Rodgers A (2017). Glycaemia and phosphatemia after oral glucose and maltitol ingestion in subjects from two different race groups: preliminary evidence of inter-race differences in metabolism and possible implications for urinary stone disease. International urology and nephrology. doi:10.1007/s11255-017-1623-xPubMed 28526969DOI
Summary written 26 Sep 2026. Check it against the paper before it changes what you eat. How we summarise papers · Report an error