Mannoheptulose blocks a liver enzyme called glucokinase, which slows the liver's handling of incoming glucose.
See the scientific wording
Mannoheptulose inhibits the liver enzyme glucokinase, thereby slowing hepatic processing of incoming glucose; population, dosage, duration, and effect size are not reported.
Mixed evidence
Observational1 of 2 parts have evidence behind them.
Mixed evidence
1 of 2 parts have evidence behind them.
Parts of this claim
Mannoheptulose inhibits the liver enzyme glucokinase.
Supported1 studyInhibition of glucokinase slows hepatic processing of incoming glucose.
Not testedNo studies
Evidence is judged against each part on its own, so a study that tests one part never counts as a verdict on the whole claim.
What the research says
1 study reviewedSupporting (1)
Cross-Sectional StudyIn vitro1998
This study shows that mannoheptulose blocks the first step of glucose processing in liver samples, which fits the claim. It supports the idea, though it does not give exact numbers.
Contradicting (0)
No contradicting studies found yet
That doesn't mean it's settled — it just means no study has tested the opposite.
Quality-weighted scoring: we follow the GRADE framework — each study is rated High, Moderate, Low, or Very Low based on study design, methodology rigor, and risk of bias. A single high-quality RCT can outweigh several weaker observational studies.
Scores reflect study quality, not just count.
Mannoheptulose is a sugar-like molecule. It gets into liver cells. There, it plugs a protein tool called glucokinase. Glucokinase normally attaches a phosphate tag to glucose. That tag is the first step in the liver handling glucose. When mannoheptulose plugs glucokinase, glucose does not get its tag. The liver then handles incoming glucose more slowly.
Score breakdown, mechanism chain, raw evidence, ideal studies needed & 1 supporting study
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Mannoheptulose blocks a liver enzyme called glucokinase, which slows the liver's handling of incoming glucose.
Mechanism
1 studyMannoheptulose is a sugar-like molecule that gets into liver cells and blocks a protein called glucokinase. Glucokinase normally puts a phosphate tag on glucose, which is the first step the liver uses to process glucose. When glucokinase is blocked, glucose does not get its tag, so the liver handles incoming glucose more slowly.
Mannoheptulose is a sugar-like molecule. It gets into liver cells. There, it plugs a protein tool called glucokinase. Glucokinase normally attaches a phosphate tag to glucose. That tag is the first step in the liver handling glucose. When mannoheptulose plugs glucokinase, glucose does not get its tag. The liver then handles incoming glucose more slowly.
Mannoheptulose enters hepatocytes and reaches the cytosol, where glucokinase is located.
Mannoheptulose binds to hepatic glucokinase and hexokinase, inhibiting their catalytic activity with mixed non-competitive and competitive kinetics.
This inhibition blocks the transfer of a phosphate group from ATP to D-glucose, preventing the formation of glucose-6-phosphate.
Reduced glucose-6-phosphate availability decreases glycolytic flux and downstream glucose oxidation in the liver.
As a result, the liver processes incoming glucose more slowly.
Evidence from Studies
Last searched 14h ago
Supporting (1)
Community contributions welcome
This study shows that mannoheptulose blocks the first step of glucose processing in liver samples, which fits the claim. It supports the idea, though it does not give exact numbers.
Contradicting (0)
Community contributions welcome
Score Breakdown
No multi-axis breakdown available yet. The overall Pro / Against score above is the best signal.
- No clinical evidence is available; the score reflects mechanistic plausibility only.
What Would Prove This
Per GRADE and EBM methodology, here is what ideal scientific evidence would look like to definitively prove or disprove this claim, ordered from strongest to weakest.
Systematic Review of Mannoheptulose Effects on Hepatic Glucokinase Activity and Glucose Processing
Systematic search and meta-analysis of controlled in vitro, animal, and human studies measuring hepatic glucokinase activity and hepatic glucose uptake/processing after mannoheptulose exposure, with standardized doses, durations, and comparators.
Randomized Controlled Trial of Mannoheptulose vs Placebo on Hepatic Glucokinase Activity and Glucose Processing in Humans
Double-blind randomized placebo-controlled trial in healthy adults or relevant patients; oral or intravenous mannoheptulose at defined dose for defined duration; measure hepatic glucokinase activity and hepatic glucose processing via tracer kinetics or glucose clamp; comparator placebo.
Prospective Cohort of Mannoheptulose Exposure and Hepatic Glucose Processing Markers
Prospective cohort with measured mannoheptulose intake or exposure and repeated measures of hepatic glucose processing and glucokinase proxies; adjust for confounders; duration months to years.
Isolated Hepatocyte and Purified Glucokinase Assay for Mannoheptulose Inhibition
In vitro enzyme kinetics with purified hepatic glucokinase and mannoheptulose at multiple concentrations; isolated primary hepatocytes or liver cell lines exposed to mannoheptulose with glucose; measure glucokinase activity, glucose phosphorylation, and downstream glucose processing; comparator vehicle.