Ingestion of an exogenous ketone monoester improves the glycemic response during oral glucose tolerance test in individuals with impaired glucose tolerance: A cross-over randomized trial.
Level 2 - randomized trial
Individual randomized crossover trial
PubMed 33010116 · doi:10.1111/jdi.13423
What was done
Nine Japanese adults aged 48–62 years (4 men, 5 women) with impaired glucose tolerance underwent a 180-minute 75-g oral glucose tolerance test (OGTT) after an overnight fast on two separate days in a randomized crossover design: once with exogenous ketone monoester (KM) ingestion and once without. Researchers measured and compared the area under the curve (AUC) for D-beta-hydroxybutyrate, glucose, insulin, C-peptide, glucagon, and free fatty acids.
What was found
Ketone monoester ingestion significantly raised D-beta-hydroxybutyrate AUC (KM: 5995.3 ± 1257.1 mmol/L·h vs control: 116.1 ± 33.9 mmol/L·h, P < 0.0001) and significantly lowered glucose AUC (KM: 406.6 ± 70.6 mg/dL·h vs control: 483.2 ± 74.3 mg/dL·h, P < 0.0001). This was accompanied by a higher insulin AUC during the first 90 minutes of the test, while 0–90 min C-peptide AUC remained unchanged. Overall 180-minute AUCs for insulin, C-peptide, glucagon, and free fatty acids did not differ significantly between conditions.
Why it matters
This study demonstrates that acute exogenous ketone monoester ingestion can lower postprandial glucose excursions in individuals with impaired glucose tolerance, possibly mediated by an increase in early-phase circulating insulin.
Limits
The sample size is extremely small (n = 9) and restricted to Japanese adults aged 48–62, limiting generalizability. The study only examined acute single-dose effects during a laboratory OGTT, so long-term efficacy, safety, and real-world meal responses were not evaluated.
Cited by
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