Drinking a ketone supplement before meals improved blood sugar and blood lipid levels in people with type 2 diabetes. Digest
People with type 2 diabetes often experience sharp rises in blood sugar and blood fats after eating, changes that increase the risk of heart disease over time. Researchers investigated whether drinking a ketone supplement before a meal could improve these metabolic swings.
You just missed this in your inbox
Every other week our Premium Members received this exact study plus Rhonda's practical commentary and 8+ other hand-picked papers.
The research consisted of two carefully controlled crossover studies in adult patients with type 2 diabetes who were treated with lifestyle changes or metformin. In the first study, 14 participants drank one of three beverages 30 minutes before a standardized meal: a ketone monoester, a ketone salt, or a placebo. In the second study, 10 participants consumed a placebo or different doses of the ketone monoester at varying times before an oral glucose tolerance test (OGTT), a standard test in which a glucose drink is consumed to measure how the body processes sugar over time.
- Compared with placebo, a single 30 g dose of ketone monoester reduced post-meal blood glucose exposure by 36%, while ketone salts produced a smaller 22% reduction.
- The ketone monoester lowered the peak blood sugar level, whereas ketone salts mainly delayed the rise without reducing the peak.
- Both ketone supplements strengthened the normal post-meal drop in circulating non-esterified fatty acids (fats released from body fat stores) that is typically blunted in patients with type 2 diabetes because their fat tissue does not respond well to insulin. Ketone monoesters reduced their levels by about 51%, and ketone salts by roughly 37%, compared with placebo.
- Only the ketone monoester clearly reduced post-meal triglycerides, lowering overall triglyceride exposure by about 53%.
- Both supplements lowered ghrelin, a hunger-stimulating hormone, and especially ketone salts increased the LEAP-2/ghrelin ratio, a signal associated with fullness and appetite suppression. Reported hunger and later food intake were unchanged.
- During the OGTT, 20 g and 40 g doses of ketone monoester reduced glucose exposure by 29% and 38%, respectively, while 10 g had no clear effect.
- Timing mattered: taking 20 g 30 or 60 minutes before glucose intake reduced glucose exposure by 29% and 25%, respectively, whereas taking it at the same time produced no clear benefit.
- No serious side effects occurred. Digestive symptoms and mild, transient electrolyte changes were more common with ketone salts, and taste was frequently described as unpleasant.
To explore why blood sugar responses improved, a labeled form of glucose was added as a tracer to the test meal to track how glucose entered the bloodstream during digestion. The ketone monoester slowed the entry, suggesting slower movement of food through the gastrointestinal system or slower absorption. Ketone salts did not slow glucose entry, indicating that additional mechanisms may be involved. Across all interventions, glucose production by the liver and glucose uptake by tissues followed similar patterns, suggesting these processes did not drive the improvements.
Overall, the findings suggest that taking a ketone supplement before meals may offer a practical strategy to improve metabolic health in people with type 2 diabetes. Larger and longer studies will be needed to confirm long-term safety, real-world effectiveness, and whether these improvements translate into fewer diabetes-related complications. In this clip, Dr. Dominic D'Agostino shares tactical tips for ketone supplementation.