Supplements · Metabolic & Cardiometabolic
Does mulberry leaf blunt the blood-sugar spike after a meal?
The claim, precisely: mulberry leaf (1-deoxynojirimycin) decreases postprandial glucose
Yes, a compound in it slows starch digestion like a drug, but whether it survives baking into bread is untested.
Evidence ladder
How far up the ladder this claim has climbed. A high consensus on a low rung means "consistent so far," not "proven in people."
Top evidence so far: Human trials (RCT / n-of-1)
How the studies fall
What the evidence shows
Mulberry-leaf DNJ blunts postprandial glucose/insulin via intestinal alpha-glucosidase inhibition (acarbose-like) at low dose — mechanistically ideal for a starchy bread, but thermal survival through baking is the critical unproven gate.
The evidence (6)
| Source | Grade | Stance | Quality | Finding |
|---|---|---|---|---|
| (mulberry+water-chestnut) 2025 · (RCT crossover) | RCT | supports | moderate | RCT crossover n=31 CGM DNJ tea lowered glucose CV p=.0006 + 1h AUC. Tea not bread - bake-stability unproven |
| (DNJ RCT) 2007 · (RCT) | RCT | supports | moderate | DNJ-enriched 0.8-1.2 g suppressed post-sucrose glucose/insulin |
| (MLAE RCT) 2015 · (RCT) | RCT | supports | moderate | RCT n=36 prediabetic MLAE 5g/d attenuated postprandial glucose/insulin; lower insulin iAUC p=.02 |
| (MLAE RCT) 2015 · (RCT) | RCT | supports | moderate | 5 g/d MLAE lowered postprandial glucose & insulin iAUC in prediabetics |
| (mulberry+water-chestnut) 2025 · (RCT crossover) | RCT | supports | moderate | Mulberry-leaf + water-chestnut suppressed postprandial hyperglycemia (2025 confirmatory RCT) |
| (DNJ RCT) 2007 · (RCT) | RCT | supports | moderate | HUMAN DNJ 0.8-1.2g suppressed postprandial glucose+insulin after sucrose |
Educational only, not medical advice. Grades and scores reflect published evidence weighted by study design and quality; see the methodology.