Last verified: 17 days ago
1-Deoxynojirimycin (DNJ)
Also known as: DNJ, 1-deoxynojirimycin, moranoline, mulberry leaf extract, MLE, Morus alba alkaloid
Evidence under review. — Not yet rated
Natural compound from mulberry leaves that blunts blood sugar spikes after carb-heavy meals.
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What it does
1-Deoxynojirimycin (DNJ) is a natural plant compound found in mulberry leaves that works by blocking an enzyme in your gut called alpha-glucosidase, which breaks down carbohydrates into sugar. By...
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Evidence quality
Evidence base hasn't been formally rated yet. See research below.
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Clinical dose
6-18 mg DNJ daily (with meals) based on clinical studies
What the Science Says
1-Deoxynojirimycin (DNJ) is a natural plant compound found in mulberry leaves that works by blocking an enzyme in your gut called alpha-glucosidase, which breaks down carbohydrates into sugar. By slowing this process, DNJ reduces the sharp rise in blood glucose and insulin that typically follows a carb-heavy meal. Clinical trials show meaningful reductions in postprandial blood glucose at doses of 12 mg or more, with longer-term use (12 weeks) also modestly lowering fasting glucose and HbA1c in people with borderline diabetes.
What It Doesn't Do
Won't replace diabetes medication. Not proven to cure or reverse type 2 diabetes. No solid human evidence it burns fat or helps with weight loss directly. The liver and gut microbiome benefits seen in studies are from animal models only — not proven in people yet. Don't expect it to work if you take it hours before eating.
Evidence-Based Benefits
Reduces the blood sugar spike after carb-heavy meals when taken at 12 mg or more.
Moderate EvidenceEffective at: 12-18 mg DNJ per meal
Supporting studies (click to view on PubMed):
Lowers the glycemic index of common carbohydrates like sucrose, maltose, and maltodextrin.
Weak EvidenceEffective at: No established dose from provided studies
Supporting studies (click to view on PubMed):
Modestly lowers fasting blood glucose and HbA1c in people with borderline diabetes over 12 weeks.
Moderate EvidenceEffective at: 12 mg DNJ three times daily
Supporting studies (click to view on PubMed):
Reduces post-meal insulin secretion alongside blood glucose when taken before carbohydrate intake.
Moderate EvidenceEffective at: 12-18 mg DNJ per meal
Supporting studies (click to view on PubMed):
Absorption & Bioavailability
Moderate — plasma DNJ levels are measurable after oral dosing, but absorption appears higher from whole mulberry fruit extract than from isolated DNJ alone, suggesting other compounds in the plant (like 2-O-alpha-D-galactopyranosyl-DNJ) may act as precursors and enhance uptake.
Red Flags to Watch For
- Gastrointestinal side effects (bloating, flatulence, loose stools) are common — especially at higher doses
- Timing matters: must be taken with or just before a carbohydrate-containing meal to be effective
- DNJ content in commercial mulberry products varies widely; many products contain far less than the effective dose used in studies
- Most liver and gut microbiome benefits are from animal studies only — do not assume these apply to humans
- Not studied in people with type 1 diabetes or those on insulin — potential hypoglycemia risk if combined with blood sugar medications
Products Containing 1-Deoxynojirimycin (DNJ)
See how 1-Deoxynojirimycin (DNJ) is used in these analyzed products:
Frequently Asked Questions
What does 1-Deoxynojirimycin (DNJ) do?
Natural compound from mulberry leaves that blunts blood sugar spikes after carb-heavy meals.
What is the effective dose of 1-Deoxynojirimycin (DNJ)?
6-18 mg DNJ daily (with meals) based on clinical studies
Is 1-Deoxynojirimycin (DNJ) safe?
Gastrointestinal side effects (bloating, flatulence, loose stools) are common — especially at higher doses
What doesn't 1-Deoxynojirimycin (DNJ) do?
Won't replace diabetes medication.
Research Sources
- PubMed
- NIH DSLD
This information is for educational purposes only and is not medical advice. Always consult a healthcare professional before starting any supplement regimen. Last updated: 2026-05-25