Sang Ye is the dried leaf of the white mulberry tree (Morus alba), harvested after the first frost in China and used in Traditional Chinese Medicine for over 2,000 years. In TCM it is considered to cool and clear the lungs, calm wind-heat, and brighten the eyes — but today it is equally valued for its measurable effect on blood sugar. Modern research has confirmed that the leaf contains a unique compound called 1-deoxynojirimycin (DNJ) that directly slows the digestion of carbohydrates.

The key active compound DNJ works by blocking alpha-glucosidase, the enzyme in your gut that breaks down carbohydrates into sugar — so less sugar enters your bloodstream after a meal. Beyond blood sugar, mulberry leaf's polyphenols (quercetin, rutin, chlorogenic acid) act as antioxidants and mild anti-inflammatories that support cardiovascular and metabolic health. It may also gently lower LDL cholesterol by influencing how the liver processes fats.

Tea is the most traditional form and is widely consumed in Japan and China. Standardized capsule or tablet extracts (often 1-5% DNJ) are preferred for blood sugar management since you know the active dose. Powder can be blended into smoothies. For blood sugar purposes, standardized extracts produce more reliable and measurable results than plain tea alone.

• Blood sugar spikes after meals
• Type 2 diabetes (blood sugar support)
• High cholesterol
• Dry cough and sore throat
• Inflammation
• Metabolic syndrome
• High blood pressure (mild support)
• Antioxidant protection
• Weight management support

• Progression from prediabetes to type 2 diabetes (blood sugar normalization over time)
• Cardiovascular risk reduction via LDL lowering and antioxidant protection

• Mulberry fruit (fresh or dried) — The fruit of the same Morus alba tree contains some of the same antioxidant polyphenols (anthocyanins, rutin, quercetin) — a flavorful way to get related compounds, though DNJ concentrations are lower in fruit than leaf.
• Mulberry leaf tea — Widely available in Japan and China as a functional beverage; delivers DNJ and polyphenols in a traditional, low-dose daily format — the most authentic food-adjacent form of Sang Ye.

• Mild digestive discomfort or loose stools (especially at higher doses, from the enzyme-blocking effect)
• Bloating or gas
• Low blood sugar (hypoglycemia) if combined with diabetes medications
• Allergic reactions — rare, but possible in people with known mulberry pollen allergy
• Diarrhea at very high doses

• Recommended daily: For blood sugar support: 1,000–3,000 mg of standardized extract (often standardized to 1–5% DNJ) per day, divided before main meals. Traditional tea: 3–9 g of dried leaf steeped in hot water, 1–2 times daily.
• Best time of day: Take capsule or extract 15–30 minutes before your largest carbohydrate-containing meal of the day for maximum blood sugar benefit. Tea can be enjoyed any time.
• With or without food: Take with or just before food — this is essential for the blood sugar mechanism. Taking on an empty stomach away from meals reduces the carb-blocking effect.
• Time to effect: Noticeable post-meal blood sugar reduction: within 1–2 weeks. Meaningful changes in fasting glucose and HbA1c: 4–12 weeks of consistent use.
• How long to take it: Safe for long-term daily use in traditional practice. Clinical trials have typically run 4–12 weeks. No established need for cycling. Reassess with a healthcare provider every 3–6 months if using for blood sugar management alongside medications.