1-deoxynojirimycin (DNJ) is the main active compound in white mulberry leaves (Morus alba L.). This natural “iminosugar” temporarily inhibits intestinal alpha-glucosidase enzymes, which normally break complex carbohydrates down into simple glucose. By slowing this process, DNJ supports a more gradual release of sugar into the bloodstream after meals. This is a targeted, physiological action limited to the post-meal window, with no effect on fasting blood sugar.

Browse our full range in store.

White mulberry has been used for centuries in traditional Asian herbal practice for its role in metabolism. Its leaves contain DNJ alongside flavonoids, polyphenols and amino acids. The flavonoids and polyphenols in the extract work alongside DNJ to support overall carbohydrate metabolism, an area that has been explored in several human clinical trials.

Not all white mulberry extracts are equal — DNJ concentration makes the real difference. With a guaranteed 5% DNJ standardisation, each capsule of this Dynveo extract provides 18mg of DNJ, a dose in line with the amounts studied in human clinical research. This standardisation is achieved through a water-and-ethanol extraction process with no chemical solvents, with HPLC analysis on every batch checking DNJ content and screening for pesticides, residual solvents and heavy metals.

This extract is aimed primarily at people looking to naturally support their post-meal carbohydrate metabolism, particularly after carb-rich meals, as well as athletes managing their energy and older adults, whose insulin sensitivity naturally declines with age. Take 1 capsule at the start of each main meal (3 capsules a day) with a glass of water — timing matters, as DNJ needs to be present in the gut when the meal’s carbohydrates arrive.

Food supplement. Not a substitute for a varied, balanced diet and a healthy lifestyle. Do not exceed the recommended daily dose. If you are following medical guidance related to blood sugar, seek medical advice before supplementing to avoid interactions.

How does the DNJ in white mulberry work?

DNJ temporarily inhibits intestinal alpha-glucosidase enzymes, which break complex carbohydrates into glucose. This slows sugar absorption after meals. The effect is transient and limited to the post-meal period, with no impact on fasting blood sugar.

Are there side effects with white mulberry?

At the recommended dose, DNJ-standardised white mulberry extract is considered safe. Some users may notice mild digestive effects in the first days, related to enzymatic modulation, which typically resolve quickly. We suggest starting with a substantial meal if you have a sensitive digestion.

Why take white mulberry at the start of a meal?

DNJ needs to be present in the gut before the meal’s carbohydrates arrive to inhibit alpha-glucosidases effectively. Taking it with a glass of water at the start of the meal gets DNJ to the site of action at the right time — taking it away from a meal significantly reduces its effectiveness.

Herba Barona is an independent specialist supplement shop in the heart of Paris — established in 2006. What you order is genuinely on our shelves: we ship from our own stock, with no dropshipping and no long waits.

Visit us at 10 rue Théophile Roussel, Paris 12 — or use Click & Collect and pick up your order in-store. We also deliver across France and Europe. Friendly, expert advice in English from our team.

Where is the shop?

Herba Barona is at 10 rue Théophile Roussel, 75012 Paris — a two-minute walk from Ledru-Rollin (line 8), close to Bastille. Open Tuesday to Saturday, 9:30 am–6:30 pm.

Can I order online or collect in store?

Yes. We ship across France and Europe under the same conditions as our French store, or choose Click & Collect to pick up your order for free at our Paris shop.