Mulberry

Food · Fruit · Food, Typed Supps

Mulberries are a sweet-tart berry packed with vitamin C and a natural compound that can help slow sugar spikes after a meal.

Stage by stage

Chewing & Release (Mouth): Chewing ruptures the mulberry's thin skin and juicy flesh, releasing its natural sugars, vitamin C, and anthocyanin pigments into saliva.
Gastric Breakdown (Stomach): In the stomach, acid and enzymes break down the fruit's cell walls, freeing bound vitamin C, iron, and polyphenols for further digestion.
Intestinal Absorption (Small intestine): The small intestine absorbs vitamin C, iron, and fiber, while the compound DNJ in the fruit temporarily blocks the alpha-glucosidase enzyme, slowing the breakdown of starches into absorbable sugar.
Bloodstream Delivery (Bloodstream): Absorbed vitamin C and anthocyanins enter the bloodstream, supporting immune cell function and delivering antioxidant activity to tissues throughout the body.

Timing

Mulberries' blood-sugar-blunting compound (DNJ) works by slowing carbohydrate digestion in the gut, so it's most relevant when eaten alongside — not separately from — a starchy or sugary meal.

Time to effect

Hours: The fiber, sugar, and vitamin C in mulberries are digested and absorbed within a few hours, and any glucose-blunting effect from DNJ is limited to the single meal it's eaten with.

Allergens

None of the fourteen major allergens. Derived from what this food is, not from a product label.

Eating patterns

Fits: Vegan, Vegetarian, Pescatarian, Halal, Kosher, Keto, Gluten-free. Depends on the product: Low-FODMAP.

Satiety

The satiety index is measured on 240 kcal servings. At 33 kcal per 100 g that is 723 g of this, which is not a serving anyone eats — so the index has nothing to say about it.

Environmental footprint

1.1 kg CO2e and 199 litres of freshwater per kg, matched to "Other fruit" in Poore & Nemecek (2018), Science 360.

Cost band

Cheap — roughly £3 per kg, as a band midpoint rather than a price.

Key nutrients

Vitamin C
Iron
Anthocyanins
Dietary Fiber
1-Deoxynojirimycin (DNJ)

Nutrition per 100g

Calories: 33.2
Protein: 2.2g
Carbohydrate: 4.3g
of which sugars: 4.3g
Fat: 0.2g
of which saturated: 0g
Fibre: 2.2g
Sodium: 6mg

Food vs. supplement

Whole mulberries provide vitamin C, iron, fiber, and a modest amount of DNJ together, while mulberry leaf extract supplements isolate and concentrate DNJ specifically to blunt post-meal blood sugar spikes, a use case fresh fruit cannot reliably replicate.

Kitchen tip

Mulberries are highly perishable and don't ripen further once picked, so choose plump, deep-colored berries and refrigerate or freeze them within a day or two of purchase.

Common myth

"Mulberries (or mulberry tea) are a fat-burning superfood that melts pounds away." In reality: Clinical trials show mulberry extract's DNJ compound modestly reduces the glucose and insulin spike after a carbohydrate-containing meal (roughly 20-24% in one trial of a 250 mg standardized extract), but there is no evidence it burns fat or causes weight loss on its own.