Scallions (Green Onions)

Food · Vegetable · Food, Typed Supps

A few tablespoons of chopped scallions can give you more vitamin K than you'd expect from a simple garnish.

Stage by stage

Chewing & Release (Mouth): Chopping or chewing scallions ruptures their cells, activating enzymes that release organosulfur flavor compounds along with vitamin K, vitamin C, and fiber.
Stomach Breakdown (Stomach): Stomach acid breaks down the plant tissue, freeing fat-soluble vitamin K and carotenoids along with water-soluble vitamin C for absorption downstream.
Intestinal Absorption (Small Intestine): The small intestine absorbs vitamin K together with dietary fat into micelles, while vitamin C, folate, and potassium pass directly into the bloodstream and prebiotic fructans continue on to the colon.
Liver Activation (Liver): The liver uses absorbed vitamin K to activate clotting factors essential for normal blood coagulation, while a portion supports bone- and vessel-protein carboxylation elsewhere in the body.

Timing

Vitamin K is fat-soluble, so eating scallions with some dietary fat, such as in a stir-fry or vinaigrette, improves its absorption compared with eating them completely fat-free.

Time to effect

Days to weeks: Vitamin K helps activate clotting factors in the liver within a few days of adequate intake, while measurable changes in bone-turnover markers from consistent intake typically take several weeks to appear in clinical studies.

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.

In season

August to March in the northern hemisphere, February to September in the southern.

Satiety

The satiety index is measured on 240 kcal servings. At 30 kcal per 100 g that is 789 g of this, which is not a serving anyone eats — so the index has nothing to say about it.

Environmental footprint

0.5 kg CO2e and 14 litres of freshwater per kg, matched to "Onions & leeks" in Poore & Nemecek (2018), Science 360.

Cost band

Cheap — roughly £1.4 per kg, as a band midpoint rather than a price.

Key nutrients

Vitamin K
Vitamin C
Organosulfur compounds
Fructans (prebiotic fiber)

Nutrition per 100g

Calories: 30.4
Protein: 1.7g
Carbohydrate: 4.6g
of which sugars: 4.5g
Fat: 0.2g
of which saturated: 0g
Fibre: 1.9g
Sodium: 13mg

Food vs. supplement

A 100 g portion of scallion provides about 207 mcg of vitamin K (roughly 172% DV) alongside fiber, prebiotics, and organosulfur compounds that an isolated vitamin K supplement doesn't supply, though typical garnish-sized servings deliver much less than the full 100 g value.

Kitchen tip

Use the whole stalk, including the deep-green tops, for the most vitamin K and vitamin C. Because scallions are notably rich in vitamin K, people on warfarin or other vitamin K antagonist medications should eat them in consistent amounts rather than sharply increasing or cutting intake from week to week.

Common myth

The green tops of scallions are just a garnish with little nutritional value compared to the white bulb. In reality: Nutrient data show the chlorophyll-rich green tops actually contain more vitamin K and vitamin C than the white base, so discarding them means throwing away a meaningful share of the plant's nutrition.