Evidence-based nutrition, in plain English — every entry sourced from clinical research.

Spinach and kale are the two leafy greens everyone reaches for when a recipe calls for “something green and healthy” — and while both are genuine nutritional powerhouses, they don’t overlap as much as their reputations suggest.

Spinach vs Kale — nutrition per 100 g
NutrientSpinachKale
Calories23 kcal35 kcal
Protein2.86 g2.92 g ✓
Total Carbohydrate3.63 g4.42 g
Dietary Fiber2.2 g4.1 g ✓
Total Sugars0.42 g ✓0.99 g
Total Fat0.39 g1.49 g
Saturated Fat0.06 g ✓0.18 g
Sodium79 mg53 mg ✓

Notable compounds in each

When to choose each

Reach for kale when fibre and vitamin C are the priority — it carries substantially more of both — or when a dish needs a leaf that holds its structure through roasting or massaging into a salad. Reach for spinach for its remarkable vitamin K and folate density, its milder flavour, and how quickly it wilts down into cooked dishes. Both are notable sources of oxalates, worth knowing if you’re prone to calcium-oxalate kidney stones.

Common questions

Which has more iron? Spinach is usually cited as the higher-iron leafy green, though the non-haem iron in either is less readily absorbed than iron from meat — pairing either with a vitamin C source improves absorption.

Is kale harder to digest than spinach? Some people find kale’s tougher fibre harder on the gut, especially raw — massaging it with a little oil or cooking it briefly softens the texture and can make it easier to digest.

Nutrition values are USDA FoodData Central approximations — see our editorial approach for how we source and verify data.