USDA-derived comparison

Kelp (Seaweed) vs Spinach

Kelp (Seaweed) leads for Magnesium; Spinach answers with Vitamin K, Vitamin C and Vitamin A.

Who each is for: Choose kelp (Seaweed) for magnesium. Choose spinach for vitamin K and vitamin C.

Reviewed 20 July 2026. Generic food data per 100g; brands and preparation vary.

Kelp (Seaweed)

Typical serving: a 10g portion (10g)

18/100

More magnesium
Full Kelp (Seaweed) page

Spinach

Typical serving: 2 cups (60g)

27/100

More vitamin KMore vitamin CMore vitamin AMore vitamin E
Full Spinach page

Side by side, per 100g

The stronger number is highlighted, honestly: higher wins for aim-for nutrients, lower wins for stay-under ones like saturated fat and sodium.

NutrientKelp (Seaweed)Spinach
Calories43 kcal23 kcal
Protein2 g3 g
Carbs10 g4 g
Fat1 g0 g
Fiber1 g2 g
Sat fat0 g0 g
Sodium233 mg79 mg
Potassium89 mg558 mg
Calcium168 mg99 mg
Iron2.9 mg2.7 mg
Magnesium121 mg79 mg
Zinc1.2 mg0.5 mg
Vitamin C3 mg28 mg
Vitamin D0 µg0 µg
Vitamin B120 µg0 µg
Folate180 µg194 µg

Servings differ: a 10g portion of kelp (seaweed) is about 10g, 2 cups of spinach about 60g. Scale accordingly before deciding anything on the 100g basis alone.

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