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Kale

Brassica oleracea var. sabellica

Also known as Curly kale, Cavolo nero, Lacinato kale, Borecole

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A loose-leaved cabbage that does not form a head, eaten raw in salads or cooked. Like other Brassica oleracea vegetables it carries glucosinolates, which give it its slightly bitter, sulphurous character.

Heart HealthEye HealthInflammation

Potential health benefits

Best supported: Limited

Ordered by how well the human research supports them — strongest first. A rating describes the state of the evidence, not how impressive the food is. How we rate evidence.

Blood lipid profile

Heart Health
Limited evidence

A small number of trials, mostly of kale juice in men with raised cholesterol, report modest improvements in LDL and HDL. The studies are few, small and largely from one region, so this is early work rather than an established effect.

Limited evidence. Early human work, or mostly lab and animal research.

1 source

Deep research mode adds each paper’s own conclusion and stated limitations.

Macular health

Eye Health
Limited evidence

Kale is among the densest food sources of lutein and zeaxanthin, and higher intake of those carotenoids is associated with denser macular pigment. Trials feeding kale specifically and measuring eye outcomes are scarce.

Limited evidence. Early human work, or mostly lab and animal research.

3 sources

Deep research mode adds each paper’s own conclusion and stated limitations.

Inflammatory markers

Inflammation
Insufficient evidence

Kale is routinely described as anti-inflammatory. Human trials measuring inflammatory markers after eating kale are almost non-existent, so there is nothing dependable to report either way.

Insufficient evidence. Not enough human research to say anything useful yet.

1 source

Deep research mode adds each paper’s own conclusion and stated limitations.

Ask about Kale

Ask about Kale

Answers are written only from the entries on this page — the same nutrients, compounds, claims and citations you can read above. Nothing is added from outside the database, and every answer lists what it was built from.

AI explanations are not switched on for this site, so there is nothing to ask here. Everything above is read straight from the database and does not need them.

Key nutrients

Nutrient content per 100 grams
NutrientAmount% DV
Macronutrients
Calories35 kcal2%
Protein2.92 g6%
Total fat1.49 g2%
Carbohydrate4.42 g2%
Fibre4.1 g15%
Total sugars0.99 g—
Water89.6 g—
Fats
Saturated fat0.178 g1%
Monounsaturated fat0.104 g—
Polyunsaturated fat0.673 g—
Cholesterol0 mg0%
EPA (omega-3)0 g—
DHA (omega-3)0 g—
DPA (omega-3)0 g—
Linoleic acid (omega-6)0.291 g—
Vitamins
Vitamin A241 µg27%
Vitamin C93.4 mg104%
Vitamin D0 µg0%
Vitamin E0.66 mg4%
Vitamin K390 µg325%
Thiamin (B1)0.113 mg9%
Riboflavin (B2)0.347 mg27%
Niacin (B3)1.18 mg7%
Pantothenic acid (B5)0.37 mg7%
Vitamin B60.147 mg9%
Folate62 µg16%
Vitamin B120 µg0%
Choline0.5 mg0%
Minerals
Calcium254 mg20%
Iron1.6 mg9%
Magnesium33 mg8%
Phosphorus55 mg4%
Potassium348 mg7%
Sodium53 mg2%
Zinc0.39 mg4%
Copper0.053 mg6%
Manganese0.92 mg40%
Selenium0.9 µg2%
Other measured compounds
Beta-carotene2873 µg—
Alpha-carotene0 µg—
Lycopene0 µg—
Lutein + zeaxanthin6261 µg—
Caffeine0 mg—
Ash1.54 g—

Nutrient values are per 100 g of the USDA reference entry named on this page and vary with variety, growing conditions, storage and preparation.

Source record: Kale, raw (USDA FoodData Central, FDC ID 168421).

% DV uses the FDA Daily Values for adults and children aged 4 and over. A dash means no Daily Value has been established for that nutrient.

Bioactive compounds

Compounds present in meaningful amounts. Presence is banded rather than quantified, because whole-food levels vary enormously with variety, growing conditions, storage and preparation.

How preparation changes things

Only effects with real support are listed. If a preparation method is missing, it is because nothing dependable is documented — not because it makes no difference.

  • crushedIncreases sulforaphane yield

    Chopping or shredding kale ruptures cells and lets myrosinase act on glucosinolates. Waiting several minutes after chopping before applying heat allows more isothiocyanate to form before the enzyme is destroyed.

  • boiledReduces glucosinolates and myrosinase

    Boiling destroys myrosinase and leaches water-soluble glucosinolates into the cooking water, which cuts isothiocyanate formation sharply compared with lighter cooking.

  • steamedPreserves glucosinolates

    Brief steaming retains far more glucosinolate than boiling because nothing leaches away, and light steaming inactivates a competing plant protein that otherwise diverts the reaction away from sulforaphane.

Things to know

Allergies, interactions and intake concerns. Every food gets this section — a reference where everything is uniformly good is not a reference.

  • Interaction

    Vitamin K and warfarin

    Kale is one of the richest dietary sources of vitamin K1 and directly opposes warfarin. Consistency of intake matters more than avoidance, but a sudden change in how much kale you eat can shift INR appreciably.

  • Worth knowing

    Goitrogens at high raw intake

    Raw cruciferous vegetables release thiocyanates that compete with iodine for uptake into the thyroid. This matters mainly for people who are iodine-deficient; case reports of thyroid problems involve very large daily quantities of raw brassica juice or leaves sustained over months. Cooking largely removes the concern.

  • Too much

    Bloating from raw cruciferous fibre

    The raffinose and insoluble fibre in raw kale are fermented in the colon, which commonly causes wind and bloating when intake increases sharply. Cooking and increasing the amount gradually both help.