Cabbage

Cabbage (Brassica oleracea var. capitata)

Cabbage (in Hebrew “כרוב”) is the least glamorous vegetable in the supermarket, and also one of the best nutritional bargains in it. 100 grams of cabbage — less than the weight of a slice of bread — provide 63% of the daily intake of vitamin K and 41% of vitamin C, in 25 calories and at a price of a few shekels per kilo.

It belongs to the cruciferous family together with cauliflower, broccoli, Brussels sprouts, kale and kohlrabi — all of them, surprisingly, species or subspecies of the same wild plant domesticated thousands of years ago.

And this page also answers a question many people get wrong: when sauerkraut really contains live bacteria, and when it’s just a sour vegetable.

Nutrition facts per 100 grams

White or red? Red cabbage provides almost twice as much vitamin C, plus anthocyanins — the purple pigments that are also antioxidants. White cabbage provides twice as much vitamin K and more folate. Both are good; for variety, eat both.

Sauerkraut — when it contains live bacteria

Sauerkraut and kimchi are made by spontaneous lactic fermentation: lactic acid bacteria that are already present on the cabbage multiply in the salty environment, convert sugars into lactic acid and sour the vegetable. The process produces live bacteria, breaks down some of the gas-causing compounds and increases the availability of some minerals.

And here’s the detail people miss: most sauerkraut sold in shelf-stable jars has been pasteurized after fermentation, so it won’t keep fermenting in the package. Pasteurization kills the bacteria. A jar from the dry shelf = a tasty sour vegetable, zero probiotics.

How to recognize the real thing:

• Sold refrigerated, not on a room-temperature shelf.
• Ingredient list: cabbage, salt, and maybe spices. No vinegar — vinegar indicates quick pickling, not fermentation.
• It often says “unpasteurized” or “live cultures.”
• The lid may be slightly bulging — a sign that fermentation is continuing.

Historically, sauerkraut was the reason sailors stopped getting scurvy on long voyages: lactic acid preserves the vitamin C that in most vegetables would be destroyed in storage.

Benefits

• A large amount of vitamin K: 76 mcg per 100 grams in white cabbage — 63% of daily intake, needed for blood clotting and for directing calcium to bone rather than to blood vessels.
• Vitamin C: 41% in white and 63% in red — more than an orange per 100 grams, at half the calories.
• Glucosinolates: Sulfur compounds from the cruciferous family (in cabbage mainly sinigrin and glucobrassicin), studied in the context of detoxification enzymes and inflammation pathways. The evidence in humans is early.
• Fiber: 2.5 grams per 100 grams with an energy density of just 25 calories.
• Fermentation: In the unpasteurized version — live lactic acid bacteria and fermentation products, along with a reduction in some gas-causing compounds.
• Price and availability: One of the cheapest vegetables per kilo, keeps for weeks in the fridge, and hardly ever spoils. A real practical advantage.
• Anthocyanins in red cabbage — the same family of pigments that gives blueberries and pomegranate their color.

Downsides and considerations

• Gas and bloating. Cabbage contains raffinose and fructans that are not broken down in the small intestine and are fermented in the colon. This is the most common complaint about it. Cooking, fermenting or slicing thinly reduces it; increasing the amount gradually also helps.
• FODMAP. White cabbage is considered low-FODMAP in a serving of about 75 grams, and in larger amounts may trigger symptoms. Red cabbage is tolerated in a similar amount.
• Vitamin K and anticoagulants. 63% of daily intake per 100 grams is a significant amount. People on Coumadin don’t need to avoid cabbage — they need steady, consistent intake, so the drug dose can be calibrated to it. Sharp fluctuations are the problem.
• Goitrogens and the thyroid. As with other cruciferous vegetables — the effect is practical only with a combination of existing iodine deficiency and very large intake of the raw vegetable. Cooking reduces it.
• Sodium in sauerkraut. Sauerkraut reaches 600-800 mg of sodium per 100 grams — almost a third of the daily recommendation. An excellent condiment, not a serving.
• Loss of vitamin C when boiled. Vitamin C is water-soluble and heat-sensitive; prolonged boiling draws much of it into the water.
• Smell during long cooking. Sulfur compounds break down and release mercaptans. Shorter cooking in an uncovered pot reduces this.

Practical use

• Eat some of it raw. A thinly sliced cabbage salad with lemon and olive oil keeps all the vitamin C, and also provides the glucosinolates in their active state.
• Don’t boil it for long. Steam or stir-fry quickly for 4-5 minutes. If you do boil it — keep the water for soup.
• Slice thinly. The thinner the slicing, the softer the cabbage, the better it is digested and the less gas it causes.
• Buy sauerkraut from the refrigerator, with an ingredient list of cabbage and salt only — as detailed above.
• Combine with fat: Vitamin K is fat-soluble; a tablespoon of olive oil or tahini in the cabbage salad is not a garnish but a condition for absorption.
• Red stays red with acid. Anthocyanins change color according to pH — a little lemon or vinegar in the salad or the cooking will keep the purple hue instead of turning bluish-gray.
• Store it whole. A whole head of cabbage keeps in the fridge for 3-4 weeks. After cutting — about a week, in an airtight container.

Summary

Cabbage provides 63% of the daily intake of vitamin K and 41% of vitamin C in 25 calories, at the lowest price per kilo in the produce section, and with a shelf life of weeks. It is one of the simplest justifications in the whole menu. Two things are worth remembering: red and white are not the same — red wins on vitamin C and anthocyanins, white on vitamin K; and sauerkraut from the dry shelf is not a probiotic — only the version sold refrigerated, with an ingredient list of cabbage and salt only and no vinegar, contains live bacteria.