Red Cabbage Health Benefits, Anthocyanins and Indicator Fun

Cabbage of any color is a healthy addition to the diet, but red cabbage has an extra benefit compared to its green relative due to the presence of red, purple or blue pigments called anthocyanins. Scientists are discovering that anthocyanins in plants may have many health benefits, including helping to prevent cancer, improving heart and blood vessel health, improving brain function, vision and diabetes, relieving inflammation and fighting infections.

Anthocyanins are present in other vegetables (such as purple potatoes, purple corn, beets and red onions), fruits (such as strawberries, blueberries, red and purple grapes and blood oranges) and grains (such as red and purple rice). Hundreds of different anthocyanins have been discovered. Scientists still have a lot to learn about these chemicals and their effects inside the body, and health benefits attributed to the anthocyanins in one plant may not be provided by the anthocyanins in another plant. However, the discoveries made so far have convinced nutritionists that we should all be eating a wide variety of anthocyanin-containing foods for their potential benefits.

Anthocyanins and Red Cabbage Color

Red cabbages may actually be purple or even bluish rather than red, since anthocyanins change color as the pH changes. The pH scale is a number scale ranging from 0 to 14 and indicates how acidic or basic a substance is. An acidic substance has a pH of less than 7. A neutral substance, which is neither acidic nor basic, has a pH of 7. A basic or alkaline substance has a pH of greater than 7. The pH of the soil controls the color of the red cabbages growing in the soil.

Anthocyanins inside red cabbage are red in an acidic solution, purple in a neutral solution and blue in a basic solution. A little vinegar added to the container in which red cabbage is cooking will keep the cabbage red, since vinegar contains acetic acid.

Red Cabbage Anthocyanins and Health

Thirty six different anthocyanins have been found in red cabbage. Lab experiments have shown several useful effects of these anthocyanins. In test tube reactions they are antioxidants. One experiment showed that red cabbage anthocyanins protected nerve cells from damage in lab dishes and may have a useful role to play in the treatment of Alzheimer’s disease. This is a hopeful discovery, but it needs to be confirmed by other scientists. In addition it’s not known if anthocyanins have the same effect inside the brain. Clinical trials in humans are required. In a lab cell culture, red cabbage anthocyanins prevented colon cancer cells from multiplying. This is also good news, but once again the results need to be confirmed, and scientists don’t yet know if eating red cabbage anthocyanins will cause the same effect in our bodies. Red cabbage juice has been found to reduce inflammation, possibly due to protein components in the juice as well as the anthocyanins.

While it’s true that tests in humans are needed to prove the beneficial effects of red cabbage anthocyanins on health disorders, it’s a nutritious food even without its other potential health benefits, so it’s a great idea to include it in the diet.

Raw red cabbage is rich in nutrients. It's an excellent source of vitamin C and of vitamin A in the form of beta carotene, which our bodies convert into true vitamin A. Red cabbage is also a great source of vitamin K and a good source of vitamin B6, riboflavin, folate, thiamin and certain minerals, including manganese, potassium, calcium, magnesium and iron. Red cabbage contains fiber and is almost fat free, and contains a small quantity of natural sugars. Since the water-soluble vitamins leach into the water when cabbage is boiled, red cabbage should be eaten raw, or the boiling water should be drunk. Steaming is a gentler way to cook cabbage. A small amount of a healthy oil should be eaten with the cabbage to enhance the absorption of the fat-soluble vitamins.

Cabbage belongs to the family of flowering plants known as the Brassicaceae, which is sometimes known as the family Cruciferae. The members of this family have molecules called glucosinolates in their cells, as well as an enzyme called myrosinase. When the cabbage is cut or chewed, the myrosinase reacts with the glucosinolates to produce potential cancer fighting molecules called indoles and isothiocyanates. Red cabbage produces an isothiocyanate called sulforaphane. Sulforaphane has been found to inhibit the growth of cancer cells in lab dishes and slow the growth of tumors in mice. Sulforaphane is present in green cabbage too, but in a smaller amount.

Surveys of large numbers of people have found that those who regularly eat vegetables from the Brassicaceae family, such as any type of cabbage, cauliflower, broccoli, kale and Brussels sprouts, have a lower risk of developing cancer than those who don't eat many of these vegetables.

Drinking cabbage juice has been found to help treat peptic ulcers. Cabbage has also been found to lower blood cholesterol level, especially when it's steamed.

Red cabbage juice is a popular liquid in school acid-base experiments due to its anthocyanins that change color at different pH's. The juice is obtained by boiling red cabbage in a small amount of water for five to ten minutes and then removing the cabbage leaves once they’ve released anthocyanin pigments into the water. Red cabbage juice is an indicator. In chemistry, an indicator is a chemical that has one color when it’s added to an acidic substance and a different color when it’s added to a basic substance. The indicator can therefore be used to test a substance to “indicate” if it’s acidic or basic.

The starting color of the red cabbage juice depends on the pH of the water used to extract the anthocyanins. Red cabbage juice is pink or red in an acidic solution, reddish purple in a neutral solution and blue-green or yellow green in a basic solution. It’s fun to use a red cabbage indicator in home science experiments. Safe acids for children to test are lemon juice and vinegar. Distilled water, which you can buy in drug stores and supermarkets, is neutral. An antacid tablet added to water will give a safe base to test. Baking soda powder is also a basic material.

Researchers and nutritionists agree that it’s important that we eat cabbage (including red cabbage) and its relatives frequently, in both raw and lightly cooked forms. They are nutritious foods, and there is a lot of evidence that suggests that these vegetables have additional health benefits, including helping to prevent cancer.