Cabbage also has vitaminC which is very important it makes collagen which just happens to be the most abundant protein in your body too you see collagen really gives your skin like structure and also flexibility and vitamin C helps your bones and muscles plus your blood vessels function right,plus vitamin C can help your body to absorb non heme iron which is the type you find in plant foods,plus vitamin C can help to protect your body from free radicals,and research shows us that a diet high in vitamin C show a lower risk of some cancers,now this a fact this study found that for each 100 mg of vitamn C reduced the risk of lung cancer by 7% but then again more studies are really needed here because there is still more inconsistent,but that being said vitamin C does play a very big role in your body,and red cabbage has a good amount of vitamn C like just one cup has about 80-90% of your RDI.