What’s common to eggplant (aka brinjal, aubergine), dark grapes, beetroot, plums, figs, cranberries, some cabbages? Their natural purple color. The purple color comes from anthocyanins which are naturally occuring chemicals in the plant. These are superlative antioxidants and help to fight cancer. There’s more research going on with anthocyanins and their health benefits. The purple foods are also good sources of vitamin C, and / or contain antioxidants like resveratrol, quercetin, etc.
Make sure you eat at least one purple food every week.