Making Herculean efforts to get our five a day of fruit and vegetables ( we manage three on average in the UK ) could also help because they are great for antioxidant vitamins and super-nutrients -- such as vitamin C in citrus fruits , berries and peppers , vitamin E in avocados and the orange beta carotene pigment in carrots and mangos that zaps free radicals formed through being exposed to pollution , sunlight and cigarette smoke .