What's the real cost of cheap food?

Do you know where your dinner came from? Most of us want to make sustainable and healthy dining decisions, but busy lives and tight budgets mean imported and processed food often wins out in the quest for cheap and quick meals. Such choices, however, can have environmental, social and economic costs that don’t appear on our grocery bills. Once you consider carbon emissions from transportation and health issues relating to poor eating habits, some of the cheaper options start  looking like less of a good deal. So is the answer to buy local? Or spend more time and money on our food? Can we afford to eat well?