Functional foods are typically fortified with nutrients that would not be there otherwise.  Calcium-fortified orange juice qualifies is a functional food because calcium is not found naturally in this food, but calcium-rich yogurt doesn’t. Functional foods is one of the hottest trends in the food industry, but it is as controversial as it is profitable. A wealth of evidence supports adding calcium to soymilk to prevent bone loss, plant sterols to orange juice to lower heart disease risk , or folic acid to grains to prevent birth defects. But what about adding ginkgo to a drink that contains only water and 14 teaspoons of sugar (SoBe Green Tea 20 fl ounces) or vitamin A to a drink where the first two ingredients are water and sugar? Also, while it is relatively easy to keep track of how much of a nutrient or herb you are consuming when it is taken as a supplement, it is much more difficult to monitor your intake when it comes from a variety of processed foods. For example, we know so little about optimal doses, interactions, or long-term consequences of most phytochemicals and herbs that to begin adding them haphazardly into foods could produce any number of potential toxic effects.

Bottom Line: This is a trend that is both thumbs up and thumbs down. Thumbs up if a nutrient is added in safe amounts to an already healthy food, such as calcium or vitamin D added to OJ. But it is a definite thumbs down if a junk food tries to pass itself off as healthy by adding one or more nutrients or herbs.