Superfood or Not? DEA Makes the Call
*Christine Pitocco, Stony Brook University
Keywords: Superfood, DEA, nutrition, food
Use of the term “superfood” in the popular health literature has grown by a factor of almost 20 over the past 40 years. Yet, there is no operational definition of the term that provides a clear and unequivocal method to determine whether a given food may be classified as a superfood. In this paper, we use a variable returns to scale, mixed orientation Data Envelopment Analysis model to evaluate 164 foods that are listed on at least one of 8 published lists of purported superfoods. We identify seven nutrients that should be present in smaller amounts and treat them as the inputs of the DEA model. Similarly, we identify 28 nutrients that should be present in larger amounts and treat them as the outputs. We find that 145 of the foods (88.4%) are on the efficient frontier. The remaining 19 foods (11.6%) lie below the efficient frontier and cannot be classified as superfoods. Among the surprising non-superfoods are blueberries (on 5 of the 8 lists); quinoa (on 3 lists); and apples, onions, pomegranates, sour cherries (on 2 lists each). Sadly, dark chocolate, which appears on 4 lists, has the lowest efficiency score (77.0%).