Diet foods: do they lead to healthier diets?

Today's Food Navigator reports: "Obesity rocketing despite record diet food spending." The headline is for Europe, but describes the U.S. as well. The headline betrays what may prove to be a critical, but erroneous assumption: that people who eat "diet food" have healthier diets, or lower-calorie diets. That linkage has yet to be tested. For years dietitians have lectured on the fact that there are no "healthy" or "unhealthy" foods, only "healthy" or "unhealthy" diets. But "diet foods" sell, so until we have convincing medical evidence, the public goes on buying them, thinking that they're buying better health. As Peter, Paul and Mary sang in "Where Have All the Flowers Gone?": "When will they ever learn?