The researchers showed more than 100 study participants nutrition information for a regular Oreo cookie and for one that was made with organic flour and sugar. The nutritional label clearly showed a serving size (two cookies) of 160 calories for both Oreos. Nevertheless, 38 percent of the participants thought that the organic cookie had fewer calories than competing brands, whereas only 12 percent did so without the organic claim.Part of this makes me want to just "face-palm", but it is also understandable: people don't always think through the implications of new information. It might just go into a mental map of "organic is good for me, therefore if I eat organic foods, then I will be more healthy." The first part of this may well be true (although the bulk of evidence supporting the idea that organic food is physiologically better than 'conventional' food is not in), there are more ways for organic foods to be "good" for a body than in calorie counts.
Calorie counts are calorie counts. At some level they are interchangeable. Therefore, if one is counting calories on a non-organic food, its organic counterpart has basically the same number of calories. True, calories from fat have different physiological impacts than calories from protein. True, too, the physiological pathways of different simple sugars are different, but still... at a basic level calories are calories, and at this level, the mistake that the participants make is analogous to the one in which people say that a pound of feathers is lighter than a pound of bricks.