Simon Hedlin has written Calorie Overestimation Bias and Fast Food Products: The Effects of Calorie Labels on Perceived Healthiness and Intent to Purchase. Here's the abstract:
In 2014, the United States Food and Drug Administration announced that chain restaurants with 20 or more locations would be required to put calorie labels on the menu. The merits of the policy depend in large part on three empirical issues: 1) if calorie labels help correct calorie under- or overestimation biases; 2) if the labels lead to changes in consumer behavior, which may improve physical health; and 3) if they have an impact on psychological health. This paper presents data from an online experiment (N = 1,323) in which participants were randomly presented with pictures of food and drink items from major fast-food companies either with or without calorie labels.
The following findings are reported. First, there was calorie overestimation bias among participants, and the respondents thought, on average, that products contained more calories than was actually the case. Second, calorie labels both made participants perceive the products as healthier, and made them more likely to intend to purchase said items. Third, calorie labels did not have any discernible effects either on the expected utility from consuming the products, or on the participants’ experienced well-being.
Thus, while calorie labels did not appear to have any negative effects on psychological health, they did seem to correct a calorie overestimation bias, which may inadvertently improve the perceived healthiness of foods and beverages high in calories, and could also potentially lead consumers to buy more, rather than fewer, such products.