People frequently place foods into "health" or "diet" categories. This study examined whether (1) evaluations of "healthiness/unhealthiness" influence "caloric" estimation accuracy, (2) people evaluate foods for "healthiness/unhealthiness" or "weight gain/loss" differently. and (3) food evaluations differ by gender, diet status, and weight. Also, undergraduate dieters attempting to lose weight on their own were compared to obese weight loss program participants. Undergraduate students (N = 101) rated eight "healthy" and "unhealthy" foods on perceived "healthiness/unhealthiness," "weight loss/gain capacity" and "caloric" content. Open-ended questions inquiring why a food was "healthy/unhealthy" or would "contribute to weight gain/loss" were coded into independent food categories (e.g., high fat). Results indicate that calories were systematically underestimated in healthy/weight loss foods, while they were systematically overestimated in unhealthy/weight gain foods. Dieters were more accurate at estimating "calories" of healthy foods and more attentive to the foods' fat. "calorie". and sugar content than non-dieters. Overweight participants commented more on fat and sugar content than normal weight participants. Undergraduate dieters used fewer categories for evaluating foods than weight loss program participants. Individual difference characteristics, such as diet-status, weight, and gender, influence people's perceptions of foods' healthiness or capacity to influence weight, and in some instances systematically bias their estimates of the caloric content of foods. (C) 2007 Elsevier Ltd. All rights reserved.