Perceived healthiness of food is generally regarded as a positive attribute in food choices, as it positively impacts consumers' preferences. The current research demonstrates that in contexts where there is a time delay between a food's production and its consumption (referred to as "about-to-expire" food), strong perceptions of a food's healthiness can be detrimental. This is because consumers hold a lay theory that healthy food expires more quickly. In eight studies (N = 3,552), the authors find that merely portraying food as healthy increases the perception that it expires quickly and that this effect attenuates when consumers hold the lay theory weakly or have a high level of knowledge about food expiration. Importantly, this lay theory leads consumers to avoid consuming healthy (vs. nonhealthy) about-to-expire food, resulting in increased disposal intentions and decreased preferences. In designing sales promotions for about-to-expire food, managers should consider the healthiness of food products, as consumers prefer different types of sales promotions and require different magnitudes of price discounts for healthy (vs. nonhealthy) about-to-expire food. Finally, adding an expiration date label that provides unambiguous guidance (i.e., "consume by") can effectively mitigate the detrimental effect of perceived healthiness on the consumption for about-to-expire food.