Effects of (non)deceptive placebos on reported sleep quality and food cue reactivity

Abstract

SummaryA lack of sleep can increase appetite, particularly for high‐calorie food. The current study tested the effects of an open‐label placebo for improving sleep quality and reducing food cue reactivity. In open‐label placebo interventions, placebo recipients are informed that they are receiving a placebo without a pharmacologically active substance. Participants (n = 150) were randomly allocated to one of three groups that received either an open‐label placebo to improve sleep quality, a deceptive placebo (“melatonin”), or no placebo. The placebo was administered daily before bedtime for 1 week. Sleep quality and reactivity to high‐calorie food cues (appetite, visual attention to food images) were assessed. The deceptive placebo (but not the open‐label placebo) reduced reported sleep‐onset latency. The open‐label placebo decreased perceived sleep efficiency. The placebo interventions did not change food cue reactivity. This study demonstrated that open‐label placebos do not present an alternative to deceptive placebos for improving sleep quality. The undesirable open‐label placebo effects found warrant further exploration.