Laboratory of Biological Psychology, Faculty of Psychology and Educational Sciences, KU Leuven, Belgium; Radboud University Medical Centre, Donders Institute for Brain, Cognition and Behaviour, Cognitive Neuroscience Department.
Physiol Behav. 2024 Dec 1;287:114707. doi: 10.1016/j.physbeh.2024.114707. Epub 2024 Sep 28.
People use various behaviors to cope with stressful events. These behaviors are mostly adaptive, as they allow a successful release of stress without impacting other aspects of life: How nice is it to have a break with a few spoons of that favorite ice cream during a hectic working day? However, when excessive consumption of high-sugar/salt ultra-processed food becomes the gateway to find relief from stress, eating loses this adaptive function and may escalate to binge eating, lead to obesity, and other medical conditions linked to overweight. Several etiological models attempt to explain stress-induced eating and excessive overeating behaviors characterizing these clinical conditions. The popular Emotional Eating Theory proposes that stress-related (over-)eating, a major predictor of obesity and diagnosed binge eating disorders, develops based on negative reinforcement learning since food consumption regulates the negative affective state associated with stressful circumstances. Differently, the prominent Incentive Sensitization Theory explains overeating, binge eating disorders (including bulimia), and obesity in terms of excessive amplification of reward 'wanting', which is thought to emerge from overexposure to obesogenic (food)cues. The several studies oriented by these theories have paved the way to better understand stress-related (over-)eating and its clinical excesses. However, a deep mechanistic understanding of how and why stress-induced (over-)eating can escalate till clinical forms of overeating remain elusive. A well-funded connection of the mechanisms proposed by the Emotional Eating Theory and the Incentive Sensitization Theory might address this etiological open question. To avoid erroneous arguments, it is however essential to first address the internal theoretical and methodological shortcomings of each theory and connected studies. These shortcomings stem from conceptual fallacies and poorly implemented designs, which might partially explain the 'high variability and low replicability' problem of empirical findings. Next, the formulation of a new integrative model could provide fresh insight into the deep learning and biological mechanisms of this escalation. A successful formalization of this model could then create the much-needed impact in clinical and preventive research since excessive overeating is a behavior hard to change once established. In this opinion paper, I propose to apply recent insights we gathered on the role of relief from the field of safety learning to stress (over-)eating. I will present a new relief-based model that, as a starting point, has the potential to connect the Emotional Eating Theory with the Incentive Sensitization Theory, setting the base for more integrative science.
人们采用各种行为来应对压力事件。这些行为大多是适应性的，因为它们能够成功地释放压力，而不会影响生活的其他方面：在忙碌的工作日中，享用几勺最爱的冰淇淋来放松一下，多么惬意啊！然而，当过度食用高糖/盐的超加工食品成为缓解压力的途径时，进食就失去了这种适应性功能，可能会发展成暴食，导致肥胖和其他与超重相关的健康问题。几种病因学模型试图解释压力诱导的进食和过度暴食行为，这些行为是这些临床病症的特征。流行的情绪性进食理论提出，与压力相关的（过度）进食是肥胖和诊断为暴食障碍的主要预测因素，它是基于负强化学习发展起来的，因为食物摄入可以调节与压力环境相关的负面情绪状态。相反，突出的激励敏感化理论则根据过度放大的奖励“渴望”来解释暴食、暴食障碍（包括贪食症）和肥胖，认为这是由于过度暴露于肥胖相关（食物）线索所致。这些理论指导的多项研究为更好地理解与压力相关的（过度）进食及其临床过度进食铺平了道路。然而，对于压力诱导的（过度）进食如何以及为何会升级为临床形式的过度进食，我们仍缺乏深入的机制理解。情绪性进食理论和激励敏感化理论所提出的机制的深入研究可能会解决这个病因学上的开放性问题。为了避免错误的论点，首先必须解决每个理论及其相关研究中的内在理论和方法学缺陷。这些缺陷源于概念上的错误和设计不当，这可能部分解释了实证研究结果的“高度变异性和低可重复性”问题。其次，新的整合模型的提出可以为这种升级的深度学习和生物学机制提供新的见解。如果这个模型能够成功地形式化，那么它将为临床和预防研究带来急需的影响，因为一旦过度进食行为形成，就很难改变。在这篇观点文章中，我建议将我们在安全学习领域中获得的关于缓解作用的最新见解应用于压力（过度）进食。我将提出一个新的基于缓解的模型，作为一个起点，它有可能将情绪性进食理论与激励敏感化理论联系起来，为更具综合性的科学奠定基础。
