Howatt Brian C, Muñoz Torrecillas María José, Cruz Rambaud Salvador, Takahashi Taiki
Department of Psychological Sciences, Kansas State University, Manhattan, KS, United States.
Department of Economics and Business, Universidad de Almería, Almería, Spain.
Front Public Health. 2019 Jun 26;7:165. doi: 10.3389/fpubh.2019.00165. eCollection 2019.
This paper completes Muñoz Torrecillas et al. (1) results and conclusions investigating the relationship between adherence to healthy dietary habits, specifically the Mediterranean Diet (hereinafter, MD), and impulsivity in intertemporal choices. Impulsivity can be defined as the strong preference for small immediate payoffs over larger delayed payoffs, and in the original study this behavior was captured by the parameter (discount rate of the hyperbolic discount function), calculated using an automated scoring mechanism. Adherence to MD was measured by the KIDMED index and then grouped into three levels: high, medium, and low. While the authors observed that individuals in the high adherence group had the shallowest discounting and individuals in the low adherence group had the steepest discounting, the data were not statistically analyzed in depth. Therefore, the purpose of the present paper is to propose a preliminary quantitative model for this relationship and evaluate its significance. Tests revealed a significant interaction between adherence to MD and magnitude of delayed rewards when predicting discount rates. Specifically, the degree to which impulsivity decreases as adherence to MD increases is strongly influenced by delayed rewards of smaller magnitude. These findings are consistent with the authors' claims that healthy dietary habits may be closely linked with greater self-control when payoffs are small, and thus warrant further examination. The results do not indicate causality though, so future studies could also investigate the directions of this relationship as a means of developing behavioral interventions.
本文完善了穆尼奥斯·托雷西利亚斯等人（1）的研究结果与结论，该研究探讨了坚持健康饮食习惯，特别是地中海饮食（以下简称MD）与跨期选择中的冲动性之间的关系。冲动性可定义为强烈偏好小的即时回报而非大的延迟回报，在原研究中，这种行为通过参数（双曲贴现函数的贴现率）来体现，该参数使用自动评分机制计算得出。通过KIDMED指数衡量对MD的坚持程度，然后将其分为三个水平：高、中、低。虽然作者观察到高坚持组的个体贴现率最浅，低坚持组的个体贴现率最深，但并未对数据进行深入的统计分析。因此，本文的目的是为这种关系提出一个初步的定量模型并评估其显著性。测试显示，在预测贴现率时，坚持MD与延迟奖励的大小之间存在显著的交互作用。具体而言，随着对MD的坚持程度增加，冲动性降低的程度受到较小规模延迟奖励的强烈影响。这些发现与作者的观点一致，即当回报较小时，健康的饮食习惯可能与更强的自我控制密切相关，因此值得进一步研究。不过，结果并未表明因果关系，所以未来的研究也可以调查这种关系的方向，以此作为制定行为干预措施的一种手段。
