Table 8_Nutritional habits, inhibitory control, and emotional reactivity to healthy and unhealthy food cues in non-obese female students: insights from heart rate variability.docx

BackgroundResearch shows that the nutritional habits of university students do not follow the national recommendations. While most studies have focused on the increased risk of overweight/obesity, avoiding unhealthy food or maintaining a normal weight does not necessarily result in a regular consumption of healthy essential nutrients.
MethodsThe present study was aimed at investigating the interplay between emotional reactivity and inhibitory control in 42 non-obese female students exposed to healthy (fish/lean meat, fruit/vegetables) and unhealthy (savory and sweet junk food) food pictures, after an average fasting of 7.5 h. Resting heart rate variability (HRV) was assessed as a physiological index of self-regulation, exploring its association with emotional reactivity and inhibitory control, as well as its predictive role in nutritional habits. We measured valence, arousal and craving during a free viewing time task and assessed inhibitory and attentional control through an emotional Go/NoGo task. Hunger, nutritional habits and frequency of physical activity were also collected.
ResultsUnhealthy foods elicited higher pleasantness, arousal and craving than healthy foods, indicating stronger appetitive motivation. Emotional reactivity was predicted by hunger or fasting duration as a function of food type. Higher HRV predicted slower reaction times to Go stimuli for all food types except fruit/vegetables. HRV and physical activity negatively predicted the habitual consumption of sweet junk food and positively predicted that of fruit/vegetables.
ConclusionOur results provide novel insights into the mechanisms underlying dietary self-regulation in non-obese female students, highlighting the significant role of resting HRV and physical activity in promoting healthy dietary choices and limiting junk food intake.

【研究背景】已有研究表明，大学生的营养摄入习惯并未符合国家膳食推荐标准。当前多数相关研究多聚焦于超重/肥胖（overweight/obesity）的患病风险升高，但规避不健康食品或维持正常体重，并不等同于能够规律摄入足量的健康必需营养素。
【研究方法】本研究旨在探究42名非肥胖女大学生在平均空腹7.5小时后，面对健康食品（鱼类/瘦肉、水果/蔬菜）与不健康食品（咸甜类垃圾食品）图片时，情绪反应与抑制控制之间的交互作用。本研究以静息心率变异性（resting heart rate variability, HRV）作为自我调节的生理学指标，分析其与情绪反应、抑制控制的关联，以及其对营养摄入习惯的预测作用。实验中，我们通过自由观看任务采集被试对食物图片的效价、唤醒度与渴求度数据，并借助情绪Go/NoGo任务（emotional Go/NoGo task）评估被试的抑制与注意控制能力。此外，本研究还收集了被试的饥饿状态、营养摄入习惯与体育活动频率数据。
【研究结果】相较于健康食品，不健康食品能够引发更高的愉悦度、唤醒度与渴求度，表明其具有更强的摄食趋近动机。情绪反应受饥饿状态或空腹时长的调控，且该调控效应因食品类型而异。除水果/蔬菜外，较高的HRV水平均会延长被试对各类食品图片的Go刺激反应时。HRV水平与体育活动频率可负向预测被试对甜类垃圾食品的日常摄入量，正向预测其对水果/蔬菜的日常摄入量。
【研究结论】本研究结果为非肥胖女大学生的膳食自我调节机制提供了全新视角，同时凸显了静息HRV与体育活动在促进健康膳食选择、减少垃圾食品摄入方面的重要作用。