The Relationship of Hedonic Hunger and Night-Eating Symptoms with Difficulties in Emotion Regulation in Young Adults

Purpose . Tis study aimed to examine the association between hedonic hunger and night-eating syndrome (NES) with difculties in emotion regulation (DER) among young adults. Design and Methods . Tis cross-sectional, descriptive study was conducted on a voluntary basis at a private foundation university, involving a total of 1010 students enrolled in the 2020-2021 academic year. Data were collected through an online application of an information form, which assessed demographic characteristics, the Power of Food Scale (PFS), the Night-Eating Questionnaire (NEQ), and the Difculties in Emotion Regulation Scale-Short Form (DERS-16). Te data were analyzed using IBM SPSS26 ® software. Findings . Women made up 80.4% of the students in the study. Te mean age was 21.58 ± 2.98 years, and the mean body mass index (BMI) was 22.06 ± 3.71 kg/m 2 . Te results indicated that 68.1% of the students reported hedonic hunger and 88.7% had NES. Moreover, DER was found to be more prevalent among women ( p � 0 . 031). In addition, the DERS-16 score increased by 6.5% ( p � 0 . 040) with each increase in age and by 6.8% ( p � 0 . 031) with each increase in BMI. Furthermore, the total PFS score increased by 32.5% ( p < 0 . 001), and the total NEQ score increased by 22.4% ( p < 0 . 001), corresponding to an increase in the total DERS-16 score. Practice Implications . Tese fndings suggest that an increase in the difculties experienced in emotion regulation is associated with higher levels of hedonic hunger and night-eating tendencies among young adults.


Introduction
People have historically sought food to maintain energy homeostasis and ensure survival, thereby preventing hunger [1].However, with the global rise in obesity rates, it has become apparent that food consumption is infuenced not only by energy requirements but also by the pleasurable aspects of eating [2].Tis distinction underscores the existence of two distinct forms of hunger such as homeostatic and hedonic.Homeostatic hunger refers to the physiological control of food intake triggered by a decrease in blood glucose and an increase in free fatty acids.It typically arises after a minimum of 8 hours of nutrient deprivation and is independent of the sensory appeal of food [3].Conversely, hedonic hunger refers to the desire and impulse to eat for pleasure, unrelated to physiological hunger or calorie needs [1].Hedonic hunger is infuenced by various factors, including individual diferences such as age, gender, menstrual cycle, dietary patterns, and responsiveness to food cues.It is also impacted by heightened food cravings, impulsivity, self-perception, and personal experiences.Te sensory characteristics of food, such as taste, color, aroma, texture, and even auditory cues, play a signifcant role in regulating food intake [4].However, excessive consumption of palatable, high-fat, and highsugar foods resulting from hedonic hunger increases the risk of various diseases, including eating disorders, obesity, hypertension, diabetes mellitus, cardiovascular diseases, nonalcoholic fatty liver disease, obstructive sleep apnea, and certain types of cancer [5].
Eating disorders are mental disorders that involve harmful behaviors related to eating, signifcantly impacting individuals' physical and mental well-being [6].Tese disorders are a signifcant public health issue and are prevalent worldwide [7].Night-eating syndrome (NES), categorized as an eating disorder, is characterized by delayed circadian food consumption, binge eating during late-night hours, sleep disturbances, evening mood swings, and other associated symptoms [8].
Emotions hold great importance in human life and are complex systems that have evolved to prepare organisms for environmental stimuli and challenges [9].Various internal and external stimuli trigger emotional responses in daily life, and these emotions manifest through physiological, mental, and behavioral reactions [10].Emotion regulation is the process of amplifying, dampening, or maintaining experienced emotions.Trough emotion regulation, individuals can express and manage their feelings in a controlled manner [11].
When individuals struggle to cope with and regulate their emotions, the concept of difculties in emotion regulation (DER) comes into play.Tis condition is characterized by a lack of emotional awareness, difculty in understanding emotions, being overwhelmed by impulses during negative emotional experiences, and struggling to take goal-oriented actions [12].Research suggests that disordered eating behaviors may either impair emotional awareness or foster avoidance of emotions [13].Tis lack of emotional awareness, acceptance, and coping skills is considered one of the factors perpetuating eating disorders [14,15].Cross-sectional studies in the literature consistently demonstrate relationships between dimensions of emotion dysregulation and eating disorder symptoms and syndromes [16,17].Moreover, defcits in emotion regulation skills are emphasized in the apparent risk [18] and maintenance [19] models of eating disorders.
It is believed that DER plays a role in the development and maintenance of eating disorders.Terefore, understanding the association between hedonic hunger and NES with DER is essential for comprehending the etiology, maintenance, and consequences of eating disorders.However, there is a lack of research on this topic.Tis study aimed to fll this gap by examining the relationship between hedonic hunger and night-eating conditions of university students with DER.

Participants and Procedures
. Tis cross-sectional, descriptive study included a population of 21,000 university students who were registered at a private foundation university during the 2020-2021 academic years.Te sample for the study was obtained using a simple random sampling method.Te sample size was determined using a formula based on the specifed population, and it was calculated that 378 students from the study population would be sufcient for the study, considering a 95% confdence level and a 5% margin of error (z-score: 1.96).Te sample comprised 1010 students who were reached through simple random sampling, participated voluntarily, and completed all data collection tools.Te study received approval from the Ethics Committee (Ethics Committee approval number: 61351342/ 2021-68, dated 29/01/2021) at Uskudar University's Noninterventional Research Ethics Committee.Te participants were informed about the purpose and scope of the study, and their "voluntary consent for participation" was obtained.Tis research was conducted in accordance with the principles outlined in the Helsinki Declaration and adhered to the guidelines of research and publication ethics.
Data collection was conducted via an online survey application of an information form, which questions demographic characteristics (age, gender, anthropometric measurements, exercise status, and so on), the Power of Food Scale (PFS), the Night-Eating Questionnaire (NEQ), and the Difculties in Emotion Regulation Scale-Short Form (DERS-16) via Google Forms between March and May 2021 due to the COVID-19 pandemic.

Power of Food Scale (PFS).
Te PFS was developed by Cappelleri et al. in 2009 as a tool to assess individuals' emotions, thoughts, and desires regarding food and nutrition in environments where appetizing foods are abundant, regardless of physiological needs.Tis scale employs a fvepoint Likert-type format, with response options ranging from 1 (strongly disagree) to 5 (strongly agree).It consists of fve items and includes three subfactors (food available, food present, and food tasted) that measure individuals' responses to the proximity of food.Total scores of 2.5 points or higher on the scale indicate the presence of hedonic hunger, and higher scores on the scale suggest increased motivation to consume appetizing foods in the environment.Mehtap and Melisa et al. [20] conducted a validity and reliability study of the scale in Turkish and calculated Cronbach's alpha coefcient value of 0.85.In the present study, Cronbach's alpha coefcient for the PFS was calculated to be 0.93.

Night-Eating Questionnaire (NEQ).
Te NEQ was developed by Allison et al. in 2008 to assess the severity of night-eating syndrome (NES).It consists of the following four subscales: evening hyperphagia, morning anorexia, mood/sleep, and nocturnal ingestion.Questions 1-9 are answered by all participants, while questions 10-12 are specifc to individuals who wake up at night, and questions 13 and 14 are applicable to those who have night snacks.All items in the NEQ are scored on a fve-point Likert scale.Only the 7th question addresses mood changes, and individuals who do not experience any changes receive 0 points.Reverse coding is applied to questions 1, 4, and 14.Questions 13, 14, and 15 are not included in the scoring process.Te scoring range for diagnosing NES is 0-52, with a cutof score of 25 points or higher indicating the presence of NES.Atasoy et al. [21] conducted a validity and reliability study of the NEQ in Turkish, reporting Cronbach's alpha coefcient of 0.69.In the present study, Cronbach's alpha coefcient for the NEQ was calculated to be 0.68.[22].In the present study, the overall Cronbach's alpha coefcient for the DERS-16 was calculated to be 0.94.

Statistical Analysis.
Descriptive statistics for categorical variables (demographic characteristics) were presented as frequency and percentage.Te Shapiro-Wilk test was used to assess the normal distribution of the data.Since the data were normally distributed, mean (±standard deviation) values were used.Te Levene test was employed to assess the homogeneity of group variances.Te independent sample Ttest was used to compare two independent groups when the data met the assumptions of parametric tests.For comparisons of more than two independent groups, the one-way ANOVA test was utilized if the data met the assumptions of parametric tests and homogeneity tests.Alternatively, the Welch ANOVA test was used.To determine the diferences between groups after the one-way ANOVA test, the Tukey-HSD multiple comparison test was employed.For the Welch ANOVA test, the Tamhane multiple comparison test was used.Te results of the multiple comparison tests were denoted by letters next to the means.Te Pearson productmoment correlation coefcient was utilized to examine the relationships between the scales.Te interpretation of the correlation coefcient was based on the following criteria: "less than 0.2: very weak," "0.2-0.4:weak," "0.4-0.6:medium," "0.6-0.8:strong," and "greater than 0.8: very strong" correlation degree.Cronbach's alpha coefcient was calculated to determine the reliability level of the scales studied.Te statistical signifcance level was considered as "α < 0.05, α < 0.01, and α < 0.001" in all calculations and interpretations, and hypotheses were established as bidirectional.Data analysis was performed using SPSS v26 (IBM Inc., Chicago, IL, USA).being the most prevalent conditions.In addition, 70.3% of the students reported engaging in moderate-intensity physical activity for at least 150 minutes per week or more, as recommended by the World Health Organization (WHO) [23].Surprisingly, 50.3% of these individuals still expressed dissatisfaction with their level of physical activity.Furthermore, the average daily sleep duration for 55.5% of the students fell within the range of 6-8 hours (Table 1).

Women
Te PFS assessment revealed that 68.1% of the students had hedonic hunger, and the NEQ assessment showed that 11.3% had NES.Te mean score of the DERS-16 students was 39.86 ± 14.37 points (Table 2).
In the PSF among the students, it was observed that women had a signifcantly higher mean score compared to men (p < 0.001).Similarly, overweight and obese participants had signifcantly higher mean scores compared to underweight individuals based on BMI (p < 0.001).Furthermore, students who did not engage in regular exercise had higher mean scores compared to those who did exercise (p � 0.016).Moreover, a statistically signifcant negative correlation was found between the age of the students and their total PFS scores although the correlation was very weak (r � −0.083; p < 0.009).Tis suggests that as the age of the students increases, there is an 8.3% decrease in their total PFS scores.In addition, a statistically signifcant positive correlation was observed between BMI and the total PFS scores of the participants, albeit with a very weak strength (r � 0.176; p < 0.001).Tis indicates that as the BMI of the students increases, there is a 17.6% increase in their total PFS scores (Table 3).
Te fndings from the assessment of the NEQ revealed that students who did not engage in regular exercise had a signifcantly higher mean score compared to those who did exercise (p � 0.007).Furthermore, students with a daily sleep duration of less than 4 hours had a signifcantly higher mean score compared to those with a daily sleep duration of 6-8 hours (p � 0.006).In addition, a statistically signifcant positive correlation was observed between the students' BMI and their total NEQ scores although the correlation was very weak (r � 0.079; p � 0.012).Tis suggests that as the BMI of the students increases, their total NEQ scores increase by 7.9% (Table 3).
Te DERS-16 assessment revealed that the mean score of women was statistically signifcantly higher than that of men (p � 0.031) among the students.Furthermore, students with a daily sleep duration of more than 8 hours had a signifcantly higher mean score compared to students with a daily sleep duration between 6 and 8 hours (p < 0.001).Regarding the correlation analysis, a signifcant negative correlation was observed between the age of the students and their total DERS-16 scores although the correlation was very weak (r � −0.065; p < 0.040).Tis indicates that as the age of the students increases, there is a 6.5% decrease in their total DERS-16 scores.In addition, a signifcant positive correlation, albeit very weak, was found between the BMI of the students and their total DERS-16 scores (r � 0.068; p � 0.031).Tis suggests that as the BMI of the students increases, there is a 6.8% increase in their total DERS-16 scores (Table 3).

Perspectives in Psychiatric Care
Te analysis of the data tools revealed signifcant positive weak correlations between the total DERS-16 scores of the students and both the total PSF score (r � 0.325, p < 0.001) and the total NEQ score (r � 0.224, p < 0.001).Tis indicates that as the total DERS-16 score of the students increases, there is a 32.5% increase in the total PSF scores and a 22.4% increase in the total NEQ scores (Table 4).

Discussion
Tis study aimed to investigate the relationship among hedonic hunger, NEQ (Night-Eating Questionnaire), and DER (difculties in emotion regulation) in university students.Te fndings of the study suggest that there is a positive association between the level of difculty experienced in emotion regulation and both hedonic hunger and night-eating tendencies.In other words, as participants faced more challenges in regulating their emotions, they also exhibited higher levels of hedonic hunger and a greater tendency to engage in night-eating behaviors.
Te sample of the study consisted of 1010 participants; approximately 4 out of every 5 participants were women.According to the WHO recommendations [23], approximately 7 out of every 10 participants engaged in moderateintensity physical activity for 150 minutes or more per week and more than half of them had a mean daily sleep duration of 6-8 hours.It was found that approximately 9 out of every 10 students had night-eating syndrome, according to the NES assessment, and 7 out of every 10 students had hedonic hunger.
Among university students, it was found that women exhibit higher levels of DER compared to men.Tis difculty is characterized by challenges in understanding and accepting their emotions, controlling impulsive behaviors, setting goals, and developing efective strategies to achieve those goals.Te existing literature study presents mixed fndings regarding gender diferences in DER.Some studies suggest that women tend to experience higher levels of DER [24,25], while others argue that gender does not play a signifcant role in this regard [26,27].For instance, Ayseli's study reported that women encounter more difculty in maintaining focus during stressful situations, whereas men struggle more with identifying and expressing their emotions [28].Furthermore, women commonly employ an emotion-oriented coping strategy when they perceive the stressor as unchangeable and must be endured.Tis strategy involves focusing on the emotional aspects of the stressor rather than actively seeking to solve the problem.Conversely, men tend to adopt a problem-oriented coping strategy, which aims to address and resolve the source of stress [29].Tese gender diferences in coping strategies may contribute to the observed variations in DER among women.In summary, it is evident that women tend to experience higher levels of DER compared to men in the context of university students.Te diferences in DER may be infuenced by various factors, including coping strategies employed during stressful situations.
Tis study discovered a signifcant negative correlation, with a 6.5% decrease in DERS-16 scores as age increased.Studies in the literature have shown that DER tends to decrease with age [30,31] while others have suggested that age is not a distinguishing factor in emotion regulation [32,33].Te observed decrease in DER scores with age could potentially be attributed to increased life experience and maturity, which contribute to better emotional control.Furthermore, a 6.8% increase in DERS-16 scores was observed as BMI increased.Tis fnding aligns with existing  4 Perspectives in Psychiatric Care literature that individuals with obesity tend to exhibit higher levels of DER [34,35].For instance, a study by Lazarevich et al. involving 1453 university students revealed an association between emotional eating, BMI, and the importance of emotion regulation for maintaining health in young adults [36].Conversely, a study conducted by Monell et al. involving 999 individuals with eating disorders and 252 control subjects found no signifcant relationship between emotion regulation and BMI [37].Another study by Solak Uyar, which focused on 537 female university students aged 18-25, reported no signifcant diferences in DER based on BMI.However, individuals with higher BMI displayed a greater tendency to have negative emotions and engage in emotional eating [38].Tese fndings suggest that DER, infuenced by negative emotions and conditions such as anxiety about the future, socioeconomic issues, and academic success anxiety in university students, may serve as a risk factor for obesity and obesity-related health problems, particularly among individuals prone to emotional eating.According to the WHO recommendations, students who reported not engaging in at least 150 minutes of physical activity per week exhibited borderline high DERS-16 scores (p � 0.051) although this diference was not statistically signifcant compared to those who did meet the recommended activity level.While limited research exists on the direct relationship between exercise duration and DER, studies have explored how exercise or sports impact emotional states.For instance, a study involving 704 young adults found a signifcant positive correlation between the frequency of moderate/vigorous physical activity and happiness, as well as a negative correlation with anxiety/fear, sadness, and anger [39].Other studies in the literature have  Perspectives in Psychiatric Care demonstrated a positive linear relationship regular physical activity and positive moods [40][41][42].Moreover, exercise during the COVID-19 pandemic has been reported to reduce negative mood states such as depression, anxiety [43,44], and stress [45].Tis can be explained by the fact that physical activity and exercise enhance problem-solving abilities, contribute to a positive emotional state, and increase an individual's sense of self-worth, as highlighted in Aylaz et al.'s study.Consequently, physical activity can aid in coping with negative emotions and depressive symptoms by improving psychological resilience and emotion regulation skills [46].Te recommended duration of healthy sleep for optimal mental and physical health typically falls within the range of 6-8 hours although this can vary depending on factors such as age, gender, physical activity level, nutrition, overall health, and environmental conditions [47,48].In the current study, it was observed that students who reported having a daily sleep duration of more than 8 hours exhibited higher levels of DER compared to those with a sleep duration of 6-8 hours.While there is a lack of research specifcally investigating the relationship between sleep duration and DER, existing literature has shown associations between DERS scores and indicators of poor sleep quality [49] and insomnia-related difculties [50].
Te studies mentioned have highlighted that DER can be a contributing risk factor for sleep-related psychiatric conditions, including mood and anxiety disorders.Te sleep-wake cycle is considered the most crucial and infuential circadian rhythm in humans.Disruption of this rhythm can lead to functional impairment in various areas of life, such as social, occupational, academic, and overall mental and physical well-being [51].Prolonged sleep duration, along with negative mood and a tendency to avoid coping with problems, may serve as indicators of difculties individuals face in regulating their emotions.Tese difculties, in turn, can impact sleep patterns and contribute to the development or exacerbation of mental health issues.
Te fndings of this study revealed a signifcant increase in hedonic hunger tendency by 32.5% and nighteating tendency by 22.4% as DER levels increased.While there are no specifc studies examining the direct relationship between DER and NES, research exploring the connection between eating attitudes/disorders and emotion regulation has been investigated.Previous studies have consistently shown that DER is associated with symptoms of eating disorders, and individuals with eating disorders tend to exhibit higher levels of DER [52,53].Specifcally, difculties in emotion regulation, such as low emotional awareness, difculty accepting emotions, and impaired impulse control, have been linked to overeating behaviors [37].Studies focusing on DER and eating disorders have highlighted that individuals with eating disorders often struggle with accepting and understanding their emotions, experiencing emotional ambiguity, and having reduced emotional awareness.Eating disorders are not only solely cognitive and behavioral processes but also involve emotional aspects.DER encompasses not only the understanding and expression of emotions but also the ability to recognize, comprehend, and accept emotions, as well as the capacity to engage in goal-directed behaviors when faced with negative emotions, control impulsive behaviors, and employ adaptive strategies.Tese factors are crucial for maintaining psychological well-being and overall mental health.

Conclusion
Te fndings of this study indicate that there is a signifcant association between increased levels of DER and higher hedonic hunger and night-eating tendencies.Tis suggests that DER plays a signifcant role in the development and maintenance of eating disorders.Tese results have important implications for understanding the underlying factors contributing to eating disorders and informing treatment strategies in therapeutic interventions.By recognizing the infuence of DER on eating behaviors, clinicians and researchers can better understand the complex interplay between emotion regulation and disordered eating.Considering DER as an integral component of eating disorders is crucial for comprehensive assessment, treatment planning, and addressing the emotional aspects of disordered eating.Incorporating interventions that target emotion regulation skills and coping strategies can enhance the efectiveness of interventions aimed at preventing and treating eating disorders.
Te COVID-19 pandemic and the resulting lockdown measures have had signifcant impacts on various aspects of individuals' lives, including university students.Tese circumstances may contribute to the observed associations between DER and eating behaviors.Te prolonged periods spent at home during the lockdown may lead to increased food consumption, even in the absence of physiological hunger, as individuals may turn to food for comfort or as a coping mechanism for stress and negative emotions.Changes in nutrition and sleep patterns during this period may also contribute to a shift in food intake towards evening hours.Moreover, the university age is a period characterized by heightened levels of anxiety and concerns about the future.Tese factors, combined with the challenges posed by the pandemic, may further exacerbate the difculties experienced in emotion regulation and increase the risk of developing eating disorders.Addressing DER and promoting emotion regulation skills in young adults, particularly those at higher risk of developing eating disorders, could have preventive efects.Interventions aimed at enhancing emotion regulation abilities can equip individuals with efective coping strategies, emotional awareness, and adaptive responses to stressors.By empowering young adults with these skills, they may be better equipped to navigate the challenges and emotional distress associated with the university years and mitigate the risk of developing eating disorders.Terefore, comprehensive approaches that target both DER and eating behaviors, taking into account the unique challenges faced during the COVID-19 pandemic, can be benefcial in preventing and addressing eating disorders in university students.6 Perspectives in Psychiatric Care

and Strengths of the Study.
Te limitations of this study are that it was conducted in a single foundation university, the excess of female students (80.4%), and the mean age of university students (21.58 ± 2.98 years).In addition, the fact that the scales used were based on selfreport may have caused the participants to answer the questions with a self-concealing or defensive attitude.To further explore the results of this study, it should be reexamined in diferent samples, such as community-based samples, where there is an excess of male participants.Te strengths and contributions of this study include its focus on a relevant and understudied topic, the use of multiple assessments and measures, the consideration of potential confounding variables, the integration of existing literature, implications for prevention and intervention, and the awareness of limitations and suggestions for future research.Tese strengths enhance the study's value in advancing our understanding of the relationship between emotion regulation and eating behaviors among university students and provide insights for future research and clinical practice.
Te DERS was originally developed by Gratz and Roemer in 2004 to measure individuals' levels of diffculties in emotion regulation (DER).Te short form of the scale, known as DERS-16, was later developed by Bjureberg et al. in 2016.It consists of fve subscales, namely, clarity, impulse, goals, strategy, and nonacceptance.Participants rate their responses to each item on a 16-item Likert-type scale with fve response options, ranging from 1 (almost never) to 5 (almost always).No specifc cutof point has been established for evaluating scale scores.Generally, higher scores on the DERS-16 indicate greater difculties in emotion regulation.Te validity and reliability of the scale in the Turkish language were established by Yigit and Guzey Yigit in 2017, who reported Cronbach's alpha coefcient of 0.92 2Perspectives in Psychiatric Care2.2.3.Difculties in Emotion Regulation Scale-Short Form (DERS-16).

Table 1 :
Demographic characteristics of students.
BMI: Body Mass Index.

Table 2 :
Te scores of PSF, NEQ, and DERS-16 scales of students.

Table 4 :
Correlation coefcient between the scales.Power of Food Scale, NEQ: Night-Eating Questionnaire, DERS-16: Difculties in Emotion Regulation Scale-Short Form, and r: Pearson Product-Moment Correlation.Statistical signifcance level was considered as p < 0.001. PFS: