Fast Food and Its Effects on Physical Health and Psychological Well-Being

Fast Food and Its Effects on Physical Health and Psychological Well-Being

Dr. Sagar Bayaskar

Independent Researcher, India

DOI: https://doi.org/10.51244/IJRSI.2025.120700017

Received: 08 July 2025; Accepted: 11 July 2025; Published: 28 July 2025

ABSTRACT

This study aimed to explore the impact of fast food consumption on both physical health and psychological well-being among adults aged 18 to 45. A qualitative cross-sectional design was adopted, involving 35 participants from diverse educational and occupational backgrounds. Data were collected through in-depth semi-structured interviews and thematically analyzed to identify recurring patterns and individual experiences.

The findings revealed that frequent consumption of fast food was associated with a range of physical health issues, including weight gain (reported by 51% of participants), indigestion (40%), fatigue (29%), and in some cases, elevated blood pressure. Psychologically, 69% of participants described negative effects such as irritability, mood swings, reduced concentration, and feelings of guilt following consumption. Sleep disturbances and reduced daytime energy were also frequently linked to late-night intake of high-calorie, processed meals. Notably, participants who had recently reduced their fast food intake (31%) reported significant improvements in digestion, mood regulation, alertness, and self-esteem.These results suggest that fast food consumption may have compounding effects on both physical and mental health, while dietary improvements can lead to measurable psychological benefits. Public health efforts should therefore address fast food reduction as a strategy for improving overall well-being.

Keywords: Fast food, physical health, psychological well-being, mood disturbances, fatigue, qualitative study, lifestyle habits

INTRODUCTION

The global rise in fast food consumption is a defining feature of modern dietary patterns, particularly among young and working-age populations. Fast food, typically characterized by high levels of fat, sugar, sodium, and calories, is widely favored for its convenience, affordability, and taste appeal. However, the growing reliance on these ultra-processed, ready-to-eat meals has sparked increasing concern among public health experts due to its established link to various lifestyle-related disorders.

Numerous studies have documented the negative physical health consequences of excessive fast food consumption. These include obesity, hypertension, type 2 diabetes, cardiovascular diseases, and gastrointestinal issues (Pereira et al., 2005; Rosenheck, 2008). The energy-dense, nutrient-poor composition of such meals contributes to weight gain and metabolic dysfunction, especially when combined with sedentary behavior. Despite this awareness, consumption continues to rise globally, driven by urbanization, time constraints, and aggressive food marketing.

In recent years, attention has also turned to the psychological consequences of fast food intake. Emerging evidence suggests that diets high in processed foods may be associated with increased risk of mental health issues such as depression, anxiety, irritability, and cognitive fatigue (Jacka et al., 2010; Lassale et al., 2019). The mechanisms proposed include inflammation, hormonal imbalance, and disruption of gut-brain communication. However, much of the existing research remains quantitative, with limited exploration of individuals lived experiences and subjective perceptions of how fast food affects their mental and emotional states.

Understanding the impact of fast food on both physical and psychological dimensions is essential for holistic health promotion. This study aims to explore these effects qualitatively, focusing on how regular consumption of fast food influences physical health outcomes such as weight and energy, as well as psychological factors like mood, focus, and stress. By capturing participant experiences, the study seeks to contribute deeper insights into the complex relationship between diet and overall well-being, which can inform future interventions and public awareness campaigns

REVIEW OF LITERATURE

Fast Food and Physical Health

Fast food is typically high in saturated fats, trans fats, sodium, and refined sugars, while being low in essential nutrients and dietary fiber. These poor nutritional characteristics significantly contribute to the development of non-communicable diseases such as obesity, diabetes, and cardiovascular disorders. Pereira et al. (2005) demonstrated a strong correlation between frequent fast food consumption and increased weight gain and insulin resistance over a 15-year period. Similarly, Rosenheck (2008) emphasized that the regular intake of energy-dense, processed meals is associated with higher overall caloric intake and an elevated risk of obesity.

A study by Bowman and Vinyard (2004) noted that individuals who consumed fast food more than twice a week were at greater risk of developing hypertension and cardiovascular diseases. High sodium content in fast food has also been linked to elevated blood pressure and poor heart health (He et al., 2013). Additionally, fast food consumption has been associated with gastrointestinal issues such as bloating, constipation, and acid reflux due to poor-quality fats and low dietary fiber (Paeratakul et al., 2003).

Fast Food and Psychological Well-being

The ultra-processed food intake is associated with poor mental health, potentially mediated by inflammation, oxidative stress, altered gut microbiota, and disrupted neurotransmitter pathways. These mechanisms suggest that poor dietary quality may contribute to emotional dysregulation and increased psychological distress Lassale et al. (2019);Khalid et al. (2020).

A large-scale meta-analysis by Lassale et al. (2019) confirmed that diets rich in fruits, vegetables, whole grains, and lean proteins were protective against depression, while Western-style diets—typified by fast food—were linked to a higher risk of mental health disorders. Additionally, Tanaka et al. (2018) found that increased fast food intake was associated with poor sleep quality, which indirectly affects mood, concentration, and emotional regulation.

Moreover, emotional eating—using food as a coping mechanism for stress or boredom—is more commonly associated with fast food consumption. Neumark-Sztainer et al. (1999) and Larson et al. (2009) reported that adolescents and young adults often resort to fast food during emotional distress, leading to a cycle of poor dietary behavior and declining psychological health.

Combined Impact on Overall Well-being

Recent research increasingly acknowledges the interconnectedness of physical and psychological health. Fast food consumption not only contributes to weight gain and metabolic dysfunction but also negatively impacts self-image, emotional regulation, and cognitive performance. Sleep disturbances caused by high-calorie, late-night meals can further reduce daytime alertness and mood stability (St-Onge et al., 2016). Individuals who frequently consume fast food may also experience feelings of guilt or regret, further compounding psychological distress.

Despite growing evidence, most studies on fast food and health outcomes rely heavily on quantitative data. There is a need for qualitative approaches that capture the lived experiences and subjective perceptions of individuals. Understanding how people interpret and feel the effects of fast food on their bodies and minds can provide a more comprehensive view of its health implications.

Rationale for the Present Study

While existing literature strongly supports the link between fast food and adverse physical and mental health outcomes, limited research explores these effects through qualitative narratives. This study aims to fill that gap by examining how individuals experience the dual impact of fast food consumption—physically and psychologically—and how changes

METHODOLOGY

Study Design

This study employed a qualitative, cross-sectional design to explore the perceived effects of fast food consumption on physical health and psychological well-being. A qualitative approach was chosen to capture in-depth, personal insights from individuals regarding their dietary habits, health experiences, and emotional responses associated with fast food intake.

Study Population and Sampling

A total of 35 participants, aged between 18 and 45 years, were purposively selected using maximum variation sampling to ensure diversity in age, gender, education, and occupation. The inclusion criteria required participants to have a history of regular fast food consumption (defined as more than twice a week) and a willingness to share their experiences. Participants were recruited from both urban and semi-urban areas in Maharashtra, India, to reflect a range of socio-cultural and lifestyle contexts.

Data Collection

Data were collected through in-depth, semi-structured interviews conducted either face-to-face or via telephone/online platforms, depending on participant preference and convenience. An interview guide was developed to explore key domains, including frequency and reasons for fast food intake, perceived physical effects (e.g., weight gain, fatigue, digestion), psychological responses (e.g., mood changes, concentration, sleep), and any observed changes after reducing consumption.

Each interview lasted approximately 30 to 45 minutes. All interviews were audio-recorded with participant consent and supplemented by field notes. To ensure authenticity, responses were transcribed verbatim, and any identifying information was removed to maintain confidentiality.

Data Analysis

Thematic analysis was used to analyze the qualitative data. Transcripts were read repeatedly to familiarize the researchers with the content. Codes were generated inductively and grouped into broader categories to identify recurring patterns and themes. The analysis focused on three primary outcome areas: (1) physical health experiences, (2) psychological impacts, and (3) behavioral or lifestyle changes after dietary modifications. NVivo software was used to assist in organizing and managing the coding process.

Ethical Considerations

Ethical approval was obtained from the Institutional Ethics Committee prior to data collection. Informed consent was obtained from all participants, and they were assured of the voluntary nature of participation, confidentiality of their responses, and their right to withdraw at any stage without consequence. No financial compensation was provided to participants.

RESULTS

Physical Health Effects

A majority of participants (77%; 27 out of 35) reported experiencing physical health issues due to frequent consumption of fast food. The most common complaints included weight gain, bloating, indigestion, and low physical stamina. One participant noted, “Whenever I eat outside food for more than two or three days, I feel heavy, and my stomach gets upset easily” (Female, 29 years).

Eighteen participants specifically mentioned an increase in body weight or body fat, while 14 described symptoms of indigestion, and 10 reported persistent fatigue. These effects were more pronounced in participants consuming fast food more than three times a week. A 33-year-old male participant stated, “Earlier I used to feel more energetic, but now after regular fast food, I feel sleepy and tired quickly.”

Additionally, a small group (n=5) reported elevated blood pressure or recurring acidity after high-sodium fast food meals, especially when paired with sugary beverages or fried items.

Psychological and Emotional Impact

Psychological effects were reported by 69% (24 out of 35) of the participants. These included mood swings, irritability, low motivation, and reduced concentration. Many described a pattern where fast food offered short-term pleasure but was followed by emotional discomfort. One participant shared, “I feel good for a short time after eating it, but later I regret it—mentally I feel sluggish and lazy” (Male, 26 years).

Thirteen participants admitted experiencing frequent mood swings, while 16 noted irritability and emotional instability. Emotional eating was commonly reported, particularly under stress or fatigue. “When I’m stressed, I automatically order fast food. But afterward, I feel even more drained and anxious,” reflected a 24-year-old female.

Eleven participants described feeling mentally dull or unable to concentrate, particularly during study or work hours following a fast food-heavy diet. Some even compared the psychological impact of fast food to a “mental crash” following initial gratification.

Table 1: Reported Physical and Psychological Effects of Fast Food Consumption

Health Impact	Number of Participants (n=35)	Percentage (%)
Physical Health Effects
Weight gain	18	51%
Indigestion / bloating	14	40%
Fatigue / Low stamina	10	29%
Elevated blood pressure	5	14%
Psychological Effects
Mood swings / Irritability	16	46%
Poor concentration / brain fog	11	31%
Feelings of guilt after eating	9	26%
Stress-triggered eating behavior	17	49%
Sleep disturbances	22	63%

Sleep Patterns and Energy Levels

Sleep disruption was another recurring theme, with 63% (22 out of 35) reporting poor sleep quality related to late-night fast food consumption. High-calorie meals consumed in the evening were associated with shallow sleep, restlessness, and difficulty waking refreshed. “I sleep late and often after eating snacks. I don’t sleep deep and wake up tired,” reported a 30-year-old female.

Male participants aged 18–30 commonly shared that they relied on tea or energy drinks to compensate for next-day fatigue. “Whenever I skip home-cooked meals and eat burgers at night, I wake up feeling drained,” said a 21-year-old engineering student. Participants also noted low motivation to engage in physical activity, attributing it to both sleep deprivation and poor diet.

Improvements After Dietary Changes

Among the 11 participants (31%) who had reduced fast food intake in the past three months, 9 reported clear improvements in physical and psychological well-being. Benefits included better digestion (n=8), increased energy (n=7), and improved focus or mood stability (n=6). One participant described, “Since I started eating home food again, I feel lighter and sleep much better” (Female, 32 years).

Participants also reported enhanced self-esteem and a stronger sense of control over their lifestyle. A 27-year-old male shared, “My focus has improved. I don’t feel that afternoon crash anymore.” Many of these individuals expressed greater satisfaction with their daily routines and were motivated to maintain healthier habits.

Figure1: Participant-Reported Improvements After Reducing Fast Food Intake

DISCUSSION

The findings of this study provide important insights into how fast food consumption affects both physical health and psychological well-being, as perceived by young and middle-aged adults. Participants frequently reported physical symptoms such as weight gain, digestive issues, fatigue, and low energy—findings that align with existing research linking fast food intake to obesity, metabolic disturbances, and gastrointestinal discomfort (Pereira et al., 2005; Bowman & Vinyard, 2004). The energy-dense and nutrient-poor nature of fast food appears to play a significant role in disrupting metabolic balance, especially when consumed frequently and in large portions.

The psychological impact of fast food was also notable, with many participants reporting mood swings, irritability, decreased focus, and emotional fatigue. These experiences resonate with earlier studies suggesting that Western-style diets are associated with increased risk of depression and anxiety (Jacka et al., 2010; Lassale et al., 2019). The short-term pleasure or stress relief derived from fast food was often followed by feelings of guilt or low mood, reflecting patterns of emotional eating and dietary regret Such findings are consistent with the concept of ‘hedonic hunger,’ which refers to the desire to eat for pleasure rather than to satisfy physiological hunger, often triggered by the sight, smell, or thought of palatable foods. where highly palatable foods activate reward pathways but do not provide lasting emotional satisfaction (Lutter & Nestler, 2009).

An additional and significant finding was the reported disruption of sleep patterns and lowered daytime alertness following heavy or late-night fast food intake. This aligns with previous work showing that high-fat and high-sugar diets can negatively affect sleep quality, possibly through inflammation, hormonal imbalance, and poor digestion (St-Onge et al., 2016; Tanaka et al., 2018). Sleep quality, in turn, has been shown to affect cognitive performance, mood regulation, and emotional resilience, further reinforcing the cyclical impact of poor dietary habits on mental well-being (Chaput, 2014).

Importantly, participants who had reduced their fast food intake in recent months reported notable improvements in both physical vitality and emotional regulation. This suggests that dietary changes—even in the short term—can positively influence overall health. Such findings are encouraging and support prior research demonstrating the psychological benefits of improved diet quality, including increased mental clarity, better sleep, and improved mood stability (Opie et al., 2015; Firth et al., 2020).

The study contributes to the existing body of literature by providing qualitative evidence on the lived experiences of individuals affected by fast food consumption. Unlike quantitative surveys, in-depth interviews allowed for a nuanced understanding of behavioral motivations, emotional responses, and personal health narratives. While most existing studies focus on physical biomarkers or depression scales, this study highlights the subjective burden of dietary habits on everyday well-being, offering real-world relevance for health education and dietary intervention programs.

However, these findings must be interpreted with caution due to the study’s limitations, including self-reported data and a non-random sample. Nonetheless, the results underscore the need for public health initiatives that not only address the nutritional risks of fast food but also consider its psychological and behavioral implications. A more integrated approach to dietary counseling could enhance both physical and mental health outcomes, particularly in youth and working populations.Top of Form

CONCLUSION

This study underscores the multifaceted impact of frequent fast food consumption on both physical health and psychological well-being. Participants reported a range of physical issues such as weight gain, digestive discomfort, and fatigue, alongside psychological challenges including mood swings, reduced concentration, sleep disturbances, and emotional distress. Notably, individuals who reduced their intake of processed, ready-to-eat meals reported improvements in energy levels, emotional balance, sleep quality, and overall lifestyle satisfaction.

These findings highlight the critical need for public health interventions that go beyond addressing the nutritional content of fast food and instead adopt a more holistic view of diet and mental health. Educating individuals—especially young adults—about the long-term consequences of poor dietary habits and promoting access to healthier, affordable food options can significantly improve both physical and psychological well-being. Future studies should explore this relationship further using mixed methods and include objective health indicators to strengthen evidence for action.

Limitations

This study is limited by its small, purposively selected sample and reliance on self-reported data, which may introduce recall or response bias. As a qualitative study, it does not establish causality and may not be generalizable to all populations.

Future Implications

Future research should include larger, diverse samples and mixed-method approaches to validate these findings. Public health strategies should address both the physical and psychological impacts of fast food consumption and promote healthier dietary behaviors through education and policy interventions.

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