This systematic review and meta-analysis assessed the socioeconomic, psychological, and environmental factors influencing healthy food consumption in the USA. A total of 90 studies were included, following a comprehensive screening process, and the findings were synthesized using qualitative thematic analysis and quantitative meta-analysis. The results show that socioeconomic factors, particularly income and education, significantly impact dietary choices. Individuals from lower-income groups were 28% less likely to consume healthy foods (pooled OR = 0.72; 95% CI: 0.65–0.80). The high cost of nutritious food and time constraints were identified as significant barriers. Psychological factors, including health consciousness and self-efficacy, were also important, with individuals with low health awareness being 38% less likely to consume healthy foods (pooled OR = 0.62; 95% CI: 0.55–0.70). Environmental factors, particularly food accessibility, were critical, as individuals in food deserts were 43% less likely to consume healthy foods (pooled OR = 0.57; 95% CI: 0.50–0.65). The findings underscore the need for multi-faceted policy interventions, such as subsidies for healthy foods, expanded nutrition education, and improved access to affordable, nutritious food in underserved areas. Addressing these barriers holistically could improve the dietary habits of diverse populations across the USA.

Healthy food consumption is essential for maintaining optimal health and preventing diet-related chronic conditions, which have been on the rise in the United States (Micha et al., 2017). Despite growing awareness of the importance of a balanced diet, many Americans consume foods high in calories, sugar, and unhealthy fats while falling short of the recommended intake of fruits, vegetables, whole grains, and lean proteins (USDA, 2020). This imbalance is influenced by various factors, including socioeconomic status, psychological drivers, and environmental conditions. Understanding these factors is critical to developing targeted interventions to help individuals overcome barriers to healthy eating and promote better public health.

This paper presents a systematic review and meta-analysis of the factors affecting healthy food consumption in the USA. By examining socioeconomic, psychological, and environmental determinants, this research seeks to provide a comprehensive understanding of how these factors interact to influence dietary behaviour. The findings of this review are intended to inform policymakers, healthcare professionals, and community organizations in designing more effective interventions to improve nutritional habits across different population groups.

Background:

Healthy eating is directly linked to reduced risks of chronic diseases, such as heart disease, diabetes, and obesity, which have become leading causes of mortality in the United States (Micha et al., 2017). However, income inequality, lack of education, and restricted access to healthy food options often limit healthy food consumption. Socioeconomic factors such as income and education have been shown to play a significant role in determining the quality of an individual's diet, with lower-income populations often consuming fewer healthy foods due to the higher costs of nutritious items (Darmon & Drewnowski, 2008). Similarly, psychological factors like health consciousness and self-efficacy influence whether individuals choose healthier foods (Kellar & Abraham, 2005). Additionally, environmental factors such as food deserts, where access to supermarkets and fresh produce is limited, further complicate the ability of specific populations to maintain a healthy diet (Walker et al., 2010).

This systematic review seeks to explore the extent to which these socioeconomic, psychological, and environmental factors impact food consumption in the USA. By identifying key patterns and discrepancies across various studies, this review aims to comprehensively understand the issue and provide evidence-based recommendations for improving dietary habits across diverse populations.

Objective:

The primary objective of this systematic review and meta-analysis is to investigate the factors that influence healthy food consumption in the USA, focusing on socioeconomic, psychological, and environmental determinants. This study aims to:

1. Quantify the effects of income, education, and food accessibility on healthy food consumption through meta-analysis.
2. Identify psychological barriers that impact dietary behaviour, such as health consciousness and self-efficacy.
3. Examine environmental influences that restrict or facilitate access to healthy foods, including food deserts and marketing.
4. Provide actionable insights and recommendations for policymakers and healthcare professionals based on the synthesis of current evidence.

This paper is organized into several key sections, each addressing different aspects of the systematic review and meta-analysis. Section 1: Introduction and Background: This section provides an overview of the importance of healthy food consumption, explains the factors influencing dietary habits, and outlines the scope of the review. It also presents the research objective and the paper's structure, helping the reader understand the rationale behind the study and the anticipated outcomes. Section 2: Methods: This section details the methodology used to conduct the systematic review and meta-analysis. It outlines the databases searched, the inclusion and exclusion criteria applied to select studies, and the data extraction process. This section will also explain how the meta-analysis was performed and the tools used to assess the quality of the included studies. Section 3: Results: This section presents the findings from the meta-analysis and qualitative synthesis. It highlights each factor's critical socioeconomic, psychological, and environmental results. Forest plots and tables summarizing the pooled odds ratios (OR) for various aspects will be included to provide a clear understanding of the quantitative analysis. Section 4: Discussion: The discussion interprets the review's findings and compares them with existing literature. This section explores the consistency and discrepancies across the studies and explains why certain factors may have more potent effects than others. It evaluates the practical and policy implications of the results and suggests areas for future research. Section 5: Limitations: This section acknowledges the limitations of the review, such as potential biases, variations in study design, and the heterogeneity of the included studies. It also discusses the limitations of the meta-analysis in establishing causality, considering that many of the included studies are observational. Section 6: Conclusion: The conclusion summarizes the key findings of the review and their implications for improving healthy food consumption in the USA. It emphasizes addressing socioeconomic disparities, enhancing psychological drivers like health consciousness, and improving access to nutritious foods in underserved areas. Recommendations for policymakers and healthcare providers are also provided

This section details the comprehensive methodology for this systematic review and meta-analysis on the factors affecting healthy food consumption in the USA. Following PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines, the study systematically identified, selected and assessed studies that explored socioeconomic, psychological, and environmental determinants of healthy food consumption. The rigorous methods ensured that relevant, high-quality studies were synthesized qualitatively and quantitatively, providing insights into critical factors influencing dietary behaviour.

Research Design

The research design follows a structured approach combining qualitative thematic synthesis and quantitative meta-analysis. This methodology allows us to explore patterns and effect sizes associated with healthy food consumption determinants. The overall design seeks to assess the following:

1. Socioeconomic factors: Income, education, employment.
2. Psychological factors: Health consciousness, self-efficacy, perceived barriers.
3. Environmental factors: Food accessibility, food deserts, marketing influences.

The design follows a multi-phase process, including study identification, eligibility screening, quality assessment, and data extraction, culminating in evidence synthesis.

Figure 1. Conceptual Research Design 

This conceptual diagram illustrates how the independent factors (socioeconomic, psychological, and environmental) affect the dependent variable, healthy food consumption.

Search Strategy

A comprehensive search strategy was developed to ensure the retrieval of all relevant studies. The search was designed to cover a broad range of databases and included studies published between January 2000 and September 2024. The strategy incorporated Boolean operators and precise search terms to refine the search results.

Databases Searched

The following databases were chosen for their comprehensive coverage of nutrition, health, psychology, and public health research:

1. PubMed: Provides extensive access to health-related research, including nutrition and dietary behaviour.
2. Scopus: A multidisciplinary database covering social sciences, health sciences, and behavioural research.
3. Web of Science: Includes high-quality peer-reviewed journals across diverse fields.
4. Google Scholar: Used to capture additional grey literature, including policy papers, reports, and dissertations.

Search Terms

The search terms used in this study were a combination of MeSH terms and keywords applied using Boolean operators (AND, OR, NOT) to capture studies on healthy food consumption in the USA. The following is an example of the search strategy:

("Healthy food consumption" OR "Diet quality" OR "Nutritional intake") AND 

("Socioeconomic factors" OR "Income" OR "Education" OR "Employment") AND 

("Psychological factors" OR "Health consciousness" OR "Self-efficacy") AND 

("Food accessibility" OR "Food deserts" OR "Supermarket proximity") AND 

("United States" OR "USA")

The search yielded 2500 studies, further filtered based on predefined inclusion and exclusion criteria.

The following diagram illustrates the stepwise search process leading to the final pool of included studies:

Figure 2. Search Process

This diagram details the process from initial search results to the final inclusion of studies for analysis.

Inclusion and Exclusion Criteria

Predefined inclusion and exclusion criteria were applied to ensure that the studies included in the review were both relevant and of high quality.

Inclusion Criteria:

• Population: Studies conducted in the USA focused on general adult populations or subgroups defined by socioeconomic, psychological, or environmental characteristics.
• Study Type: Observational studies (e.g., cross-sectional, cohort, case-control) and qualitative research that provided primary data on healthy food consumption.
• Outcomes: Studies that reported measurable outcomes such as fruit/vegetable intake, whole grain consumption, or overall diet quality linked these outcomes to socioeconomic, psychological, or environmental factors.
• Publication Timeframe: Studies published between January 2000 and September 2024.
• Language: Only studies published in English.

Exclusion Criteria:

• Non-USA Studies: Studies conducted outside the USA were excluded to maintain focus on the American dietary context.
• Clinical Interventions: Clinical trials focusing on pharmacological or therapeutic interventions unrelated to population dietary habits were excluded.
• Insufficient Data: Studies without sufficient quantitative data or appropriate statistical analysis were excluded.

Data Extraction Process

The data extraction process followed a structured approach to ensure accuracy and consistency. Two independent reviewers extracted relevant data using a standardized form. Discrepancies were resolved through discussion, with the final data approved by consensus.

Data Extraction Items:

1. Study characteristics: Author(s), year of publication, and journal.
2. Population details: Sample size, demographics (age, gender, socioeconomic status).
3. Independent Variables: Socioeconomic (income, education), psychological (health consciousness, self-efficacy), environmental (food deserts, access to supermarkets).
4. Outcome Variables: Measures of healthy food consumption (fruit/vegetable intake, whole grain consumption).
5. Statistical Data: Odds ratios (OR), relative risks (R.R.), and 95% confidence intervals (CI).

Table 1: Data Extraction Example.

Mathematical Foundation for Meta-Analysis

Meta-analysis was performed to pool effect sizes from individual studies, using odds ratios (OR) and relative risks (R.R.) to quantify the association between the identified factors and healthy food consumption. The following mathematical models were employed:

Pooled Odds Ratio (OR) Calculation: The pooled odds ratio was calculated using the following weighted formula:

Where:

• Is the odds ratio of the study.
• Is the weight assigned to the study, typically based on the inverse variance of the odds ratio.
• is the total number of studies included in the meta-analysis.

Heterogeneity Testing.

To assess the consistency of results across studies, Cochran's test and the statistic was calculated to measure the degree of heterogeneity.

Where:

• is Cochran's statistic.
• is the number of studies.
• represents the percentage of total variation across studies due to heterogeneity rather than chance.

Quality Assessment Tool

To ensure that only high-quality studies were included, two well-established tools were employed for quality assessment:

Newcastle-Ottawa Scale (NOS): Used to assess observational studies across three domains—selection, comparability, and outcome.

Cochrane Risk of Bias Tool: Applied to randomized studies, this tool evaluates potential biases across five domains: selection, performance, detection, attrition, and reporting.

Figure 3: Quality Assessment Framework

This diagram illustrates the quality assessment process for selecting studies based on their methodological rigour. Studies were scored based on these criteria to ensure that only high-quality studies contributed to the meta-analysis.

Pooled Analysis and Results

After extracting the data, the selected studies were pooled for quantitative synthesis. Meta-analysis was performed to determine the strength of associations between socioeconomic, psychological, and environmental factors and healthy food consumption outcomes.

The equation for Pooled Effect Size

The inverse variance weighting method was applied to compute the pooled effect size. This approach gives more weight to studies with larger sample sizes and less variance, ensuring that the pooled effect size is robust and reliable. The equation for calculating the pooled relative risk (R.R.) is as follows:

Where:

• is the relative risk of the study.
• Is the weight assigned to the study based on its variance.
• is the total number of studies included in the meta-analysis.

A forest plot was generated to visually represent the results of the meta-analysis, summarizing the effect sizes of the individual studies and the overall pooled effect size

Figure 4. Forest Plot for Meta-Analysis

This forest plot visualizes the odds ratios (OR) and confidence intervals (CI) for individual studies, providing a clear overview of the pooled analysis. Studies with larger sample sizes or lower variance have greater weight in determining the pooled effect.

Heterogeneity and Sensitivity Analysis

To assess the variability among the studies included in the meta-analysis, we calculated Cochran's Q and statistics. The results of the heterogeneity test are as follows:

• Cochran's Q: , indicating the presence of moderate heterogeneity.
• Statistic:  , which suggests that about of the variability across studies is due to heterogeneity rather than chance.

Sensitivity analysis was performed to account for this heterogeneity by excluding outliers and recalculating the pooled effect size. This ensured that no single study unduly influenced the overall result.

The methodological approach taken in this systematic review and meta-analysis was comprehensive and rigorous. A straightforward search strategy, well-defined inclusion/exclusion criteria, structured data extraction, and robust quality assessment ensured that only high-quality studies contributed to the final meta-analysis. The study provides reliable insights into the socioeconomic, psychological, and environmental factors influencing healthy food consumption in the USA by employing advanced statistical techniques such as the inverse variance method and conducting heterogeneity and sensitivity analyses. These methods form the foundation for interpreting the results in the subsequent sections.

For this systematic review and meta-analysis on factors affecting healthy food consumption in the USA, a rigorous selection process was followed. Initially, a broad search of multiple academic databases was conducted, including PubMed, Scopus, and Web of Science. The search identified 2,500 studies on healthy food consumption, dietary habits, and influencing factors in the USA.

• 2,500 studies were initially identified through the database search.
• After removing 400 duplicate records, 2,100 studies remained.
• A title and abstract screening eliminated 1,500 studies, leaving 600 full-text articles for detailed review.
• Following the full-text review, 450 studies were excluded based on the exclusion criteria, resulting in a final pool of 90 studies in the meta-analysis and thematic analysis.

This detailed process ensures that only the most relevant and high-quality studies are included in the final analysis, providing robust and reliable conclusions.

Grouping Studies Based on Thematic Factors

1. Socioeconomic factors: Income, Education.
2. Psychological factors: Health consciousness, Self-efficacy.
3. Environmental factors: Food accessibility and availability of healthy options (e.g., food deserts).

Thematic Analysis Results by Factor

The thematic analysis will involve extracting recurring qualitative themes that complement and explain the quantitative findings of the meta-analysis. We will identify barriers, motivators, and patterns discussed across the literature for each factor.

1. Socioeconomic Factors

In addition to the quantitative results (OR = 0.72, 95% CI: 0.65–0.80) showing lower-income individuals are less likely to consume healthy foods, the thematic analysis of the studies highlights:

• Cost of Healthy Foods: Several studies mentioned that healthier options (e.g., fresh fruits, vegetables, and lean proteins) are more expensive than processed or calorie-dense foods, creating a financial barrier for low-income families. This theme recurred in almost all studies on socioeconomic status.
• Time Constraints: Lower-income individuals often work longer or more irregular hours, leaving less time for preparing home-cooked meals. Convenience foods, usually unhealthy, are preferred as they require minimal preparation time.
• Limited Access to Nutrition Education: Education about the benefits of healthy eating is limited in lower-income communities. The studies suggest that many people are unaware of how to make healthier choices or how to prepare affordable, nutritious meals.

Table 2: Key Thematic Factors Related to Socioeconomic Status

2. Psychological Factors

In the meta-analysis, health consciousness was found to have an OR of 0.62 (95% CI: 0.55–0.70), suggesting that individuals with lower health awareness are 38% less likely to consume healthy food. The thematic analysis of qualitative data across studies identified:

• Perceived Health Benefits: People with high health consciousness tend to view food choices through the lens of long-term health benefits, whereas those with lower awareness often prioritize immediate satisfaction, convenience, and cost.
• Self-Efficacy: Many individuals reported feeling unsure of their ability to follow healthy eating habits consistently, mainly if they grew up in environments where unhealthy eating was the norm.

Taste Preferences: A recurring theme was that those with lower health consciousness are more driven by taste preferences, which often favour calorie-dense, highly processed foods over healthier alternatives.

Table 3. Key Thematic Factors Related to Psychological Aspects

3. Environmental Factors

In the meta-analysis, individuals living in areas with low food accessibility had an OR of 0.57 (95% CI: 0.50–0.65), showing they are 43% less likely to consume healthy foods. The thematic analysis adds more nuanced insights:

• Food Deserts: Many studies highlighted the concept of food deserts—areas where healthy food is scarce or prohibitively expensive. Residents of these areas often rely on convenience stores or fast food outlets, which rarely offer healthy options.
• Social Environment: The local social environment is critical in food choices. In communities where unhealthy eating is normalized, individuals are more likely to make similar choices, especially in areas where unhealthy food options are more prevalent than healthier alternatives.
• Marketing and Store Layout: Marketing practices and the layout of stores in low-income areas were less conducive to healthy choices. Processed and sugary foods are often promoted more aggressively, and more nutritious options are harder to find or less visible in these stores.

Table 4. Key Thematic Factors Related to Environmental Factors

Prevalence of Thematic Factors Affecting Healthy Food Consumption in the USA.

Figure 5. Bar Chart of Thematic Factors Frequency

This bar chart visualizes the prevalence of critical thematic factors identified across the literature:

• The cost of Healthy Foods (90%) is the most frequently mentioned theme, highlighting that the expense of healthy foods is a significant barrier for many individuals.
• Food Deserts (80%) is another prominent theme, indicating that environmental factors significantly determine food choices, particularly in communities with limited access to healthy foods.
• Perceived Health Benefits (85%) is a recurring psychological factor where individuals prioritizing long-term health outcomes are more likely to consume healthy foods.

Meta-Analysis Results by Factor

Socioeconomic Factors

The Odds Ratio (OR) for the relationship between income and healthy food consumption shows that individuals from lower-income groups are less likely to consume healthy food compared to higher-income groups. The pooled OR is 0.72 (95% CI: 0.65–0.80), indicating that lower-income individuals are approximately 28% less likely to consume healthy food.

Table 5. Meta-Analysis of Income Impact on Healthy Food Consumption

Figure 6. Forest Plot for Income Impact

In the forest plot, each point represents the odds ratio (OR) from an individual study, while the horizontal lines represent the 95% confidence intervals (CI).

The vertical dashed line at OR = 1 represents no effect. The result is not statistically significant if a study's confidence interval crosses this line. In this case, all the studies' confidence intervals are on the left side of 1, indicating that lower-income individuals are less likely to consume healthy foods compared to higher-income individuals across all studies. The pooled result at the bottom (OR = 0.72) summarizes the overall effect of income on healthy food consumption, showing that income plays a significant role in healthy eating behaviours.

2. Psychological Factors

Health-conscious individuals are significantly more likely to consume healthy food. The pooled OR is 0.62 (95% CI: 0.55–0.70), meaning people with low health consciousness are about 38% less likely to choose healthy food options.

Table 6. Meta-Analysis of Health Consciousness Impact on Healthy Food Consumption

Figure 7. Forest Plot for Health Consciousness Impact

Each study's odds ratio (OR) and confidence intervals (CI) are plotted to reflect the effect of health consciousness on healthy food consumption. All studies have an OR below 1, meaning that people with low health consciousness are significantly less likely to consume nutritious foods. The pooled OR of 0.62 suggests a 38% lower likelihood of healthy food consumption among individuals with low health consciousness. The consistency of the results across the studies strengthens the conclusion that health consciousness plays a crucial role in determining food choices.

3. Environmental Factors

The pooled OR of 0.57 (95% CI: 0.50–0.65) shows that individuals who live farther away from stores selling healthy food are 43% less likely to consume nutritious foods, highlighting the importance of proximity and food access in dietary choices.
 

Table 7. Meta-Analysis of Food Accessibility Impact on Healthy Food Consumption

Figure 8. Forest Plot for Food Accessibility Impact

The odds ratios and confidence intervals for each study demonstrate that individuals living farther from healthy food stores (or in "food deserts") are less likely to consume nutritious foods. The pooled OR of 0.57 indicates that people in areas with poor food accessibility are 43% less likely to consume healthy food than those in better-accessed areas. The confidence intervals for all studies fall below 1, confirming a statistically significant association between food accessibility and nutritious food consumption.

Summary of Meta-Analysis Results

Socioeconomic Factors: Lower income groups have an OR of 0.72 for healthy food consumption, suggesting they are 28% less likely to consume healthy foods. Psychological Factors: Low health consciousness is associated with a 38% lower likelihood of consuming healthy foods (pooled OR: 0.62). Environmental Factors: People living farther from stores selling healthy food are 43% less likely to consume healthy foods (pooled OR: 0.57). These factors play a significant role in shaping dietary habits, with socioeconomic status, psychological awareness, and physical access to healthy food being critical determinants.

Combining meta-analysis and thematic analysis, we understand the factors affecting healthy food consumption in the USA. Socioeconomic factors include the cost of nutritious foods and lack of time, which are vital barriers for low-income individuals. Psychological factors: Low health consciousness and self-efficacy reduce the likelihood of making healthy food choices. Environmental factors: Living in food deserts and being influenced by social and marketing environments further hinder access to and consumption of nutritious food. Together, these analyses provide a nuanced picture of the quantitative impact of various factors and the qualitative experiences of different populations.

This systematic review and meta-analysis aimed to investigate the factors affecting healthy food consumption in the USA, focusing on socioeconomic, psychological, and environmental determinants. The findings provide insight into the complex interplay between these factors and suggest critical areas for intervention to improve healthy eating behaviours. This section will interpret the key findings, analyze the consistency and discrepancies across studies, discuss the implications for policy and practice, and outline the limitations of the review.

Interpretation of Findings

The meta-analysis revealed that all three factors—socioeconomic, psychological, and environmental—significantly impact healthy food consumption. Socioeconomic status (SES), particularly income and education level, emerged as a strong determinant. Individuals with higher income levels were more likely to consume healthy food, consistent with the pooled odds ratio (OR) of 0.72 (95% CI: 0.65–0.80), indicating that low-income individuals are approximately 28% less likely to consume healthy foods. This is in line with previous research suggesting that the high cost of nutritious foods, such as fresh fruits, vegetables, and lean proteins, acts as a barrier to lower-income groups (Drewnowski & Darmon, 2005; Darmon & Drewnowski, 2008). In addition, low-income individuals often face time constraints that limit their ability to prepare healthy meals and limited access to nutrition education (Kirkpatrick & Tarasuk, 2011).

Psychological factors also play a crucial role in food choices, as evidenced by the association between health consciousness and healthy eating habits. The pooled OR of 0.62 (95% CI: 0.55–0.70) indicates that individuals with lower health consciousness are 38% less likely to consume healthy foods. This finding aligns with studies showing that individuals who are more aware of the long-term health consequences of their dietary choices are more likely to make healthier food selections (Glanz et al., 1998; Povey et al., 2000). Moreover, the theme of self-efficacy—confidence in one's ability to maintain healthy eating habits—was a recurring theme in the literature. Individuals with low self-efficacy were less likely to consume healthy foods, likely due to a lack of familiarity with healthy cooking practices or perceived difficulties in sustaining a balanced diet (Bandura, 1997; Kellar & Abraham, 2005).

The environmental factors highlighted in this review, particularly food accessibility and the prevalence of food deserts, were found to have a profound impact on dietary behaviours. The pooled OR of 0.57 (95% CI: 0.50–0.65) suggests that individuals in food deserts or areas with low access to healthy food are 43% less likely to consume nutritious foods. This is consistent with research demonstrating that geographical barriers, such as the absence of supermarkets in low-income neighbourhoods, force residents to rely on convenience stores or fast-food outlets, which offer fewer healthy options (Walker et al., 2010; Beaulac et al., 2009). The importance of the food environment cannot be overstated, as physical access to affordable and healthy food options is essential for encouraging better dietary habits.

Consistency and Discrepancies Across Studies

Most of the studies reviewed consistently identified socioeconomic, psychological, and environmental factors as key determinants of healthy food consumption. The consistent findings across studies reinforce that income, education, and access to nutritious foods are potent predictors of dietary choices. For example, several studies concurred that individuals with higher levels of income and education have better access to healthy foods and are more knowledgeable about nutrition, which leads to healthier dietary habits (Darmon & Drewnowski, 2008; Kirkpatrick & Tarasuk, 2011). Likewise, the relationship between psychological factors, such as health consciousness, and dietary behaviour was generally well-supported across studies (Glanz et al., 1998; Povey et al., 2000).

However, some discrepancies emerged, particularly in the magnitude of the effect sizes. For instance, while all studies identified income as a barrier to healthy food consumption, the strength of this association varied. Some studies reported more potent effects of income than others, possibly due to differences in study design, population characteristics, or local food environments. Additionally, although many studies supported the influence of psychological factors, a few did not find significant associations between health consciousness and food consumption, particularly in populations where other barriers, such as food access, were more salient. This suggests that psychological factors may be more influential when basic access needs are met, while in environments where access is restricted, these factors may play a secondary role (Walker et al., 2010).

Regarding environmental factors, while most studies affirmed the importance of food accessibility, there was variability in how researchers defined and measured food deserts. Some studies used geographic distance to supermarkets as the sole measure of access, while others incorporated food affordability and quality into their definitions. This variation in definitions may explain the discrepancies in findings regarding how the food environment influences healthy eating behaviours.

Policy and Practical Implications

The findings from this review suggest several critical implications for policy and practice aimed at increasing healthy food consumption in the USA. First, addressing the socioeconomic barriers to healthy eating is paramount. Policy interventions could focus on making healthy foods more affordable, particularly for low-income populations. For example, increasing subsidies for fruits, vegetables, and other nutritious foods could lower prices and make them more accessible to economically disadvantaged groups (Moore & Roux, 2006). Additionally, expanding programs like the Supplemental Nutrition Assistance Program (SNAP) and ensuring that they are designed to encourage the purchase of healthy foods could help mitigate the financial barriers to healthy eating (Andreyeva et al., 2011).

Improving nutrition education is another critical area for intervention. Public health campaigns that promote the long-term health benefits of healthy eating, alongside practical information on how to prepare affordable and nutritious meals, could increase health consciousness and self-efficacy, particularly among low-income and less-educated populations (Worsley, 2002). These campaigns could be tailored to address specific psychological barriers, such as low confidence in cooking skills or a preference for processed foods, by offering cooking classes or providing accessible, affordable, and quick meal plans.

Environmental interventions are also essential. Policies that aim to reduce food deserts by incentivizing supermarkets and farmers' markets to operate in underserved areas could improve access to healthy foods. For example, offering tax breaks or other incentives to businesses that provide fresh and affordable food in low-income neighbourhoods may encourage more equitable food distribution (Walker et al., 2010). Additionally, policies regulating the marketing and availability of unhealthy foods in convenience stores and fast-food outlets could help shift dietary behaviours toward healthier choices, especially in communities with abundant unhealthy food options (Beaulac et al., 2009).

Limitations of the Review

While this review provides valuable insights into the factors affecting healthy food consumption, several limitations should be acknowledged. First, the studies had considerable heterogeneity regarding sample size, population characteristics, and methodologies. This variability makes it difficult to generalize the findings across all populations in the USA. For example, while some studies focused on urban populations, others looked at rural communities, which may face different barriers to healthy eating; studies with varying designs (e.g., cross-sectional, longitudinal, qualitative) also introduce heterogeneity in the findings.

Second, the review was limited by the quality of the included studies. Although steps were taken to assess the risk of bias and study quality, some studies may have had methodological flaws, such as self-reported dietary data, which are prone to recall bias and inaccuracies (Hebert et al., 1997). Furthermore, some studies lacked sufficient control for confounding variables, such as differences in physical activity or overall lifestyle, which could affect dietary behaviour independently of the factors studied.

Third, most studies included in the review were observational, limiting the ability to establish causal relationships. While associations between socioeconomic, psychological, and environmental factors and healthy food consumption were identified, it is difficult to determine whether these factors directly cause changes in dietary behaviour. Longitudinal or intervention studies would be needed to confirm causal links.

Finally, there may have been publication bias, as studies with significant findings are more likely to be published, while null or insignificant results may be underrepresented. This could lead to overestimating the effect of certain factors, such as income or health consciousness, on healthy food consumption (Rothstein et al., 2005).

This systematic review and meta-analysis examined the key factors influencing healthy food consumption in the USA, focusing on socioeconomic, psychological, and environmental determinants. The findings indicate that socioeconomic factors, particularly income and education, significantly impact dietary choices. Individuals from lower-income groups were found to be 28% less likely to consume healthy foods (pooled OR = 0.72; 95% CI: 0.65–0.80), mainly due to the higher costs of nutritious food, lack of time for meal preparation and limited access to nutrition education. These barriers suggest that targeted interventions, such as subsidies for healthy foods and expanded nutritional education, are necessary to improve dietary habits among disadvantaged populations. Psychological factors, including health consciousness and self-efficacy, significantly influenced healthy food consumption. Individuals with lower health consciousness were 38% less likely to consume healthy foods (pooled OR = 0.62; 95% CI: 0.55–0.70). This emphasizes the importance of increasing awareness of the long-term health benefits of a nutritious diet and enhancing confidence in one's ability to maintain healthy eating habits. The review also highlighted environmental barriers, such as food deserts, where individuals living in areas with poor access to healthy food were 43% less likely to consume nutritious options (pooled OR = 0.57; 95% CI: 0.50–0.65). Policy measures incentivizing supermarkets and farmers' markets to operate in underserved areas could help bridge this gap. In conclusion, improving healthy food consumption in the USA requires a multi-dimensional approach that addresses economic disparities, psychological drivers, and food accessibility. These findings offer valuable insights for policymakers and public health professionals seeking to create environments conducive to healthier eating habits across all socioeconomic groups.