Unhealthy Food and Psychological Stress: The Association between Ultra-Processed Food Consumption and Perceived Stress in Working-Class Young Adults

Abstract

Background: Ultra-processed foods are industrial formulations made from food extracts or constituents with little or no intact food and often containing additives that confer hyper-palatability. The consumption of these products increases the risk of chronic non-communicable diseases. Stressed people may engage in unhealthy eating as a way to cope. This study aimed to verify whether ultra-processed food consumption was associated with perceived stress levels in industrial and retail workers from Vitoria da Conquista, Brazil. Methods: This was a cross-sectional study carried out between July 2017 and August 2018. During the study period, 1270 participants completed a survey administered by an interviewer. Stress levels were assessed using the Perceived Stress Scale. Information regarding weekly ultra-processed food consumption was collected. Ultra-processed foods were classified into four groups: sugary drinks; sugary foods; fast foods; and canned foods, frozen foods, or processed meat. The Student’s t-test or one-way analysis of variance was used to assess the differences in stress levels and ultra-processed food consumption. Ordinal regression was used to determine the association between the degrees of stress and ultra-processed food consumption levels. Results: Factors such as a young age, being unmarried, smoking, high-risk alcohol consumption, negative health perception, and high perceived stress level indicated higher rates of ultra-processed food consumption. Ordinal regression analysis showed that high stress levels were associated with increased odds of higher ultra-processed food consumption (odds ratio: 1.94; 95% CI: 1.54–2.45). Conclusions: These findings could help identify appropriate target areas for interventions aimed at mental health promotion and healthier food consumption.

Ultra-Processed Food Consumption and Mental Health: A Systematic Review and Meta-Analysis of Observational Studies

“…Although the third study reported a beta-coefficient, it was not possible to estimate the confidence interval given an exact p-value or measure of variance were not reported [17]. Similarly, four studies [20,[25][26][27] did not report p-values. We estimated these by using the confidence intervals as per the methods proposed by [47].…”

“…Eleven studies modelled ultra-processed food consumption as the exposure variable and mental disorder parameters as the outcome [17][18][19]21,[23][24][25][26]30,48,50], with the remaining six modelling associations in the opposite direction [20,22,[27][28][29]31].…”

“…Of the six studies that modelled mental disorder parameters as the exposure, one was coded continuously [22], with the remaining five coding these categorically (dichotomous [20,28,29], tertiles [27] and between-group comparison of patients with anorexia nervosa, bulimia nervosa and binge eating disorder [31]).…”

“…Eleven studies reported average ultra-processed food consumption, and various methods were used, with some studies using more than one approach. These methods included energy per day [19,24,28,30,48,50]; grams per day [28,48,49]; the proportion of total food intake [23,31]; mean frequency of consumption score [17]; servings per day [50]; intake in the past week [27]; and grams per kilocalories [18] (see Table S2 for a detailed summary of the ultra-processed food exposure and outcome variables and average ultraprocessed food consumption). However, the average intake of ultra-processed food was most commonly expressed as a percentage of total energy, which had a mean value of 32% and ranged from 17.3% to 54.9% [19,28,48,50].…”

“…However, the meta-analysis assessing associations of ultra-processed food consumption with mental disorders was limited only to depression and by the number of studies available for inclusion at the time of publication (n = 2). Several additional studies have since been published assessing the link between ultra-processed food consumption and depression as well as other mental disorders [17][18][19][20][21][22][23][24][25][26][27][28][29][30][31]. The need for an updated review is further exacerbated by the fact that ultra-processed foods have become increasingly ubiquitous for many food systems globally [13], thus understanding any relationship with mental disorders is critical for understanding the health implications of this trend.…”