A new clinical study links the consumption of ultra-processed foods to disturbed eating patterns and poor diet quality in obese adults, highlighting potential targets for improving nutritional interventions.
study: Increased intake of ultra-processed foods is associated with eating disorder symptoms and poorer diet quality in obese adults. Image credit: Inna Tarnavska / Shutterstock
In a recent cross-sectional study published in Endocrinology and Metabolism Archivesresearchers investigated ultra-processed foods (UPF) Relationship between intake and eating behavior of obese adults in São Paulo, Brazil.
Changes in nutrition and consumption of ultra-processed foods
Nutritional transitions are increasingly observed in developing countries due to demographic, economic, cultural, and social changes. This change is characterized by a decline in malnutrition and infectious diseases, with a parallel increase in non-communicable diseases such as obesity. These changes are primarily driven by increased consumption of industrially processed foods rich in fat and sugar.
High intakes of ultra-processed foods (UPFs) are associated with increased rates of obesity, overweight, type 2 diabetes, metabolic syndrome, cardiovascular and cerebrovascular disease, anxiety, depression, and all-cause mortality. Emerging evidence suggests that UPF may alter eating behavior and promote compulsive overeating by affecting neurobiological and endocrine pathways involved in appetite regulation.
Eating disorders and disturbed eating patterns can occur in obese people and can negatively impact the effectiveness of weight management interventions. Therefore, understanding how UPF consumption relates to eating behavior is clinically important.
Study design and participant characteristics
The study included adults aged 18 to 59 with obesity, defined as body mass index (BMI).BMI) ≥ 30 kg/m², via Clinical Bariatric Services of São Paulo and social media. Exclusion criteria included pregnancy, diagnosed eating disorders, heart or kidney disease, obesity secondary to genetic disorders, use of antiepileptic drugs or corticosteroids, smoking, alcohol abuse, and ongoing drug reduction therapy.
Dietary intake was assessed using the average of three nonconsecutive 24-h dietary recalls performed in a multipass method, including one weekend day. Foods were classified using the NOVA classification system to determine the degree of industrial processing. Diet quality was assessed using a diet quality index linked to a digital food guide.
Eating behavior was assessed through a validated self-administered online questionnaire.
- biteto measure symptoms and severity of bulimia and bulimia.
- TFEQ-21assessment of cognitive inhibition, emotional eating, and uncontrolled eating.
- DebukuAssess external, emotional, and restrained eating
The association between UPF intake and feeding behavior was analyzed using generalized linear models.
Prevalence of abnormal eating behavior
A total of 77 adults participated, of whom 78% were women. The mean age was 36 years, and the mean BMI was 39.14 kg/m², consistent with class II obesity on average.
Participants were divided into tertiles based on the percentage of calories derived from UPF.
- First tertile: < 24.1% of calories from UPF
- Second tertile: 24.1%-35.4%
- Third tertile: > 35.4%
Only about a quarter of the participants showed normal eating behavior. Approximately 52% exhibited abnormal eating behavior and 23.4% reported bulimia. Symptoms consistent with an abnormal diet were observed across all tertiles. The highest UPF tertile had significantly higher BITE symptom subscale scores compared to the lowest tertile, but severity scores were not significantly different between groups.
Overall, 40.3% of participants had clinically significant symptoms and 13% had severe symptoms.
Eating style patterns and UPF intake
Regarding eating style, 37.8% of participants had increased external eating scores, 36.5% had increased emotional eating scores, and 25.7% had increased restrained eating scores. On the TFEQ-21, 52% showed increased emotional eating, 29.3% showed increased cognitive inhibition, and 18.7% showed increased uncontrolled eating.
UPF intake was positively correlated with binge eating and binge eating symptoms as measured by BITE, emotional eating, eating out, and uncontrolled eating. These findings suggest that higher intakes of ultra-processed foods are associated with eating behaviors characterized by decreased self-regulation and increased reactivity to emotional and environmental cues.
Diet quality and macronutrient intake
Diet quality was classified as intermediate within the first and second tertiles of UPF across the sample. Individuals in the highest UPF tertile had significantly lower diet quality scores than individuals in the lower tertiles.
The first tertile consumed more unprocessed or minimally processed foods, and the third tertile consumed a higher proportion of UPF. The first and second tertiles reported higher intakes of processed culinary ingredients compared to the third tertile.
The average distribution of macronutrients was 20% protein, 48% carbohydrate, and 32% fat. The third tertile had significantly lower protein intake than the other tertiles, but carbohydrate and fat intakes were not significantly different between groups. The median total caloric intake was 1,661 kcal, with higher caloric intake observed in the third tertile compared to the second.
High UPF intake is associated with poor diet quality and reduced protein intake, which can affect satiety and appetite regulation.
Clinical significance and study limitations
The study found that more than half of obese adults exhibited abnormal eating behaviors. Increased UPF intake was associated with bulimia, bulimia-related symptoms, emotional eating, eating out, and uncontrolled eating. Increased UPF intake was also correlated with poorer diet quality and decreased protein intake.
These findings suggest that obesity treatment strategies should incorporate assessment of aspects of diet quality and eating behavior that may predispose individuals to unhealthy food choices. Addressing behavioral factors along with dietary composition may improve weight management outcomes.
Because this is a cross-sectional study conducted in a clinical sample from a single urban center, causality cannot be established. Self-reported dietary recalls and questionnaires may introduce recall and social desirability bias. The small sample size and predominantly female composition may further limit generalizability.
Overall, the results highlight the need to consider ultra-processed food intake within a broader behavioral and nutritional framework for obesity management, while recognizing the observational nature of the findings.