Ultra-Processed Food Intake Linked to Higher Risk of Binge Eating in Adults Living with Obesity

Key Takeaways: 

• Higher consumption of ultra-processed foods was associated with increased symptoms of binge eating, bulimia-related behaviours, and emotional or uncontrolled eating in adults living with obesity.
  
• Individuals consuming the greatest proportion of ultra-processed foods had poorer overall diet quality and significantly lower protein intake.
  
• The findings suggest that addressing eating behaviour patterns alongside dietary composition may be important when supporting people living with obesity.
  
  
  

Rising consumption of ultra-processed foods during nutritional transition

A cross-sectional study published in Archives of Endocrinology and Metabolism has explored the relationship between ultra-processed food (UPF) intake and eating behaviour among adults living with obesity in São Paulo, Brazil.

The research was conducted against the backdrop of a broader nutritional transition that has been occurring in many developing countries. Economic development, demographic changes, cultural shifts, and evolving food systems have led to major transformations in dietary patterns.

While these changes have contributed to reductions in malnutrition and infectious diseases, they have also been accompanied by a marked increase in noncommunicable diseases such as obesity. A key driver of this shift has been the growing consumption of highly processed foods that are rich in fat, sugar, and refined ingredients.

Previous research has linked high consumption of ultra-processed foods to a range of adverse health outcomes, including obesity, overweight, type 2 diabetes, metabolic syndrome, cardiovascular and cerebrovascular disease, anxiety, depression, and increased all-cause mortality.

There is also emerging evidence that ultra-processed foods may influence eating behaviour itself. Some studies suggest that these foods may affect neurobiological and endocrine pathways that regulate appetite, potentially encouraging compulsive overeating.

Disordered eating patterns are also known to occur among individuals living with obesity. These patterns can complicate treatment and may reduce the effectiveness of weight management interventions. Understanding how ultra-processed food consumption interacts with eating behaviour is therefore clinically important.

Study design and participant characteristics

To explore this relationship, researchers recruited adults aged 18 to 59 years living with obesity, defined as a body mass index (BMI) of 30 kg/m² or higher. Participants were recruited both through a clinical obesity treatment service and via social media in São Paulo.

Several exclusion criteria were applied to minimise confounding factors. Individuals were excluded if they were pregnant or had diagnosed eating disorders, cardiac disease, renal disease, obesity caused by genetic disorders, or if they were taking antiepileptic medications or corticosteroids. People who smoked, misused alcohol, or were currently receiving pharmacological treatment for weight loss were also excluded.

Dietary intake was assessed using three non-consecutive 24-hour dietary recalls, including one weekend day. Researchers used the multiple-pass method, a structured interview approach designed to improve the accuracy of dietary reporting.

Foods reported in the recalls were categorised using the NOVA classification system, which groups foods according to the degree of industrial processing. Diet quality was assessed using the Diet Quality Index associated with the Digital Food Guide.

Eating behaviour was evaluated using validated self-administered online questionnaires:

• BITE (Bulimic Investigatory Test Edinburgh) – measuring symptoms and severity of bulimia and binge eating
  
• TFEQ-21 (Three-Factor Eating Questionnaire) – assessing cognitive restraint, emotional eating, and uncontrolled eating
  
• DEBQ (Dutch Eating Behaviour Questionnaire) – evaluating external eating, emotional eating, and restrained eating
  

Associations between ultra-processed food intake and eating behaviours were analysed using generalised linear models.

Prevalence of unusual eating behaviours

A total of 77 adults took part in the study. Of these participants, 78 percent were female.

The mean age of the group was 36 years, and the average BMI was 39.14 kg/m², corresponding to class II obesity.

Participants were divided into three groups based on the proportion of calories derived from ultra-processed foods:

• First tertile – less than 24.1 percent of calories from UPFs
  
• Second tertile – 24.1 percent to 35.4 percent
  
• Third tertile – more than 35.4 percent
  

Only around one quarter of participants displayed what researchers classified as normal eating behaviour.

In contrast:

• Approximately 52 percent exhibited unusual eating behaviour
  
• 23.4 percent reported binge eating
  

Symptoms consistent with unusual eating behaviours were observed across all tertiles of ultra-processed food consumption. However, participants in the highest UPF tertile showed significantly higher symptom scores on the BITE questionnaire compared with those in the lowest tertile.

Despite this difference in symptom scores, severity scores did not significantly differ between groups.

Overall, 40.3 percent of participants had clinically significant symptoms, while 13 percent were classified as having severe symptoms.

Eating style patterns associated with UPF intake

The study also examined several different eating style patterns.

Using the DEBQ questionnaire, researchers found that:

• 37.8 percent of participants had elevated external eating scores
  
• 36.5 percent had elevated emotional eating scores
  
• 25.7 percent had elevated restrained eating scores
  

Results from the TFEQ-21 questionnaire revealed:

• 52 percent had higher emotional eating
  
• 29.3 percent demonstrated increased cognitive restraint
  
• 18.7 percent showed higher uncontrolled eating
  

Higher intake of ultra-processed foods was positively associated with several problematic eating behaviours.

These included:

• Binge eating and bulimia-related symptoms measured by BITE
  
• Emotional eating
  
• External eating
  
• Uncontrolled eating
  

Together, these results suggest that people consuming larger amounts of ultra-processed foods were more likely to display eating behaviours characterised by reduced self-regulation and greater responsiveness to emotional or environmental triggers.

Diet quality and macronutrient intake

Across the overall study population, diet quality was classified as intermediate.

Participants in the highest ultra-processed food tertile had significantly lower diet quality scores than those in the lower tertiles.

Clear dietary differences were also observed between groups.

Participants in the lowest tertile consumed a higher proportion of unprocessed or minimally processed foods, whereas those in the highest tertile consumed more ultra-processed foods.

Interestingly, individuals in the first and second tertiles reported greater intake of processed culinary ingredients, such as oils or sugars used in cooking, compared with those in the third tertile.

The average macronutrient distribution across the entire sample was:

• 20 percent protein
  
• 48 percent carbohydrates
  
• 32 percent lipids
  

Participants in the highest UPF tertile had significantly lower protein intake than those in the other groups. Carbohydrate and lipid intake did not differ significantly between tertiles.

Median total daily caloric intake across the sample was 1,661 kcal. However, participants in the highest UPF tertile reported higher caloric intake than those in the second tertile.

Researchers suggested that lower protein intake associated with higher UPF consumption may influence satiety and appetite regulation, potentially contributing to overeating.

Clinical implications and study limitations

Overall, the study found that more than half of adults living with obesity exhibited unusual eating behaviours.

Higher intake of ultra-processed foods was associated with:

• Binge eating
  
• Bulimia-related symptoms
  
• Emotional eating
  
• External eating
  
• Uncontrolled eating
  

In addition, greater consumption of ultra-processed foods was linked to poorer diet quality and reduced protein intake.

These findings suggest that obesity treatment strategies may benefit from incorporating both dietary assessment and evaluation of eating behaviour patterns. Addressing behavioural drivers alongside nutritional composition could potentially improve weight management outcomes.

However, the authors emphasised several important limitations.

Because the study used a cross-sectional design, it cannot establish cause-and-effect relationships. The research was also conducted within a single clinical population in one urban centre, which may limit the generalisability of the findings.

In addition, dietary recalls and questionnaires were self-reported, which may introduce recall bias or social desirability bias. The relatively small sample size and predominantly female participant group may also affect the applicability of the results to broader populations.

Nevertheless, the study highlights the importance of considering ultra-processed food consumption within a wider behavioural and nutritional context when addressing obesity and supporting individuals in weight management.