Researchers studying food behavior have identified a crucial element in overeating.

Disinhibited eating is a pattern of behavior that involves eating too quickly and a repeated lack of success when dieting. Many studies show it is linked to higher body mass index (BMI), and is a strong risk factor for overweight and obesity.

This tendency to overeat can occur in a variety of circumstances, such as when an individual is presented with an array of palatable foods or is under emotional distress.

Now, PhD student Laura L. Wilkinson and her team at the University of Bristol, U.K., have investigated the psychological origins of disinhibited eating. The topic has “received scant attention,” they write in the International Journal of Obesity.

However, “relative to other psychological variables, disinhibited eating is the single best predictor of BMI,” they report, “and this relationship is evident in groups with different socioeconomic status, weight history and dieting status. Importantly, disinhibited eating predicts future weight gain, suggesting that it has a causal role in overweight and obesity.”

The team decided to focus on adult attachment styles as a potential explanation for disinhibited eating. A person’s attachment style reflects the quality of bonding in early life, and is believed to remain stable throughout adulthood. “It describes a representational model of personal relationships and reflects early-life interactions with primary caregivers,” write the authors.

Four styles of attachment have been identified in adults: secure, anxious-preoccupied, dismissive-avoidant, and fearful-avoidant. Previously, the three insecure attachment styles have been linked to other manifestations of disinhibited behavior, such as smoking, alcohol consumption, substance abuse and sexual promiscuity.

This has been explained as differences in the need for external emotional regulation, that is, a behavior or substance that alters a person’s emotional state by promoting calm, distraction or excitement. In other words, individuals who are more anxious tend to rely on external factors for emotional control.

The researchers looked at whether attachment style influences the tendency to engage in disinhibited eating. They recruited 200 adults with a mean age of 22 years, whose BMIs ranged from 17 to 41. Measures of disinhibition and attachment style were taken using the Three-Factor Eating Questionnaire (TFEQ) and the Experiences in Close Relationships (ECR) questionnaire.

Results showed that “attachment anxiety” was significantly linked to disinhibited eating and to BMI. Further analysis indicated that attachment anxiety influences BMI via its relationship with disinhibited eating.

Insecurely attached individuals with “attachment avoidance,” on the other hand, did not show a tendency toward disinhibited eating or higher BMI.

“These findings are consistent with other studies, showing an association between attachment orientation and other disinhibited behaviors, including alcohol and substance abuse,” say the authors. “Our interpretation is that disinhibited eaters engage in external affect regulation. In doing so, they seek to mitigate the anxiety associated with poor interpersonal attachments.”

In summary, a tendency to seek comfort through overeating leads to a positive energy balance and, over time, an increase in BMI. The experts point out that significant life events seem to coincide with shifts in BMI.

“For example, rapid weight gain is associated with leaving the parental home and starting university (the Freshman 15 phenomenon), and similar shifts in BMI are observed in inmates who have recently entered prison,” they write. “Anxiously attached individuals may be more sensitive to these events.”

They suggest that attachment anxiety is used as a predictor of weight gain in future research. “The role of childhood attachment would merit scrutiny in this context,” Wilkinson concludes.

This unique study was partly inspired by a review from the University of Leeds, U.K., on the evidence linking disinhibition to weight regulation, food choice and eating disorders. It found, “Disinhibition is an important eating behavior trait. It is associated not only with a higher BMI and obesity, but also with mediating variables, such as less healthful food choices, which contribute to overweight/obesity and poorer health.”

Professor John Blundell and colleagues also report that disinhibition can predict poorer success at weight loss and greater weight regain, and “is associated with lower self-esteem, low physical activity and poor psychological health.”

“Disinhibition therefore emerges as an important and dynamic trait, with influences that go beyond eating behavior and incorporate other behaviors which contribute to weight regulation and obesity,” they state.

“Habitual disinhibition may be the most important correlate of weight gain leading to obesity simply because of the high number of daily overeating opportunities it provides in the typical western food environment,” adds Dr. Donald W. Reynolds of the University of Arkansas.

He calls for studies to test the effectiveness of lifestyle modification and other treatment programs to reduce habitual disinhibition in an attempt to prevent weight gain.

References

Wilkinson, L. L. et al. Attachment anxiety, disinhibited eating, and body mass index in adulthood. International Journal of Obesity, published online March 30, 2010.

Bryant, E. J., King, N. A. and Blundell, J. E. Disinhibition: its effects on appetite and weight regulation. Obesity Reviews, Vol. 9, September 2008, pp. 409-19.

Hays, N. P. and Roberts, S. B. Aspects of eating behaviors “disinhibition” and “restraint” are related to weight gain and BMI in women. Obesity, Vol. 16, January 2008, pp. 52-8.

By Jane Collingwood