In plain language
Acceptance and Commitment Therapy and related approaches help people manage their weight by building psychological flexibility—the ability to stay present, experience difficult thoughts and feelings openly, and keep acting on one's values. Researchers usually treat flexibility as a single, global quality that a person has more or less of. But flexibility actually comprises several components, such as acceptance, defusion (not getting entangled in thoughts), awareness, values, and committed action. This study asked whether people in different weight categories struggle with different components—a question with direct implications for how weight interventions should be designed.
The team assessed weight status and a broad range of flexibility components in a nationally representative sample of 7,884 American adults (average age about 48), using a planned missing data design that allowed many measures to be included without overburdening participants. They then compared the flexibility profiles of underweight, healthy-weight, overweight, obese, and severely obese men and women.
The profiles were strikingly different. Underweight men showed a “defensive but active” pattern: high avoidance and high fusion with thoughts, yet also high hope and willingness to experience distress in pursuit of goals. Overweight and obese participants showed no general elevation in inflexibility—in fact, overweight men appeared somewhat more flexible than other men. Only severely obese participants showed broad inflexibility, and even then the pattern differed for men and women. The authors conclude that psychological flexibility should not be treated as one dimension, and that interventions should target the specific components relevant to specific groups.
Key findings
- In a nationally representative US sample (N = 7,884; 3,748 men, 4,136 women), different weight and gender groups showed distinctly different configurations of psychological inflexibility rather than uniform differences on a single dimension.
- Underweight men showed a “defensive but active” profile: high avoidance across multiple dimensions and high cognitive fusion, combined with high hope and high willingness to experience distress when pursuing goals.
- Overweight and obese participants did not show elevated inflexibility overall; there was some evidence that overweight men (but not obese or severely obese men) were more psychologically flexible than other men.
- Severely obese participants showed elevated inflexibility across multiple indices, but the specific pattern differed between men and women.
- The lack of parallel profiles across BMI categories challenges the common practice of treating psychological flexibility as a unitary construct.
- The findings suggest weight interventions could be tailored to the specific flexibility components most relevant to a given weight and gender group.
How to cite
APA
Ciarrochi, J., Sahdra, B., Marshall, S., Parker, P., & Horwath, C. (2014). Psychological flexibility is not a single dimension: The distinctive flexibility profiles of underweight, overweight, and obese people. Journal of Contextual Behavioral Science, 3, 236–247. https://doi.org/10.1016/j.jcbs.2014.07.002
BibTeX
@article{ciarrochi2014psychological,
author = {Ciarrochi, Joseph and Sahdra, Baljinder and Marshall, Sarah and Parker, Philip and Horwath, Caroline},
title = {Psychological flexibility is not a single dimension: The distinctive flexibility profiles of underweight, overweight, and obese people},
journal = {Journal of Contextual Behavioral Science},
year = {2014},
volume = {3},
pages = {236--247},
doi = {10.1016/j.jcbs.2014.07.002}
}
Related work
- All publications by Joseph Ciarrochi (searchable, with free PDFs)
- Process-Based Therapy & Idionomic Analysis
Author: Joseph Ciarrochi (ORCID 0000-0003-0471-8100). Free copy hosted with permission for scholarly use. Please cite the published version via the DOI above.