Impact of non-diet approaches on attitudes, behaviors, and health outcomes: a systematic review

Objective: To determine the overall effect of non-diet, weight-neutral interventions on factors such as weight, biochemical measures, food and activity behavior, body image, and mental health.

Design: Systematic review of intervention literature.

Setting: Group classes in community and worksite settings (14 studies), and individual counseling (1) and online education (1) in college settings.

Participants: Eighteen research articles (representing 16 studies) evaluating non-diet interventions using quasi-experimental and randomized study designs with either a comparison or control group.

Main outcome measures: Anthropometric, physiological, psychological, and dietary intake.

Analysis: Systematic search of 168 articles and review of 18 articles meeting inclusionary criteria.

Results: Non-diet interventions resulted in statistically significant improvements in disordered eating patterns, self-esteem, and depression. None of the interventions resulted in significant weight gain or worsening of blood pressure, blood glucose, or cholesterol, and in 2 studies biochemical measures improved significantly compared with the control or diet group. Primary limitations were inconsistent definitions of non-diet approaches and the use of different assessment instruments for measuring outcomes.

Conclusions and implications: Because of the long-term ineffectiveness of weight-focused interventions, the psychological improvements seen in weight-neutral, non-diet interventions warrant further investigation.