Weight loss for teens: Family support effective. Family therapy, not so much.

By Nestor Lopez-Duran PhD

A family-based psychoeducational weight loss treatment for teens appears to be more effective than traditional family therapy.

Psychologists often work on the premise that any therapy is better than no therapy. Usually this tenet applies, in that most research shows that for most conditions therapy is better than no therapy. But unfortunately there are exceptions. Some interventions, in very specific conditions, may actually do more harm than good. It seems that short-term family systems therapy as part of a weight loss program for teenage girls may be one of such cases.

A team from the University of South Carolina conducted a controlled clinical trial of a family-based weight loss intervention program for teen girls. The authors were primarily interested in examining the effects of two family variables in weight loss: family nurturance (warmth) and family cohesion (closeness). These family factors are associated with a number of positive behavioral outcomes in teens, so it was hypothesized that interventions that help foster nurturance and cohesion would facilitate the effectiveness of weight loss programs.

In the study the authors randomly assigned 42 families with an overweight teenage girl to one out of three treatment conditions: 1) a family-based psychoeducational program, 2)a family-based psychoeducational program PLUS a multi-family therapy group, and 3) and a non-treatment (waiting list) condition. The psychoeducational program encouraged weight-loss behaviors and parental support but it did not include a specific caloric restriction goal, as the authors indicated that this is usually not effective with adolescents. The multi-family therapy program consisted of weekly 45 minute sessions of traditional group therapy during which families were able to address many issues, including the challenges they were encountering during the implementation of the psychoeducational program. Finally, the waiting list group simply waited until the end of the first phase of the study and then were given the opportunity to receive the treatment. These interventions lasted for 16 weeks.

The Results:
After 4 months, the average BMI of the participants of all three groups did not change significantly, and this index was practically identical between the groups. That is, the two treatment conditions were not more effective than the non-treatment group in reducing the body mass index.

However, a major difference between the groups was observed in energy intake. The girls in the psychoeducational group only displayed a significant reduction in energy intake. Instead, the girls in the family therapy plus psychoeducation displayed an increase in energy intake and this was comparable to the increase observed in the non-treatment group. Therefore, it seems that the psychoeducational intervention helped these girls eat less, but when family therapy was added, the benefits of the psychoeducational intervention vanished.

Concerning the effects of family nurturance and cohesion. The authors found that families that improved in family nurturance during the intervention also showed a significant reduction in energy intake. This suggests that family warmth and support helps adolescent girls lower their food intake.

Finally, family therapy led to higher levels of family conflict. The authors suggested that conflict issues may have arisen during therapy that were not fully addressed given the duration of the treatment. However, 4 months of therapy is within the norm for group therapy programs, thus it seems that this particular form of therapy, for this particular issue and population (weight loss in overweight but otherwise psychologically healthy teenage girls) is not effective in facilitating weight loss and may actually lead to increased family conflict. Please note however, that family systems therapy has been found effective for many conditions, including eating disorders (e.g., anorexia). This study ONLY assessed family therapy as part of a weight loss program in otherwise healthy girls.
Reference:Kitzman-Ulrich, H., Hampson, R., Wilson, D., Presnell, K., Brown, A., OBoyle, M. (2009). An Adolescent Weight-Loss Program Integrating Family Variables Reduces Energy Intake Journal of the American Dietetic Association, 109 (3), 491-496 DOI: 10.1016/j.jada.2008.11.029