The Psychology of Eating: From Healthy to Disordered Behavior

An Integrated Model of Diet 279

Obesity is another eating-related problem which does have clinically
significant consequences, and although it still only affects a minority its
incidence is on the increase. There is evidence for a strong genetic
basis for obesity, but inheritance is not the complete story. There is
also an important role for both diet and exercise. Although obesity is a
common problem and interventions have been designed by a range of
clinicians, the effectiveness of obesity treatments remain poor. In parti-
cular, although dieting can result in weight loss in the short term, weight
regain is common. While exercise may not be as effective as dieting at
promoting initial weight loss, it has greater overall benefits to health and
may be more predictive of long-term weight loss and maintenance. Drug
therapy and surgery may result in more success but can be accompanied
by unpleasant side effects. Success may also be predicted by the indi-
vidual’s beliefs about what obesity is. The problem of obesity exemplifies
how healthy eating is made difficult by the context in which food in
consumed.
Anorexia and bulimia are eating disorders at the far end of the spec-
trum. Although much rarer than weight concern and obesity, anorexia in
particular has more serious implications for mortality and morbidity.
Theories of what causes eating disorders highlight a role for genetics,
family relationships, the function of symptoms, the role of learning and
dysfunctional cognitions, conflicts arising from the modern world, and the
need for control. Treatment perspectives address these aspects of etiology
where possible. Eating disorders illustrate how attempts to eat healthily
can be sabotaged by a range of factors and how the meanings associated
with food and size impinge on an individual’s eating behavior in the
extreme.
From this analysis, therefore, diet can be understood on a continuum
from healthy to disordered eating which increasingly places food intake within
its social context. Common themes emerge across these different aspects
of diet-related research. These will now be considered.

Common Themes Across the Literature on Eating Behavior

Many themes have emerged throughout the literature on diet which are
common across disciplines, areas of study, and the aspect of food intake
being considered. These are described below.