The Psychology of Eating: From Healthy to Disordered Behavior

Obesity 169

the individual’s body weight. Therefore, exercise has long been recommended
as a weight loss method (see chapter 9). However, the number of calories
exercise burns up is relatively few compared to those in an average meal.
In addition, although exercise is recommended as a means to increase
metabolic rate, only intense and prolonged exercise appears to have a
beneficial effect.
In summary, population data illustrate a correlation between decreased
activity and increased obesity. Prospective data support this association and
highlight lower levels of activity as an important risk factor. Cross-sectional
data also indicate that the obese appear to exercise less than the nonobese.
However, whether inactivity is a cause or consequence of obesity remains
unresolved. It is possible that people who are obese take less exercise, due
to factors such as embarrassment, stigma, or discomfort when exercising.
Lack of exercise may play a part in the maintenance of obesity but may
not be the original cause. It is also possible that an unidentified third factor
may be creating this association. In addition, whether exercise has a role
in reducing food intake and promoting energy expenditure is also debat-
able. Therefore, the role of exercise in causing obesity remains unclear.
But exercise may benefit the obese in terms of promoting weight loss, main-
taining any weight losses, improving their health status, or making them
feel better about themselves (see chapter 9).

Eating behavior

In an alternative approach to understanding the causes of obesity, research
has examined eating behavior. Earlier, in chapter 3 and chapter 6, the dif-
ferent explanatory theories of eating behavior and dieting were outlined
with a focus on cognitions and learning and the impact of attempted food
restriction on food intake. It is possible that these can also help explain
obesity. Those who are obese may have different beliefs about food; they
could have been brought up in a family in which they were often exposed
to unhealthy food, or where unhealthy food was used as a reward and
restricted in ways that made food forbidden and, therefore, more desir-
able; or early weight gain may have resulted in dieting which, over time,
led to further weight gain and obesity.
Research specific to obesity has asked, “Are changes in food intake asso-
ciated with changes in obesity?” “Do the obese eat for different reasons than
the nonobese?” “Do the obese eat more than the nonobese?” and “How does
dieting influence obesity?”