Anorexia nervosa and bulimia nervosa often are chronic eating disorders
associated with high comorbidity ().
Bulimia is more frequent than anorexia, with a prevalence of 90
to 95% among females ().
Although the prevalence of these disorders in the general population
usually is quite lower, an increase in the number of new cases has
been observed in men and women in all age groups. According to several
authors, the prevalence of these eating disorders (between 1 and
41%) has remarkably increased in the last few years ().
Anorexia nervosa, first described in 1667 (),
is a disease that leads to inanition with excessive self-inflicted
weight loss and with great physical and psychological distress.
Due to a distorted body image, individuals with anorexia nervosa
do not see themselves as thin, and therefore continue to restrict
their diet in a methodical way ().
Prepubertal patients may show delayed sexual maturation, delayed
physical development, growth retardation, and may not achieve their
target height. Anorexia nervosa has serious complications that result
from malnutrition, such as cardiovascular involvement, dehydration,
electrolytic disorders, gastrointestinal motility disorders, infertility,
hypothermia, and other signs of hypometabolism ().
Fisher reports that the presence of amenorrhea is an important characteristic
of anorexia nervosa, being associated with a combination of factors
such as hypothalamic dysfunction, stress, excessive exercises, and
weight and fat loss ().
Differently from anorexia, bulimia nervosa does not result in a
greatly depleted nutritional status. Bulimic patients often maintain
a near-normal weight or sometimes are slightly overweight, alternating
between bouts of hyperphagia and self-induced vomiting ().
The distortion of body image usually is less pronounced than that
observed in anorexia nervosa ().
The major complications of bulimia are electrolytic disorders, irritation,
gastroesophageal bleeding, intestinal disorders, erosion of the
dental enamel, and enlarged parotid glands. Resting bradycardia,
hypotension, and reduced metabolic rate are observed in some bulimic
patients, possibly indicating reduced activity of the sympathetic
nervous system and of the thyroid axis ().
Albeit yet unknown, the etiology of eating disorders is provably
associated with social, psychological, and biological factors ().
The fact that our culture venerates women with a slim body is related
to an increase in the occurrence of such disorders. Even though
cultural factors, especially the drive for thinness, are extremely
important, one should not forget that anorexia was first described
at a time in which the stereotype of female beauty used to be a
far cry from today's slim standards.
There are several psychological hypotheses that attempt to explain
inanition as an etiologic factor of these eating disorders. There
appears to be a consensus between these theories that eating disorders
act as a form of psychological deterrent by interrupting the physical
development of these adolescents, taking them to the prepubertal
With regard to genetic factors, several studies suggest that females
who have anorexic relatives have a greater propensity for anorexia.
According to the literature review conducted by Woodside, based
on twin studies, the inheritability of anorexia and bulimia corresponds
to 75 to 80% and 45 to 55%, respectively ().
Some studies suggest cross-transmission of these disorders, with
predominance of environmental factors in bulimia and genetic factors
in anorexia ().
The existence of an underlying hypothalamic dysfunction as the key
to the symptoms of eating disorders seems unarguable. On the other
hand, controversy still exists over whether this dysfunction is
primary or secondary, and if secondary, whether it results from
a nutritional deficit or emotional one, or from both ().
According to most authors, eating disorders are more prevalent in
industrialized countries, but several studies show that these disorders
constitute a public health problem in developing countries as well
The aim of the present study is to investigate the eating behavior
of children and adolescents, as well as to determine the prevalence
of eating disorders, not only of anorexia and bulimia, but also
of clinically relevant eating disorders, since there is a paucity
of studies in the Brazilian literature on this issue with this age
Students regularly enrolled in public schools of five municipalities
of the state of Minas Gerais, Brazil, were interviewed. The selected
municipalities/districts Dionísio, Inhaúma, Bom Jesus,
Nossa Senhora do Carmo and Ipoema are small-sized, with a population
between 3,000 and 5,000 inhabitants. Lectures were given in order
to explain the aims of the study; the students were invited to participate
in the study, and all of them accepted. The study included all students,
aged between 7 and 19 years old, enrolled in the public schools
of these towns (a total of 1,921 students). Students younger than
seven years old and older than 19, or those who were enrolled in
private schools, were not included. A loss of approximately 6% occurred,
which corresponds to those students who did not complete all the
tests. The final sample consisted of 1,807 students, 887 males and
The data were collected by fifth-year undergraduate students of
the School of Medicine of Minas Gerais between March 1998 and November
1998. Training sessions were held in order to prepare the researchers
for the application of the tests, with the aim of obtaining greater
homogeneity and resolving possible doubts. As self-rating scales
were used, the researchers were very careful not to induce the answers.
The following scales were used:
Eating Attitudes Test (EAT): developed by Garner & Garfinkel
initially as a diagnostic test for anorexia nervosa, but nowadays
used to detect eating disorders in general. The results obtained
showed that this test was not appropriate as a diagnostic tool,
but that it was good at detecting clinical cases in high-risk populations
and identifying individuals with an abnormal preoccupation with
their diet and weight. Of the original 40 items in the scale, the
authors decided to leave out 14, as they were considered to be redundant
and did not increase predictive power. The new scale, EAT-26, is
simpler and more economic, being highly correlated with the original
scale. A cutoff point of 20 was used.
Bulimic Investigatory Test Edinburgh (BITE): developed by
Henderson and Freeman ()
to detect bulimic episodes and the factors related to cognition
and behavior of bulimic individuals. This test may be used as an
epidemiological tool for the identification of subclinical cases
of bulimia and to monitor the outcome of patients and determine
their response to the treatment used. The BITE is divided into two
subscales: symptoms and severity.
- Symptom Subscale: Assessment of symptoms, eating behavior, and
diet; those with a score between 10 and 19 are considered to have
a somewhat unusual eating behavior and not to meet all the criteria
for the diagnosis of bulimia; those with a score higher than 19
show a high level of eating disorder, with the presence of bulimic
episodes, and high risks for bulimia nervosa.
- Severity Subscale: Assessment of the severity of eating disorders
based on their frequency; those with a score equal to or greater
than 5 show significant severity, and those with a score greater
than 9 have a high level of severity.
Body Image Test ():
individuals are shown several images of bodies that range in size
from extremely thin to obese. They are asked to choose the image
that best resembles their own body. After that, they are asked to
indicate which body image they would like to have. The discrepancy
between the two images shows how dissatisfied individuals are with
their bodies. The body image test used herein consists of five images.
In addition to choosing from the five images, the students could
choose an imaginary image, which gives a total of nine options.
The collected data were coded and imported into a statistical program
(EpiInfo 6.04). The basic statistical analysis and interpretation
were made using the same program.
The questionnaire did not contain any information that allowed identifying
the students. Participants gave their verbal consent and the schools
also authorized the study.
Among 1,807 students, 887 (49.1%) were male and 920 (50.9%) were
female, with an age range between 7 and 19 years old (mean age of
12.7±2.5 years). The distribution of the final sample among
the towns was as follows: Ipoema: 494 students (27.3%), Bom Jesus:
488 students (27%), Dionísio: 347 students (19.2%), Nossa
Senhora do Carmo: 263 students (14.6%), and Inhaúma: 215
As to the Eating Attitudes Test (EAT), 241 students (13.3%) had
a score equal to or greater than 20, that is, these students probably
have subclinical eating disorders. There was a female predominance
(p = 0.003) (Table1). Of these 241 students, only 43 (17.8%) showed
purging behaviors, indicating that such behaviors are significantly
more frequent (p = 0.000) in possible cases of bulimia nervosa (74%).
Table 1 -
Prevalence of students according to EAT-26
and BITE scores
The BITE revealed 19 students (1.1%) with a score equal to or
greater than 25, which corresponds to a possible diagnosis of bulimia;
seven (36.8%) of these students were male and 12 (63.2%) were female,
and all of them were older than 10 years. According to the symptom
subscale, 296 students (16.4%) had an average score (10 to 19),
showing a somewhat unusual eating behavior, and 10 students had
a high score (above 19), which indicates a probable diagnosis of
bulimia nervosa. There was a nonsignificant female predominance
both in the average score (p = 0.06) and high score (p = 0.79).
According to the severity subscale, 188 students (11.8%) reached
the cutoff point ( > 5), with basically no gender predominance
We found 1,059 students (59%) dissatisfied with their body images,
of whom 511 (48%) would like to be thinner and 548 (52%) would like
to be fatter. Among the students who would like to be thinner, 69%
were female and 31% were male (p = 0.000). Among those who would
like to be fatter, there was a significant male predominance (p
= 0.000). Also, we found 731 students (40%) who usually went on
some kind of diet, with a significant female predominance (p = 0.000).
Of these 731 students, only 118 (16%) went on a diet regularly,
while the remaining ones did so sporadically. Some people engage
in physical activity to lose weight. In our sample, 1,014 students
(56%) did exercises in order to lose weight, with a remarkable female
predominance (p = 0.000). Around 12% of the students had bulimic
episodes, and once again, there was a female predominance (p = 0.003).
Purging was used by 10% of the students (Table 2).
Table 2 -
Prevalence of students according to the
The present study showed a prevalence rate similar to that reported
by other countries, according to EAT and BITE scales. The prevalence
rate of the BITE scale is approximately 1 to 1.54 (22.27) in most
studies; in our study, the prevalence rate was 1.1%. The same occurs
with the EAT scales, whose prevalence is 6 to 13% ()
according to several studies; in our study, we found a rate of 13.3%.
Although eating disorders were significantly more frequent among
women, we found a high prevalence among males, showing that these
disorders have actually increased among men in the last few years
The abuse of laxatives, self-induced vomiting, pills, and diuretics
was quite common among students with a possible diagnosis of bulimia;
self-induced vomiting was the most widely used method, observed
in 73.34% (11 students) of the students with a possible diagnosis
of bulimia nervosa. Among the students at high risk for anorexia,
only 13% showed some purging behaviors. This is consistent with
the results of clinical trials, which indicate that such behaviors
are much more frequent in cases of bulimia nervosa.
As far as age is concerned, the peak prevalence among students with
a high score for eating disorders occurred in the 11-16 age group,
early adolescence and at the beginning of the mean (),
which is in agreement with other studies that report a higher prevalence
of these disorders in adolescents ().
The present study is one of the first publications about eating
disorders involving Brazilian children and adolescents, and was
carried out with communities in the rural area of the state of Minas
Gerais, a lower prevalence rate was expected because we believed
that regional sociocultural factors would be more preserved, acting
as a possible protective mechanism due to the increased family and
social interaction. However, we found rates that were as high as
those reported by other studies, contradicting the findings of some
studies, as the one conducted by Hoek (),
which advocate that the prevalence of these disorders may vary with
the level of urbanization of the studied region. The prevalence
rates are lower in underdeveloped regions, especially that of bulimia.
Nowadays, the increase of globalization may have a negative impact
on the population's eating habits and consequently increase the
incidence of eating disorders.
We thank the following undergraduate students of the School of Medicine
of Minas Gerais: Leandro L. Ticle, Fabricio L.S. Coutinho, Flávio
J. Reis, Gustavo O. Ribeiro, Júlio S. Vasconcelos, Paulo
R. Carvalho, Marcos L. P. Fereira.