Self-perceived weight status, dieting and unhealthy weight-control behaviors among Spanish male adolescents

Abstract

Introduction: Self-perceived weight status among adolescents has been associated with weight-control behaviors. However, this relationship varies across weight status.
Objectives: The aim of this study was to examine the effect of self-perceived weight status on dieting and unhealthy weight-control behaviors among Spanish male adolescents, across weight status. Method: Participants were 597 Spanish male adolescents (M = 13.94 years old, SD = 0.60). Body weight and height were measured in situ. Self-perceived weight status, dieting, and unhealthy weight-control behaviors
were evaluated. Results: The adolescents were inaccurate on estimating their weight status. Those who were overweight or obese, or who perceived themselves to be so, were more likely to report dieting and unhealthy weight-control behaviors. Discussion: There is a need to promote healthier eating behaviors among adolescents, and to take into account the fact that self-perceived weight status may hinder the adoption of such behaviors.

Full text

Nutr Hosp. 2014;30(2):301-305
ISSN 0212-1611 • CODEN NUHOEQ
S.V.R. 318
Original / Obesidad
Self-perceived weight status, dieting, and unhealthy weight-control
behaviors among Spanish male adolescents
Carlos A. Almenara1,2, Jordi Fauquet3,4, Gemma López-Guimerà2, Montserrat Pamias Massana5and
David Sánchez-Carracedo2
1Institute for Research on Children, Youth and Family. Department of Psychology. Faculty of Social Studies. Masaryk
University. Brno. Czech Republic. 2Unit for Research on Eating and Weight-related Behaviors. Dept. Clinical and Health
Psychology. Universitat Autònoma de Barcelona. Barcelona. Spain. 3Dept. Psychobiology and Methodology of Health
Sciences. Universitat Autònoma de Barcelona. Barcelona. Spain. 4Neuroimaging Research Group. IMIM (Hospital del Mar
Medical Research Institute). Barcelona Biomedical Research Park. Barcelona. Spain. 5Mental Health Unit of the Parc Taulí
Health Corporation (CSPT). Sabadell. Barcelona. Spain.
ESTATUS DE PESO PERCIBIDO, DIETA Y
CONDUCTAS NO SALUDABLES DE CONTROL
DEL PESO EN ADOLESCENTES VARONES
ESPAÑOLES
Resumen
Introducción: El estatus de peso percibido se ha aso-
ciado a conductas de control del peso en adolescentes.
Esta relación varía de acuerdo al estatus de peso corporal.
Objetivos: Explorar el efecto del estatus de peso perci-
bido sobre la práctica de dieta y conductas no saludables
de control del peso en adolescentes varones españoles,
considerando su estatus de peso.
Método: Participaron 597 adolescentes (M = 13,94
años, DS = 0,60). Se registró in situ la talla y peso corpo-
ral. Se evaluó el peso percibido, la práctica de dieta y con-
ductas no saludables de control del peso.
Resultados: Los adolescentes fueron inexactos al esti-
mar su estatus de peso. Aquellos con sobrepeso, obesidad
o los que se percibían como tales, fueron los que más
informaron hacer dieta y conductas no saludables de con-
trol del peso.
Discusión: Es necesario promover conductas alimenta-
rias saludables entre los adolescentes y considerar que el
estatus de peso percibido puede limitar la adopción de
estos comportamientos.
(Nutr Hosp. 2014;30:301-305)
DOI:10.3305/nh.2014.30.2.7596
Palabras clave: Imagen corporal. Peso corporal. Adoles-
cente. Factores de sexo. Pérdida de peso. Peso percibido.
Abstract
Introduction: Self-perceived weight status among
adolescents has been associated with weight-control
behaviors. However, this relationship varies across
weight status.
Objectives: The aim of this study was to examine the
effect of self-perceived weight status on dieting and
unhealthy weight-control behaviors among Spanish male
adolescents, across weight status.
Method: Participants were 597 Spanish male adoles-
cents (M = 13.94 years old, SD = 0.60). Body weight and
height were measured in situ. Self-perceived weight
status, dieting, and unhealthy weight-control behaviors
were evaluated.
Results: The adolescents were inaccurate on estimating
their weight status. Those who were overweight or obese,
or who perceived themselves to be so, were more likely to
report dieting and unhealthy weight-control behaviors.
Discussion: There is a need to promote healthier eating
behaviors among adolescents, and to take into account
the fact that self-perceived weight status may hinder the
adoption of such behaviors.
(Nutr Hosp. 2014;30:301-305)
DOI:10.3305/nh.2014.30.2.7596
Key words: Body image. Body weight. Adolescent. Sex fac-
tors. Weight loss. Self-perceived weight status.
301
Correspondence: Carlos A. Almenara.
Institute for Research on Children, Youth and Family.
Faculty of Social Studies. Masaryk University.
Joštova, 10.
602 00 Brno. Czech Republic.
E-mail: carlos.almenara@mail.muni.cz
Recibido: 15-V-2014.
Aceptado: 5-VI-2014.
11. SELF-PERCEIVED_01. Interacción 25/08/14 14:32 Página 301

Abbreviations
UWCB: Unhealthy weight-control behaviors.
SD: Standard deviation.
MABIC: Medios de comunicación, alimentación
alterada, burlas relacionadas con el peso e insatisfac-
ción corporal.
CSPT: Corporació Sanitària Parc Taulí.
BMI: Body Mass Index.
EAT: Eating Among Teens.
Introduction
Dieting and unhealthy weight-control behaviors
(UWCB), such as fasting, eating very little and skipping
meals are common behaviors among adolescents trying
to lose weight.1Unfortunately, these behaviors tend to
take place in a naturalistic way (ie without professional
advice), increasing the risk of unhealthy eating patterns
and weight gain over time.1 Several external factors may
contribute to promoting these UWCB among adoles-
cents. For instance, the multi-billion dollar weight-loss
industry, public health campaigns for tackling the so-
called “obesity epidemic” or pressure from peers and
parents may, directly or indirectly, encourage adoles-
cents to adopt UWCB so as to lose weight. Even so,
other, more individual factors can also facilitate the adop-
tion of UWCB.
A significant individual factor is self-perceived body
weight (ie how we perceive our own body weight).
However, few studies have taken into account that this
self-perception may vary by weight status, and may influ-
ence the adoption of eating and weight-related behaviors
in different ways. In particular, an inaccurate self-percep-
tion of body weight can promote the adoption of unhealthy
eating patterns and behaviors among the overweight and
obese,2and increase the risk of weight preoccupations and
weight control among normal-weight adolescents.3
In addition, recent studies have revealed secular trends
over time in relation to self-perceived body weight
among Spanish adolescents.4 Specifically, such research
found a pattern of change toward the underestimation of
overweight status, suggesting that the steady increase of
the overweight population may make weight mispercep-
tion more likely, especially among overweight men.
Thus, it is important in this context to examine the role of
self-perceived body weight in relation to the adoption of
dieting and UWCB.
Accordingly, the aim of the present study was to
examine the role of self-perceived weight status in
dieting and UWCB among Spanish male adolescents
of different weight status.
Method
Sample and procedure
The sample comprised 597 boys (13 to 16 years old;
M= 13.94, SD = 0.60), predominantly middle-class
(79.5%).6Self-reported origin was typically Spanish
(73.8%), followed by Latin-American (12.2%), mixed
parentage (5.4%), North African (3.2%), European
(2.5%), Sub-Saharan (1.2%), and other (1.7%). Partici-
pants were part of the MABIC project, a longitudinal
research project on the prevention of eating- and
weight-related problems among adolescents of both
sexes from Barcelona (Spain).5The study followed the
ethical guidelines of the Helsinki Declaration (as
revised in Edinburgh, 2000). The protocol was
approved by the Clinical Research Ethics Committee
of the “Parc Taulí” Health Corporation (CSPT). A
detailed description of the methodology has been
reported previously.5
Materials
Measured weight status. Height and weight were
measured in situ. Body mass index (BMI = kg/m2), was
calculated and used to obtain weight-status categories
(underweight, normal weight, overweight, obese),
using international cut-off points for age and sex.7,8
Self-perceived weight status. Participants were
asked “What do you think is your current weight
level?” Response options were: underweight, normal
weight, slightly overweight, very overweight.
Dieting. Based on Project EAT,9participants were
asked “How often have you gone on a diet during the
last year?” Next to the question the term diet was
defined as “changing the way you eat so you can lose
weight”. Response options were: “never”, “one to four
times”, “five to 10 times”, “more than 10 times”, and “I
am always dieting”. Following previously-reported
criteria,10 respondents who reported having dieted at
least once were classified as dieters.
Unhealthy weight-control behaviors (UWCB). Also
based on Project EAT, participants were asked “Have
you done any of the following things in order to lose
weight or keep from gaining weight in the past year?”
Response options were: “skipped meals”, “fasted”, “ate
very little food”, “smoked more cigarettes” “used a food
substitute”, “made myself vomit”, “took diet pills”, “used
laxatives”, and “used diuretics”. Response format was
dichotomous (‘yes’, one point; ‘no’, zero points). As in
previous studies,10 respondents reporting at least one
behavior were classified as engaging in UWCB.
Data Analyses
First, descriptive analyses were performed to
examine the sample in terms of weight status
(measured, self-perceived), and behaviors (dieting,
UWCB). Second, logistic regression analysis was used
to obtain the odds of dieting and then of UWCB. Each
logistic regression was controlled for age, ethnicity,
and socioeconomic status. Predictors were measured
weight status and self-perceived weight status.
302 Carlos A. Almenara et al.
Nutr Hosp. 2014;30(2):301-305
11. SELF-PERCEIVED_01. Interacción 25/08/14 14:32 Página 302

Results
Mean BMI was 20.94 (SD = 4.18); 44 boys were
obese (7.4%), 116 overweight (19.6%), 384 normal
weight (64.8%) and 49 underweight (8.3%).
Self-perceived weight status
Comparing measured weight status with self-
perceived weight status (table I), only 13.6% of obese
adolescents self-perceived as very overweight, 40.5%
of overweight adolescents self-perceived as normal
weight, and 42.9% of underweight adolescents self-
perceived as normal weight. These results indicate that
a substantial number of adolescents were inaccurate on
estimating their weight status.
Dieting and unhealthy weight-control behaviors
In descriptive terms, a total of 25.6% of adolescents
were classified as dieters (8.2% of underweight, 12.5% of
normal weight, 55.2% of overweight, and 77.3% of
obese). Regarding UWCB, 25% of adolescents reported
at least one UWCB (20.4% of underweight, 17.4% of
normal weight, 38.8% of overweight, and 56.8% of
obese). These results indicate that a high percentage of
overweight and obese adolescents reported being
engaged in dieting and UWCB. Notably, some already
underweight boys also reported dieting and UWCB.
Dieting and unhealthy weight-control behaviors
by measured weight status and by self-perceived
weight status
The underweight group (n = 49), was removed from
subsequent analyses because of the small number of
cases reporting dieting and UWCB in each category.
Next, and before carrying out the logistic regression
analyses, measured weight status and self-perceived
weight status were reduced to two categories each.
Thus, measured weight-status categories were reduced
to (1) normal weight and (2) overweight, including
obese; self-perceived weight-status categories were
reduced to (1) self-perceived normal weight and (2)
self-perceived slightly overweight or very overweight.
Table II shows the odds of dieting and UWCB from
the logistic regression analyses.
The odds of dieting and UWCB were statistically
significant on comparing those who were either over-
weight or obese (or self-perceived as such), with those
who were normal weight (or self-perceived as such).
These results indicate that, in general, either being or
self-perceiving as overweight or obese increases the
Adolescents’ self-perceived weight status 303Nutr Hosp. 2014;30(2):301-305
Table I
Self-perceived weight status by measured weight status*
Measured weight status
UW†NW‡OW§OB|Total
N 49 384 116 44
Self-perceived weight status
Underweight 55.1 9.9 0 0 10.9
Normal weight 42.9 85.1 40.5 9.1 66.9
Slightly overweight 0 5.0 58.6 77.3 20.6
Very overweight 2.0 0 0.9 13.6 1.5
Total 8.3 64.8 19.6 7.4 100
*Data is given as percentage. Total n values may differ because of incidental missingness.
†UW = underweight.
‡NW = normal weight.
§OW = overweight.
|OB = obese.
Table II
Odds Ratio (OR) indicating the effect of weight status
on dieting and unhealthy weight-control behaviors
(UWCB)*
Variables OR Wald 95% CI
Dieting
MWS†10.74 108.95 6.88-16.77
SPWS‡11.15 103.61 7.01-17.73
MWS × SPWS§12.71 105.55 7.83-20.65
UWCB
MWS 3.47 34.38 2.29-5.27
SPWS 2.74 21.19 1.78-4.22
MWS × SPWS 2.79 20.31 1.79-4.37
*Analyses were adjusted by ethnicity, age, and socioeconomic status.
Weight status categories (measured, self-perceived) were: normal weight
and overweight including obese. Reference group was normal weight. Re-
sults in bold were significant (p < 0 .001).
†MWS = measured weight status.
‡SPWS = self-perceived weight status.
§MWS × SPWS = interaction between these two variables.
11. SELF-PERCEIVED_01. Interacción 25/08/14 14:32 Página 303

risk of dieting and UWCB. It is noteworthy that the risk
of dieting was slightly higher among those who self-
perceived as overweight or obese. In contrast, the risk
of UWCB was slightly higher among those who were
actually overweight or obese.
Discussion
The aim of the present study was to examine the
effect of self-perceived weight status on dieting and
UWCB among Spanish male adolescents of different
weight status.
We found that overweight and obese adolescents
tended to underestimate their weight status, whereas
underweight adolescents tended to overestimate it. This
finding has been reported previously, 3and merits
further attention. For example, weight-related norms
(eg what is perceived as a normal body weight in a
given context) may influence how adolescents perceive
and estimate their body size.11 These social norms are
commonly linked to an ideal of beauty or attractiveness
in a given context. 12 In Western countries such as
Spain, boys may be aware of a male beauty/attractive-
ness ideal (eg a lean and muscular body), and may
perceive sociocultural pressure (eg messages from
peers and the media) to attain this ideal.13 Thus, over-
weight and obese adolescents might underestimate
their weight because of the double burden of sociocul-
tural pressure and the stigma of obesity.14 This could
have a strong influence on how they perceive and esti-
mate their body size,15 to the extent that they may reject
referring to themselves as overweight or obese. Alter-
natively, it may be that these overweight and obese
adolescents perceive their weight as “normal” given the
steady increase in the proportion of overweight and
obese adolescents in Spain.4However, these ideas
remain speculative, and further research is recom-
mended. Furthermore, given the frequency of weight
underestimation among overweight and obese adoles-
cents, future studies should use caution on considering
obesity prevalence based on self-reported data. In addi-
tion, the finding whereby underweight boys overesti-
mate their weight could be explained by their having
perceived their body size as closer to the ideal, so that
they estimate their weight as “normal”. Notably, few
studies have examined weight overestimation among
underweight boys.3Most probably, boys in this group
have a body image disturbance, an eating disorder, or a
higher risk of developing an eating disorder.3Neverthe-
less, this cannot be supported by our findings. There-
fore, future studies evaluating body image attitudes and
behaviors among underweight boys who overestimate
their weight are recommended. Finally, professionals
in the public health field must bear in mind that weight
misperceptions among adolescents, either underesti-
mation or overestimation, can interfere with the imple-
mentation of strategies for promoting healthy eating-
and weight-related behaviors.2
As regards the prevalence of dieting and UWCB by
weight status, the highest prevalence was found among
obese adolescents. However, it should be noted that
some already underweight boys also reported these
behaviors. This finding is consistent with those of
previous studies,1,10,16 and highlights once more the
importance of examining eating- and weight-related
behaviors separately by weight status, as well as the
need to further evaluate the risk of disordered eating
among those in the extreme categories.
We also examined the effect of measured weight
status and self-perceived weight status on the risk of
dieting and UWCB. Our results suggest that either
being or perceiving oneself as overweight or obese
substantially increases the risk of dieting and UWCB,
compared to being or self-perceiving normal weight.
Notably, the risk of dieting was slightly higher if boys
self-perceived as overweight or obese. This finding is
consistent with the previous literature, including a
large cross-national study.16 However, it is also note-
worthy that the risk of UWCB in our sample was
slightly higher if boys were actually overweight or
obese. Thus, our results may again suggest that other
factors, such as weight-related norms,11 may influence
the risk of dieting and UWCB. For instance, it may be
commonly accepted among these boys to engage in
dieting if they are or self-perceive as overweight or
obese. However, this idea remains speculative, and
future studies should assess the role of social norms in
relation to dieting and UWCB on comparing measured
and self-perceived weight-status categories. In any
case, these adolescents may be engaging in dieting
behaviors without professional advice, and this can
increase their risk of unhealthy eating patterns.1Conse-
quently, health professionals should be aware of these
behaviors and how self-perceived weight might influ-
ence eating patterns and behaviors of adolescents.
Finally, and with a view to avoiding unintended poten-
tially harmful effects such as promoting weight stigma-
tization and weight concerns, health professionals
should help adolescents to adopt healthy eating- and
weight-related behaviors focusing more on their
overall wellness than exclusively on weight loss.17
This study has some limitations, and its results
should be interpreted with caution. First, this is a cross-
sectional study, so that the inferences that can be made
are limited; more longitudinal studies are necessary.
Second, our sample is not representative of the entire
population of Spanish male adolescents, and few
participants were in the extreme weight-status cate-
gories (underweight, obese). For these reasons, any
generalizations should be made with care. Finally, we
used some self-report measures that could bias the
results due to under-reporting or over-reporting of
behaviors. However, our study has some important
strengths and implications. Few studies have examined
the effect of self-perceived weight status on dieting and
UWCB by including an objective measure of body
weight and height, and by controlling for recognized
304 Carlos A. Almenara et al.
Nutr Hosp. 2014;30(2):301-305
11. SELF-PERCEIVED_01. Interacción 25/08/14 14:32 Página 304

confounding variables. Objective measures of weight
and height generate more accurate data than self-
reported measures. Additionally, we used international
cut-off points to establish weight status, and these are
recommended so as to allow comparability among
surveys.18 Furthermore, logistic regression analyses
were done by controlling for ethnicity and socioeco-
nomic status, variables widely acknowledged to influ-
ence self-perceived weight.11 Finally, our results on
weight misperception are of great importance for
future research. Weight misperception may be associ-
ated with weight-related norms referring to a norma-
tive perceptual threshold for overweight in specific
populations,11 or to the trends in body weight misper-
ception observed over the last decades,4 and this is a
clear hint for professionals in the obesity field to give
greater attention to self-perceived weight status.
Acknowledgments
This article was supported by research grants from
the Spanish Ministry of Science and Innovation
[PSI2009-08956] and Ministry of Economy and
Competitiveness [PSI2012-31077].
References
1. Field AE, Austin SB, Taylor CB, Malspeis S, Rosner B,
Rockett HR, Gillman MW, Colditz GA. Relation between
dieting and weight change among preadolescents and adoles-
cents. Pediatrics 2003; 112 (4): 900-6. PubMed PMID:
14523184.
2. Duncan DT, Wolin KY, Scharoun-Lee M, Ding EL, Warner
ET, Bennett GG. Does perception equal reality? Weight
misperception in relation to weight-related attitudes and behav-
iors among overweight and obese US adults. Int J Behav Nutr
Phys Act 2011; 8: 20. PubMed PMID: 21426567.
3. Deschamps V, Salanave B, Chan-Chee C, Vernay M,
Castetbon K. Body-weight perception and related preoccupa-
tions in a large national sample of adolescents. Pediatr Obes
Epub 2014 Jan 23; PubMed PMID: 24453118.
4. Salcedo V, Gutiérrez-Fisac JL, Guallar-Castillón P, Rodríguez-
Artalejo F. Trends in overweight and misperceived overweight
in Spain from 1987 to 2007. Int J Obes 2010; 34 (12): 1759-65.
PubMed PMID: 20498661.
5. Sánchez-Carracedo D, López-Guimerà G, Fauquet J, Barrada
JR, Pàmias M, Puntí J, Querol M, Trepat E. A school-based
program implemented by community providers previously
trained for the prevention of eating and weight-related prob-
lems in secondary-school adolescents: the MABIC study
protocol. BMC Public Health 2013; 13 (1): 955. PubMed
PMID: 24118981.
6. Hollingshead A de B. Two factor index of social position. New
Haven, CT: Yale Station; 1957.
7. Cole TJ, Bellizzi MC, Flegal KM, Dietz WH. Establishing a
standard definition for child overweight and obesity world-
wide: International survey. BMJ 2000; 320 (7244): 1240-1240.
PubMed PMID: 10797032.
8. Cole TJ, Flegal KM, Nicholls D, Jackson AA. Body mass index
cut offs to define thinness in children and adolescents: Interna-
tional survey. BMJ 2007; 335 (7612):194. PubMed PMID:
17591624.
9. Neumark-Sztainer DR, Story M, Hannan PJ, Perry CL, Irving
LM. Weight-related concerns and behaviors among overweight
and nonoverweight adolescents: Implications for preventing
weight-related disorders. Arch Pediatr Adolesc Med 2002; 156
(2): 171-8. PubMed PMID: 11814380.
10. López-Guimerà G, Neumark-Sztainer DR, Hannan PJ, Fauquet
J, Loth K, Sánchez-Carracedo D. Unhealthy weight-control
behaviours, dieting and weight status: A cross-cultural compar-
ison between North American and Spanish adolescents. Eur
Eat Disord Rev 2013; 21 (4): 276-83. PubMed PMID:
23055262.
11. Johnson WG, Stewart R, Pusser AT. The perceptual threshold
for overweight. Eat Behav 2012; 13 (3): 188-93. PubMed
PMID: 22664395.
12. Mills JS, Jadd R, Key BL. Wanting a body that’s better than
average: The effect of manipulated body norms on ideal body
size perception. Body Image 2012; 9 (3): 365-72. PubMed
PMID: 22494959.
13. McCabe MP, Ricciardelli LA, Sitaram G, Mikhail K. Accuracy
of body size estimation: Role of biopsychosocial variables.
Body Image 2006; 3 (2): 163-71. PubMed PMID: 18089219.
14. Puhl RM, Latner JD. Stigma, obesity, and the health of the
nation’s children. Psychol Bull 2007; 133 (4): 557-80. PubMed
PMID: 17592956.
15. Sand L, Lask B, Høie K, Stormark KM. Body size estimation in
early adolescence: Factors associated with perceptual accuracy
in a nonclinical sample. Body Image 2011; 8 (3): 275-81.
PubMed PMID: 21570368.
16. Ojala K, Vereecken CA, Välimaa R, Currie C, Villberg J,
Tynjälä J, Kannas L. Attempts to lose weight among over-
weight and non-overweight adolescents: A cross-national
survey. Int J Behav Nutr Phys Act 2007; 4 (50). PubMed PMID:
17935629.
17. Pinhas L, McVey GL, Walker KS, Norris M, Katzman D,
Collier S. Trading health for a healthy weight: The uncharted
side of healthy weights initiatives. Eat Disord 2013; 21 (2):
109-16. PubMed PMID: 23421694.
18. De Onis M, Lobstein T. Defining obesity risk status in the
general childhood population: Which cut-offs should we use?
Int J Pediatr Obes 2010; 5 (6): 458-60. PubMed PMID:
20233144.
Adolescents’ self-perceived weight status 305Nutr Hosp. 2014;30(2):301-305
11. SELF-PERCEIVED_01. Interacción 25/08/14 14:32 Página 305