Association between dental caries and obesity among Libyan schoolchildren during the armed conflict in Benghazi

Abstract

Background
Dental caries and Obesity in children are issues of public health concern. Even though researching the relationship between these two noncommunicable diseases has been conducted for many years, the results remain equivocal. This paper aimed to examine the association between dental caries and obesity among 12-year-old schoolchildren living in war-affected environment in Benghazi.

Methods
A secondary analysis of a cross-sectional study was conducted to determine the prevalence of caries among 12-year-old school children in Benghazi in 2017 during the armed conflict that affected the city. The data extracted for the analysis included sociodemographic of the participants (gender, maternal education and school type), caries experience (DMFT index), and anthropometric measures (height in cm, weight in kg, BMI and Z score for BMI). Comparisons of anthropometric measures were conducted according to caries experience. Linear regression models were developed to determine the association between Body Mass Index and Z score as outcome variables, caries as an explanatory variable, and covariates (gender, maternal education and school type). Beta coefficient (β) and 95% confidence intervals were calculated. All statistical tests were conducted at p ≤ 0.05.

Results
There were 782 children with a mean (SD) BMI of 20.7 SD5.09 and an average z (SD) score of 0.56 SD1.51. Also, 159 (20%) children had obesity. No significant association was observed between caries and anthropometric measures. However, higher BMI was observed in children from a private school ( p ≤ 0.001***), females ( p ≤ 0.001***) and self-reported regular sugary drinks consumers ( p ≤ 0.001***).

Conclusion
The present study shows no significant association between dental caries and anthropometric measures. However, the study findings support the notion of tackling sugar intake as a common risk factor for caries and obesity, which should be encouraged in the Libyan culture.

Full text

Aounetal. BMC Oral Health (2023) 23:44
https://doi.org/10.1186/s12903-023-02728-2
RESEARCH
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Open Access
BMC Oral Health
Association betweendental caries
andobesity amongLibyan schoolchildren
duringthearmed conict inBenghazi
Entesar Aoun, Lamis Ballo, Sara Elhabony* and Arheiam Arheiam
Abstract
Background Dental caries and Obesity in children are issues of public health concern. Even though researching the
relationship between these two noncommunicable diseases has been conducted for many years, the results remain
equivocal. This paper aimed to examine the association between dental caries and obesity among 12-year-old school-
children living in war-affected environment in Benghazi.
Methods A secondary analysis of a cross-sectional study was conducted to determine the prevalence of caries
among 12-year-old school children in Benghazi in 2017 during the armed conflict that affected the city. The data
extracted for the analysis included sociodemographic of the participants (gender, maternal education and school
type), caries experience (DMFT index), and anthropometric measures (height in cm, weight in kg, BMI and Z score for
BMI). Comparisons of anthropometric measures were conducted according to caries experience. Linear regression
models were developed to determine the association between Body Mass Index and Z score as outcome variables,
caries as an explanatory variable, and covariates (gender, maternal education and school type). Beta coefficient (β)
and 95% confidence intervals were calculated. All statistical tests were conducted at p ≤ 0.05.
Results There were 782 children with a mean (SD) BMI of 20.7 SD5.09 and an average z (SD) score of 0.56 SD1.51.
Also, 159 (20%) children had obesity. No significant association was observed between caries and anthropometric
measures. However, higher BMI was observed in children from a private school (p ≤ 0.001***), females (p ≤ 0.001***)
and self-reported regular sugary drinks consumers (p ≤ 0.001***).
Conclusion The present study shows no significant association between dental caries and anthropometric measures.
However, the study findings support the notion of tackling sugar intake as a common risk factor for caries and obesity,
which should be encouraged in the Libyan culture.
Keywords Dental caries, Obesity, Children, Libya, Observational study
Introduction
Libya, a war-torn North African country, that since the
year 2011 endured several military conflicts and a finan-
cial crisis. Benghazi, the second largest city and the capi-
tal of Libyan east province, was locked in armed conflict
that lasted three years since May 2014 and has resulted in
life hardships affecting social and behavioural aspects of
life [1]. One of the health-related consequences of con-
flict was the drop in sugar consumption among Libyan
*Correspondence:
Sara Elhabony
Sarahabony@gmail.com
Department of Dental Public Health and Preventive Dentistry, Faculty
of Dentistry, University of Benghazi, Benghazi, Libya
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children, an undebated common risk factor for many
health conditions [2]. Obesity and caries are global public
health problems that have significant burdens, negatively
impact the quality of life and share sugar consumption
as a common risk factor [3]. e available data suggests
that 16.9% of children aged five or younger and 6.1% of
children aged between 10 and 18 were obese. Obesity
among Libyan children and adolescents is increasing due
to adopting a western diet rich in fat and sugars [4]. Fur-
thermore, the impact of decreased sugar intake during
the Libyan conflict has been demonstrated in a relatively
recent study showing a concurrent decrease in caries and
sugar intake compared to pre-conflict higher prevalence
of dental caries [1]. However, searching literature indi-
cated that no recent studies had been conducted to assess
obesity and its risk factors among Libyan children dur-
ing the Libyan conflict. Lacking pre-conflict obesity data
makes it impossible to assess whether the prevalence of
obesity is affected by decreased sugar intake during the
conflict, in spite of the facts that sugar intake is a com-
mon risk factor for caries and obesity [5]. Moreover, both
conditions are multifactorial, with an interplay between
biological, genetic, socioeconomic, cultural, dietary, envi-
ronmental, and lifestyle risk factors [6]. erefore, it is
unclear to what extent the reduced sugar intake during
the conflict has affected the distribution of obesity.
e relationship between caries and obesity has
received much attention in recent years. However, the
evidence from several systematic is equivocal [7–13],
which is partly attributed to inconsistencies in assess-
ment and measurements of both conditions [10, 14].
More importantly, the previous reviews highlighted the
need to adjust the caries-obesity relationship for the
social environment and sugar intake, which are well-
known common risk factors for both caries and obesity
[15, 16]. e theoretical model of social determinants
of health have suggested that health outcomes are influ-
enced by behavioural determinants, which in turn are
influenced by wider social determinants [5]. is theo-
retical explanation allows for policy development and
planning of public health interventions which should be
tailored to the social environment and behaviours. For
example, there is evidence that associations between den-
tal caries and obesity in children vary by country-level
income [13]. In addition, several studies conducted in
low-Middle income countries reported conflicting find-
ings regarding the association between caries and obesity
[17–22]. For example, recent studies conducted in India
[23] and Egypt [24] demonstrated variations in caries-
obesity relationship and sugar consumption. It is, there-
fore, helpful to assess the association between caries and
obesity in different environmental and social contexts
where there are variations in obesogenic behaviours,
dietary habits, and cultural habits. Given this, the pre-
sent study aimed to investigate the association between
caries and obesity among schoolchildren living in a war-
affected environment in Benghazi and to evaluate the
role of family socioeconomic status and sugar consump-
tion in explaining this association.
Methods
Permission to use the primary data was obtained from
the Department of Dental Public Health at the University
of Benghazi. Research Ethics Committee approved the
study at the Faculty of Dentistry, University of Benghazi
(Ref No: UOB-053). e reporting of the study followed
the statement outlined in strengthening the reporting of
observational studies in Epidemiology (STROBE).
Study design andsetting
A secondary analysis was conducted on primary data
collected in 2017, during wartime in Benghazi, as part
of a cross-sectional survey of 12-year-old school chil-
dren. Benghazi is the second largest city in the country,
with nearly a million inhabitants from different families
and tribes. Hence, this population is deemed representa-
tive of all Libyans. e education system is comprised of
the public and private sectors. e ministry of education
divided the city of Benghazi into eight administrative dis-
tricts based on the geographic distribution of the popula-
tion and representing urban and suburban populations.
Study population
e participants were recruited from public and pri-
vate schools in Benghazi. It was estimated that 13,000
12-year-old schoolchildren were registered in 2016/2017.
e students were distributed over 267 schools, and
around 75% were enrolled in public schools. A study
sample of 1200 pupils was selected using a two-stage
random sampling strategy. In the first stage, a random
sample of 40 public and private schools were selected
proportionally from 8 administrative districts in Beng-
hazi. e average number of students in each classroom
was 30. erefore, one classroom was selected randomly
from each school. Informed consent was first sought
from the parents and sent to them through the school
administrator’s office. A detailed description of the origi-
nal sample calculations has been provided elsewhere [1].
e aim of the study was explained to the children, and
verbal assent was implied by accepting to attend the den-
tal examination. A total of 1134 parents returned signed
consent forms and completed questionnaires usable for
data analysis. Only Libyan children who had lived in
the city of Benghazi since their birth were recruited for
the study. Children diagnosed with a mental or physical
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disability, undergoing orthodontic treatment, with hypo-
plastic teeth or moderate to severe dental fluorosis were
excluded.
For the current study, incomplete data in which the
date of birth, height, or weight was missing was removed.
As a result, 782 participants were included in the analy-
sis. Post-hoc power analysis demonstrated that this sam-
ple size is sufficient to assess the association between
obesity and caries at 99% power at statistical significance
of 0.05, and 95% confidence intervals.
Measurements
Dental caries measurements
Dental caries lesions were assessed according to World
Health Organization (WHO) diagnostic criteria (at the
dentine level) by using the DMFT index [1]. e den-
tal examination was conducted for all participants in
a separate classroom under natural daylight while the
participant was seated on an ordinary chair using dis-
posable diagnostic kits. ree dentists were trained and
calibrated to carry out the clinical dental examinations.
Kappa coefficients were 0.88–0.96 for inter-examiner and
intra-examiner reliability. e training sessions were pro-
vided at the Department of Pediatric Dentistry, Univer-
sity of Benghazi, before commencing the data collection.
Anthropometric measurements
e investigators conducted the anthropometric meas-
urements. Height was measured in cm, with the child
standing without shoes using a portable stadiometer.
Weight in kg was measured using a pre-calibrated digi-
tal Seca scale, with children wearing light clothes and
no shoes. e measurements for height and weight were
taken to the nearest 0.1cm and 0.1kg, respectively. BMI
and BMI-adjusted z-scores for Age and gender (BAZ)
were computed based on WHO growth references data
for children aged 5–19 years using the WHO Anthro-
plus software program.[2, 25].
Questionnaire
e questionnaire was developed from previous stud-
ies and guided by the study’s research questions [1].
Before data collection, the questionnaire was tested for
clarity and readability among a group of dental patients
and schoolchildren. e questionnaire collected soci-
odemographic data (children’s date of birth, gender
and parental educational level). In addition, the ques-
tionnaire included items related to oral health-related
behaviours (for example: whether they brushed their
teeth regularly) and dietary habits such as timing and
frequency of sugar intake (never, sometimes, once per
day, twice or more per day). e questionnaire was
paper based and handed out by a trained assistant to
the children to complete with the assistance of their
parents.
Data management andanalysis
e data extracted for the present study were how
frequently sugary drinks and foods are consumed,
which was then dichotomized as infrequent (never
and sometimes), and frequent (once per day, twice or
more per day), caries as present (DMFT ≥ 1) or absent
(DMFT = 0), maternal education (less than university
vs. university or higher), and school type (public vs.
private) [26]. e third model of WHO Anthro-Plus
was used to compute BMI and BAZ from the original
data. e participants were grouped into four catego-
ries: low weight, average weight, overweight, and obese,
following the cut-off points of < − 2 SD, ≥ − 2 SD— + 1
SD, > + 1 SD— + 2 SD, and > + 2SD z-scores, respec-
tively [27]. e data was then uploaded to SPSS 25 soft-
ware for analysis. Descriptive statistics were conducted
to summarise the sample profile, regular dietary habits,
height, weight, BMI and Z-scores. Bivariate compari-
son using the independent sample t-test was used to
compare anthropometric measures (height and weight),
BMI and BAZ according to children’s school type, caries
experience, maternal education and sugar intake. Mul-
tilevel multiple linear regression analysis was used to
assess the association between BMI and BAZ (depend-
ent variable) and fixed effect factors including level 1
(child) factors: caries experience, gender, maternal edu-
cation, sugar intake and level 2 (school) factors: public
versus private). e analysis was built on the common
risk approach for tackling non-communicable diseases.
Obesity and caries share common risk factor such as
sugar intake and social position in the community [5,
6]. erefore, association was examined between caries
(as predictor) and obesity (as an outcome) and social
characteristics as well as sugar intake were included
as confounders. An unconditional model (without
fixed effect variables) was first created as baseline.
is was followed by three conditional models includ-
ing child, school and combined child-school factors
as fixed effects. Improvement in model fit due to the
added fixed effect variables was assessed using model
deviance (− 2LL) and covariance parameter estimates.
Adjusted regression coefficients (B) and their respec-
tive 95% confidence intervals (CI) were estimated and
reported. A two-way ANOVA was conducted to exam-
ine the effect of school type and sugar consumption on
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BAZ and caries experience (DMFT). All statistical tests
were conducted with a p value set at ˂0.05.
Results
Data from 782 children aged 12years were included in
the analysis. Most of them were from public schools
(591, 75.6%). More than half of the participants were
males (422, 54%), and more than half did not have caries
(437,55.9%). Slightly less than half of the mothers (329,
47.7%) did not attain a university education (Table 1).
Average weight was observed in the majority of the par-
ticipants (456, 58%), whereas obese children represented
(159, 20%) of the participants and a small proportion (43,
6%) were underweight.
Table1 shows summary statistics on anthropometric
measures and comparisons according to the participants’
gender, maternal education, caries, school type and con-
sumption of sugary drinks. e average BMI was 20.7
(SD = 5.09), and the average z-score was 0.56 (SD = 1.51).
Comparisons of anthropometric measures demonstrated
a statistically significant difference in BMI and weight
when compared by sugar intake frequency, school type
and gender. Regular consumers of sugary drinks had
higher average body weight (p ≤ 0.001) and BMI (p ≤ 0.00
compared to irregular consumers. Children who studied
in private schools have higher body weight (p ≤ 0.001)
and BMI (p ≤ 0.001) than those in public schools. Females
had higher height (p ≤ 0.001), body weight (p ≤ 0.001)
and BMI (p ≤ 0.001) than males.
Table 1 Comparisons of height, weight, BMI and Z-scores by caries experience, sugar consumption, school type and maternal
education (N = 782)
Independent sample t test was used to compare height, weight, BMI and Z-score across study subgroups. Height in cm, weight in kg
*≤ 0.05, **≤ 0.01, ***≤ 0.001, SD standard deviation
Variables Overall
N (%) Height
Mean (SD) Weight
Mean (SD) BMI
Mean (SD) Z score
Mean
(SD)
146.1
(9.59) 44.4
(12.93) 20.7 (5.09) 0.56 (1.51)
Sugary drinks
Regular 325 (41.6) 145.77
(9.49) 46.41
(13.60) 21.26
(5.37) 0.502 (1.5)
Irregular 457 (58.4) 146.37
(9.66) 42.27
(11.81) 20.08
(4.69) 0.508 (1.5)
p value 0.023* ≤ 0.001*** ≤ 0.001*** ≤ 0.001***
Caries
Present 345 (44.1) 145.26
(9.98) 43.01
(11.21) 20.42
(4.71) 0.49 (1.48)
No caries 437 (55.9) 146.79
(9.23) 45.44
(14.05) 20.90
(5.36) 0.52 (1.52)
p value ≤ 0.001*** ≤ 0.001*** 0.001** 0.479
School type
Private 191 (24.4) 145.9
(8.78) 45.97
(14.70) 21.36
(5.28) 0.62 (1.48)
Public 591 (75.6) 146.3
(10.4) 43.05
(11.03) 20.11
(4.85) 0.40 (1.52)
p value 0.116 ≤ 0.001*** ≤ 0.001*** ≤ 0.001***
Gender
Male 422 (54) 144.83
(9.84) 42.27
(11.8) 20.08
(4.69) 0.51 (1.51)
Female 360 (46) 147.32
(9.21) 46.41
(13.6) 21.26
(5.37) 0.50 (1.50)
p value ≤ 0.001*** ≤ 0.001*** ≤ 0.001*** 0.873
Maternal education
Less than University 329 (47.7) 146.23 (9.98) 44.40 (13.17) 20.66 (5.19) 0.48 (1.58)
University or higher 453 (52.3) 146.00 (9.56) 44.81 (13.26) 20.92 (5.25) 0.59 (1.42)
p value 0.446 0.280 0.090 0.014*
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Results of multilevel linear regression analyses
(Table2) revealed non statistically significant and weak
associations between DMFT and BAZ when adjusted
for child level factors [B = 0.02, 95% CI (− 0.04, 0.10);
p(0.56)] and both child level and school level factors
[B = 0.03, 95% CI (− 0.05, 0.10); p(0.47)]. No statisti-
cally significant association was reported between BAZ
and child or school level factors.
Table3 shows the results of multilevel linear regression
analysis for BMI as dependent variable. No statistically
significant association was reported between DMFT and
BMI, when adjusted for child level factors [B = − 0.08,
95% CI (− 0.32, 0.16); p(0.58)] and both child level and
school level factors [B = − 0.06, 95% CI (− 0.30, 0.18);
p(0.62)]. Significant associations between BMI and social
and behavioural factors were reported in separate models
Table 2 Association between BAZ and caries experience (DMFT) controlling for confounders using multilevel multiple linear
regression analysis
Conditional 1: including child level factors: DMFT and confounders (gender, maternal education and consumption of sugary drinks)
Conditional 2: including only school level factors (public vs. private, as confounder)
Conditional 3: including both child and school level factors
Unconditional Conditional 1
(with xed eect factors)
B (95% CI); [p value]
Conditional 2(with xed
eect factors) B (95% CI);
[p value]
Conditional 3(with
xed eect factors) B
(95% CI); [p value]
Child factors
DMFT – 0.02 (− 0.04, 0.10); [0.56] – 0.03 (− 0.05, 0.10); [0.47]
Gender:
Male versus Female – 0.06 (− 0.16, 0.28); [0.61] – 0.04 (− 0.19, 0.23); [0.74]
Maternal education
Less than University VS Univrsity – 0.08 (− 0.03, 0.43); [0.47] – 0.04 (− 0.20, 0.27); [0.75]
Sugary drinks
Infrequent versus frequent – 0.20 (− 0.14, 0.31); [0.08] – 0.20 (− 0.04, 0.34); [0.09]
School factors
School type
Public versus private – – 0.21 (− 0.03, 0.47); [0.08] 0.26 (− 0.01, 0.53); [0.06]
− 2LL 2865.6 2521.7 2862.5 2518.1
Covariance parameter: estimate (SE) 2.29 (0.12) 2.27 (0.12) 2.29 (0.12) 2.26 (0.12)
Table 3 Association between BMI and caries experience (DMFT) controlling for confounders using multilevel multiple linear
regression analysis
*p ≤ 0.05, **p ≤ 0.01
Conditional 1: including child level factors: DMFT and confounders (gender, maternal education and consumption of sugary drinks)
Conditional 2: including only school level factors (public vs. private, as confounder)
Conditional 3: including both child and school level factors
Unconditional Conditional 1
(with xed eect factors)
B (95% CI); [p value]
Conditional 2
(with xed eect factors)
B (95% CI); [p value]
Conditional 3
(with xed eect factors)
B (95% CI); [p value]
Child factors
DMFT – − 0.08(− 0.32, 0.17); [0.53] – − 0.06 (− 0.30, 0.18); [0.62]
Gender:
Male versus female – 0.89 (0.13, 1.67); [0.02*] – 1.01 (0.25, 1.77); [0.01**]
Maternal education
Less than University VS University – 0.06 (− 0.70, 0.83); [0.87] – − 0.18 (− 0.96, 0.50); [0.64]
Sugary drinks
Infrequent versus frequent – 0.83 (0.05, 1.61); [0.04*] – 0.80 (0.03, 1.58); [0.04*]
School factors
School type
Public versus private – – 1.24 (0.43,2.05); [0.003**] 1.43 (0.52, 2.33); [0.002**]
− 2LL 4731.6 4197.5 4722.6 4187.9
Covariance parameter: estimate (SE) 24.85 (1.25) 25.67 (1.38) 24.56 (1.24) 25.32 (1.36)
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for child level factors and school level factors. Higher
BMI was reported among frequent consumers of sug-
ary drinks [B = 0.83, 95% CI (0.05, 1.61); p(0.04)] females
[B = 0.89, 95% CI (0.13, 1.67); p(0.02)], and private
schools [B = 1.24, 95% CI (0.43, 2.05); p(0.003)]. e asso-
ciation remained statistically significant even after com-
bining child level and school level factors in one model.
Higher BMI was associated with frequent consumption
of sugary drinks [B = 0.80, 95% CI (0.03, 1.58); p(0.04)]
females [B = 1.01, 95% CI (0.25, 1.77); p(0.01)], and pri-
vate schools [B = 1.43, 95% CI (0.52, 2.33); p(0.002)].
Table4 shows the results of two-way ANOVA. ere
was a statistically significant interaction between the
effects of school type and sugar intake on Z score
(p = 0.001) and caries experience (p = 0.001). Children
from private schools who are frequent consumers of
sugars had the highest average Z-score (0.76, SD = 1.47).
On the other hand, public school children and infre-
quent consumers of sugars had the least Z-score (0.33,
SD = 1.52). On the contrary, public schools have higher
DMFT regardless of sugar consumption, though the low-
est score was among infrequent sugar consumers in pri-
vate schools (0.63, SD = 1.15).
Discussion
e present study sought to investigate the association
between caries and obesity among schoolchildren dur-
ing wartime and to evaluate the role of family socioeco-
nomic status and sugar consumption, as common risk
factors, in explaining this association. e data analysis
indicates that caries and obesity were negatively associ-
ated. However, after controlling for common risk factors,
this association became non-statistically significant when
obesity was measured using BMI and changed in direc-
tion when BAZ was used as an obesity measure. Similar
findings have been reported in a recent US study which
concluded that the caries-obesity relationship is influ-
enced by how they are measured and attenuated by com-
mon risk factors [14]. In addition, a negative association
between dental caries and BAZ has been observed in
studies conducted in Bangladesh [28] and Saudi Arabia
[29]. Taken together, these observations, while explain-
ing the inconclusive and conflicting findings reported in
several reviews regarding the association between obe-
sity and caries, it highlights the need to standardize the
measurement of caries and obesity in future studies.
e present study’s findings support the role of com-
mon behavioural and social risk factors in influencing the
association between caries and obesity. Although eco-
logical data of Libyan school children living in the war
environment linked reduced sugar intake to lower caries
levels [1], high sugar intake is a well-documented cause
of caries and obesity. erefore, the positive association
between sugar intake and obesity, observed in the pre-
sent study, is a reflection of individual intake and should
be by no means confused with per capita consumption of
sugars during wartime. Evaluating the impact of reduced
per-capita sugar intake during the conflict on obesity was
not possible in our study due to a lack of comparable pre-
conflict data on obesity among Libyan school children.
However, a high sugar intake can indicate unhealthy
behaviours such as increased consumption of fast foods,
which are energy-dense and ultra-processed [30] and
often combined with adopting a more sedentary lifestyle
[31]. ese behaviours are well-recognized as crucial
drivers of increased obesity. However, further research
is needed to understand the dietary habits of the Libyan
culture and its association with obesity to uncover dif-
ferent pathways that might be at play for obesity among
Libyan schoolchildren.
In the present study, higher BMI and BAZ were
observed in children studying in private schools
compared to their peers from public schools. is
observation supports a moderating role of the social
environment in the association between obesity and
caries [32]. On the other hand, children from pri-
vate schools had higher BAZ and lower DMFT score
than those from public schools, and these scores vary
according to the reported sugar consumption. One pos-
sible explanation for social variations in obesity and
dental caries might be the differences in dietary hab-
its, self-hygiene and lifestyle across the socioeconomic
spectrum and living environments [33]. Put simply,
it could be the case that children from higher income
families (indicated by private schools) are capable of
maintaining oral hygiene and has better access to den-
tal care, while also having more access to energy-dense
fast foods and video games that promote a sedentary
lifestyle. So, their social position increases their risk of
obesity and decreases their risk of caries, unlike their
peers from low-income families. However, this assump-
tion needs further investigation in future research
Table 4 Two-way ANOVA analysis of the effect of school type
and sugar intake on obesity and caries
**p ≤ 0.01
SCHOOL Sugary drinks BAZ DMFT
Mean SD Mean SD
Private Infrequent 0.42 1.46 0.63 1.15
Frequent 0.76 1.47 0.91 1.31
Public Infrequent 0.33 1.52 0.98 1.56
Frequent 0.45 1.52 1.00 1.54
p value for school-sugar interaction 0.001** 0.001**
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Page 7 of 8
Aounetal. BMC Oral Health (2023) 23:44
using a more controlled study design. Nevertheless, the
current study supports the notion that obesity and car-
ies risk are not directly related; instead, common risk
factors drive the development of both conditions. Fur-
thermore, these factors are influenced by wider social
determinants [14, 34].
To the authors’ best knowledge, the present study was
the first to assess the relationships between dental caries
and anthropometric measures among Libyan adolescents.
Our study provides baseline epidemiological data for both
investigating trends of obesity and its association with
dental caries in the future. e current study showed that
a fifth of the study participants were classified as obese,
which is way higher than what was previously estimated
among Libyan children [4]. is finding, while confirming
the projected increase in obesity in Libya due to adopting
a more westernized diet, also chimes with the alarming
global increase in obesity in children [35]. e increased
prevalence of obesity in the Libyan population is expected
in light of the increased adoption of poor dietary habits
and sedentary lifestyles [4]. However, comparing the lev-
els of obesity with that reported in other studies should
be approached with caution because of differences in data
collection methods and obesity assessment. Nevertheless,
our findings highlight the urgent need to develop strategies
and policies to tackle obesity among adolescents, especially
since it is expected that sugar intake will increase after the
armed conflict. However, there are some limitations in the
present study which need attention. Firstly, the study is
based on a secondary data analysis, making it impossible
to control the variables used in the primary research. For
example, we cannot rule out several potential risk factors
for obesity, such as birth weight, breastfeeding in the infant
stage, long-term dietary habits, family function, and a fam-
ily history of obesity [3, 4, 36]. In addition, the primary data
were collected using a cross-sectional design that does not
allow for exploring causal relationships [37]. Moreover,
the original sample calculation did not consider the design
effect for clustered sample. Although a multilevel analysis
was conducted considering school clusters, we acknowl-
edge this as a limitation that should be avoided in future
research. erefore, results obtained in this research should
be verified in future studies with more robust methodolo-
gies to inform interventional strategies in the population.
Moreover, the primary research used the WHO criteria,
which assessed caries at the dentin level; hence, the full car-
ies spectrum was not measured. erefore, further studies
are needed using a comprehensive assessment of the dental
caries status of schoolchildren using the International Car-
ies Detection and Assessment System (ICDAS) [38].
Conclusion
e present study found no direct association between
caries and obesity among 12 year-old school children
when the obesity was measured as BAZ and control for
social position and sugar intake. Although obesity and
caries appeared to have no direct relationship, both con-
ditions share common risk factors, which supports apply-
ing a common risk approach to health promotion by
emphasizing efforts to increase awareness about sugar’s
role in obesity and dental caries.
Abbreviations
BMI Body mass index
BAZ BMI-adjusted z-scores for age and gender
DMFT Decay-missing-filled teeth index
ICDAS International Caries Detection and Assessment System
Acknowledgements
The authors would like to express their gratitude for Dr Morenike Folayan
(Department of Child Dental Health, Obafemi Awolowo University, Ile-Ife,
Nigeria) for her role in editing the final draft.
Author contributions
EA: design, data collection analysis, writing up. LB, SE: writing up and review-
ing. AA: design, analysis, writing up and reviewing. All authors read and
approved the final manuscript.
Funding
None.
Availability of data and materials
The datasets used and analyzed during the current study are available from
the corresponding author on reasonable request.
Declarations
Ethics approval and consent to participate
Permission to use the primary data was obtained from the Department of
Dental Public Health at the University of Benghazi. Research Ethics Commit-
tee approved the study at the Faculty of Dentistry, University of Benghazi (Ref
No: UOB-053). Informed consent was obtained from the parent and/or legal
guardian for all the study participants before data collection. Only children
with a signed parental consent and who gave their verbal assent were
included in the study. All methods were carried out in accordance with the
Declaration of Helsinki and relevant guidelines and regulations.
Consent for publication
Not applicable.
Competing interests
The authors declare no competing interests.
Received: 18 August 2022 Accepted: 10 January 2023
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