Table of Contents
What About Our Children?Overweight and Obesity in Oxford County Preschoolers
Table of Contents
Table of Contents����������������������������������������������������������������������������������������� 1Acknowledgements ������������������������������������������������������������������������������������� 2List of Figures and Tables ���������������������������������������������������������������������������� 3Executive Summary������������������������������������������������������������������������������������� 4
Introduction Purpose �������������������������������������������������������������������������������������������� 5 Measurement of Overweight and Obesity ���������������������������������������� 5 DefiningChildhoodObesity �������������������������������������������������������������� 5
Rates of Adult Overweight and ObesityOverall Prevalence in Canada and Ontario �������������������������������������� 6Prevalence in Oxford County Adults ������������������������������������������������� 7
Factors that Influence the Prevalence of Adult ObesityIndividual Risk Factors – Gender, Age, Income ������������������������������� 7
What About Our Children?Parent’s Perception of their Child’s Weight �������������������������������������� 9Childhood Obesity Indicators – Physical Activity and Diet ������������� 10Do Obese Young Children Become Obese Adults? ����������������������� 11At What Age Should We Be Concerned? ��������������������������������������� 12
The Impact of ObesityNon-Communicable Diseases�������������������������������������������������������� 12Social Impact of Obesity ���������������������������������������������������������������� 13Economic Impact of Obesity ���������������������������������������������������������� 13
Prevention StrategiesPrenatal �������������������������������������������������������������������������������������������� 14Infancy ���������������������������������������������������������������������������������������������� 14Preschool Years ������������������������������������������������������������������������������� 14School Age Children ������������������������������������������������������������������������� 15Growth and Weight Status Monitoring ��������������������������������������������� 15Public Health Messaging ������������������������������������������������������������������ 15
Conclusions ������������������������������������������������������������������������������������������� 16
References ��������������������������������������������������������������������������������������������� 17
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Authorship and Acknowledgements
Authorship
Karen Reading, Public Health Nutritionist, Oxford County Public HealthDeborah Carr, Epidemiologist, Oxford County Public Health
Acknowledgements
The authors would like to acknowledge the following Oxford County Public Health staff members for their help and support while producing this document:
• KathrynBocking,DataAnalyst
• LornaBoratto,PublicHealthNurse
• SusanMacIsaac,ManagerHealthPromotion
• AbbyBryan-Pulham,PublicHealthDietitian
• LyndaMetcalfe,SchoolNutritionProgramCoordinator
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List of Figures
1. PercentageofCanadianAdultsOverweight,Obese and Normal Weight from 2009 CanadianCommunityHealthSurvey(2009)
2. PercentageofOntarioAdultsOverweight,Obese and of Normal Weight from 2009 CCHS
3. Percentage of Oxford County Residents (Adults)Overweight,ObeseandofNormalWeightfrom2009CCHS
4. PercentageofAdultCanadians,Ontarions,andOxfordCountyResidentsOverweight,ObeseandNormalWeightfrom2009CCHS
5. PercentageofAdultOxfordCountyResidentsOverweight/ObesebySexfrom2009CCHS
6. Percentage of Oxford County Residents Overweight/ObesebyAgeGroupfrom2009CCHS
7. Percentage of Oxford County Preschool AgedChildrenOverweight/Obese/atRiskofOverweightfrom2007to2010PreschoolHealthFairs(WHO)
8. Percentage of Oxford County Preschool AgedChildrenOverweight/Obese/atRiskofOverweightbyGenderfrom2010PreschoolHealthFair(WHO)
9. PercentageofOxfordCountyPreschoolAgedChildren by Frequency of Time in Front of TV/Computerfrom2010PreschoolHealthFair
10. TheRelationshipbetweenWeightsStatusandMortality
List of Tables
1. WHOCut-OffPointsandTerminologyUsingBMI-for-Age:2to5Years
2. CanadianBMICategoriesandLevelsofHealthRisk(CanadianGuidelinesforBodyWeightClassification inAdults,HealthCanada)
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List of Figures and Tables
Childhood obesity is a major public health problem asobesityisbecomingmoreprevalentinchildren ofallages.Overweightandobesityareconditions influenced by many factors, including nutrition andphysicalactivityhabits,geneticfactorsand an“obesogenic”environmentthatencourages overeatingandsedentarybehavior.
Recentprovincialandnationalweightstatusdata on preschool children is lacking. For this reason, Oxford County Public Health & Emergency Servicesmeasuredtheheightsandweightsofapproximately 2,000 preschool children at Preschool Health Fairs from 2007 to 2010 to determine their weight status.
We found that childhood obesity is occurring earlier thanwethought.In2010,approximately35%ofOxfordCountypreschoolers(ages3to5)werefoundtobeoverweight,obeseandatriskofbeingoverweight.Thisisaconcernbecauseresearchhasshownthatoverweightandobesepreschoolerstendtoremainoverweightandobeseintoadulthood.
Approximately64%ofadultsinOxfordCountywereclassifiedasoverweightorobesein2009,significantlyhigherthanthenationalandprovincialaverages.Thisisofconcernbecauseobesityistheleading cause of chronic health problems for adults. Evenamongchildren,overweightisassociatedwithvariousriskfactorsforthedevelopmentofcardiovasculardiseaseandtype2diabetes.Inadditiontolongtermphysicalhealthissues,overweightchildrenfacesignificantmentalandpsychosocial health issues that are also linked to concurrent health problems.
Reviewsoftheliteraturesuggestthatchildhoodobesitypreventionmust:
• Bemulti-faceted;• Startduringpregnancy;•Haveanemphasisontheearlyyearsandschool agechildren;• Involveparentsandcaregivers;and•Movetowardsmorepolicyandsocialchange.
Topreventstereotypesandchastisingobesechildren, obesitypreventionmessagingshouldfocusonhealth ratherthanmessagesthatemphasizeachievinganidealweight.Itisrecommendedthatpreventioneffortspromote healthyeatingandactiveliving,with an emphasis on:
• Increasingconsumptionofvegetablesandfruit;• Increasingbreastfeedinginitiation,durationand exclusivity;•Decreasingconsumptionofsugar-sweetened beveragesandhigh-energydense,nutrient-poor foods;• Increasingphysicalactivity;and• Decreasing screen time.
PublicHealthfoundthatparentsofoverweightandobesepreschoolersinOxfordCountydonotperceivetheirchildassuch.Thismayhaveasignificantimpactonpreventioneffortsasparentsmustbeawarethattheirchildisoverweight,andconcernedaboutthehealth and mental consequences, before they are able toeffectivelyparticipateinpreventionprograms.
HealthprofessionalscanhelpbyimprovingrecognitionofchildhoodoverweightbyusingtheWHO(WorldHealthOrganization)growthchartsto screen and monitor children’s weight as part of routinepractice.Healthprofessionalscanalsoprovideanobjectivemeasureofweightstatusandstartaconversationabouteatinghabitsandphysicalactivitypatterns.
We found that childhood obesity is occurring earlier than we thought… This is a concern because research has shown that children who are overweight and obese as preschoolers tend to remain overweight and obese into adulthood.
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Executive Summary
Introduction Purpose
ThemainpurposeofthisreportistoprovidelocalprevalenceratesofoverweightandobesityamongOxford County preschool children, based on direct measurements of their height and weight from 2007 to 2010. This data will assist Public Health in establishing baseline information that can be used tomonitorchangesandevaluatetheeffectiveness ofpreventionprogramsinourcommunity.
Thisreportalsocomparestheratesofoverweight andobesityamongadultslivinginCanada,Ontario andOxfordCounty,andprovidesasnapshotofthe risk factors that impact the weight status of Oxford children.Thereisaconsensusthatmostoverweight and obese children become obese adults, highlighting theneedtomakepreventionofunhealthyweights
apublichealthpriority.Thisreportalsoprovidesa summary of recommended strategies for the preventionofchildhoodobesity.
Measurement of Overweight and Obesity In Adults
Bodymassindex(BMI)istheacceptedmeasureforoverweightandobesityinadults18yearsandover.BMIisanindirectmeasureofobesitybasedonmeasuresofheightandweight[wt(kg)/ht(m)2],whicharenon-invasiveandinexpensivetoconduct.
ABMIof25-29.9isclassifiedasoverweightanda BMIgreaterthan30isclassifiedasobese.Althoughhighlyspecific,BMIisanon-sensitiveindicatorof obesity and, therefore, should only be used as a screening tool, not as a diagnostic tool. For assessinghealthriskassociatedwithoverweightstatus,BMIshouldbeusedincombinationwithwaistcircumferenceasBMIalonedoesnottakeintoaccount body composition and fat distribution.
Defining Childhood Obesity
Itismuchmorechallengingtorecognizeoverweightand obesity among children and youth because body composition, weight and height change dramatically with normal growth and maturation. Thus, growth chartsareusedasageandgender-specificthresholds
There is a consensus that most overweight and obese children become obese adults, highlighting the need to make prevention of unhealthy weights a public health priority.
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ObesityisanoverallprobleminOxfordCounty,affectingallages.Ifwearetobesuccessfulinour battle against obesity and reducing Ontario’s escalating healthcarecost,preventioneffortsmusttargetallagesin multiple settings and start at an early age.
Obesity is a societal issue, one in which we can all play aroleinpreventing.Whilethisreportwaspreparedby health professionals primarily for use by other health professionals, we hope parents will also find this information helpful.
are required to classify adiposity status correctly in children and adolescents.
Childhood obesity is defined by calculating the child’sBMIandplottingitonageandgenderspecific growth charts. There are many growth chartsdevelopedforthispurpose.MoststudieshaveusedUSgrowthchartsfromtheCentreforDiseaseControl.However,arecentcollaborativestatementreleased in February 2010 from the Dietitians of Canada,CanadianPediatricSociety,CollegeofFamily Physicians of Canada and Community Health Nurses of Canada recommend the use of the2006WorldHealthOrganization’s(WHO)growth standards to monitor the growth of all CanadianchildrenfrombirthtofiveyearsandtheWHOReference2007GrowthChartsbeusedforall children and youth between the ages of 5 to 19 years.
The new WHO international growth standards are basedonover8,000childrenfromsixcountriesaround the world. These children were raised according to the most current Canadian nutrition recommendations and health practices, including exclusivebreastfeedingforthefirstfourtosixmonths of life. The WHO growth charts are recommended to monitor growth of Canadians because they concluded that children of all ethnic backgroundshavesimilarpotentialforgrowth,as there were minimal differences in growth rates between the different countries.
Oxford County Public Health chose to use the WHO growth charts to assess the weight status of Oxford’s preschoolers because they are growth standards and depict how children should grow. TheWHOgrowthstandardsalsoserveasagoalor
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prescription for all healthy Canadian children to achieve,regardlessofethnicity,socioeconomicstatusand type of feeding.
Inaddition,theCollaborativeStatementonChildGrowthinCanada,2010,hassuggestedthattheWHOGrowthstandardsbeusedforthepurposesofpopulationhealthsurveillanceinordertocapturechildrenclassifiedasunderweight,overweightorobese.AccordingtotheWHOgrowthcharts,children(2to5years)whohaveaBMI-for-age>97thpercentileareclassifiedasoverweightandthosewithaBMI-for-age>99.9thpercentileareclassifiedasobese(Table1).
Rates of Adult Overweight and Obesity Overall Prevalence in Canada and Ontario
Forthepastseveralyears,theprevalenceofobesityhassteadilyincreasedthroughoutCanada(PublicHealthAgencyofCanada2009).Figure1showsthemostrecentnationalBMIestimates.In2009,33.7%ofCanadiansreportedBMIsclassifiedasoverweightandanadditional17.9%reportedBMIsclassifiedasobese.SimilarestimateswerereportedforOntarioresidents(Figure2).In2009,34.0%ofOntarioresidentsreportedBMIsclassifiedasoverweightandanadditional17.4%reportedBMIsclassified as obese. This shows that as a whole, the proportionofresidentsthatareoverweightorobeseinOntarioiscomparabletothenationalaverage.
Table 1: WHO Cut-Off Points and Terminology Using BMI -for-age: 2 to 5 Years
Weight Status Percentile
Risk of Overweight > 85th percentileOverweight > 97th percentileObese > 99.9th percentile
Figure 1: Percentage of Canadian Adults Overweight, Obese and of Normal Weight from 2009 Canadian Community Health Survey (CCHS)*Data Source: 2009 CCHS Cansim Table 105-0501
48.4%
33.7%
17.4%
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Normal ObeseOverweight BMI Category
Factors that Influence the Prevalence of Adult Obesity Individual Risk Factors – Gender, Age, Income
Individualfactors,suchassex,age,andincomehavebeenshowntoinfluencetheprevalenceofobesityinpopulations(Babeyetal.2010,Huotetal.2004,Liuetal.2010,Luoetal.2007).Malestendtoreportahigherprevalenceofobesitythanfemalesinallagecategories(Huot2004,PublicHealthAgencyofCanada2009).InOxfordCountyin2009,65.1%ofmaleresidentsreportedBMIsclassifiedasobeseoroverweight(Figure5),whichisconsistentwiththeprovincialaverage.Forthesameperiod,62.4%offemaleresidentsinOxfordreportedBMIsclassifiedasobeseoroverweight,whichissignificantlyhigherthantheprovincialaveragefor
This data also shows that at least half of Oxford residents in all age groups are overweight or obese, and that the proportion of overweight or obese residents observed in the 45-64 years age group is significantly higher than the provincial average.
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Prevalence in Oxford County Adults
ThedistributionofBMIsintheOxfordCountypopulation does not resemble distributions for OntarioandCanada,asawhole.In2009,39.2%ofOxfordresidentsreportedBMIsclassifiedasoverweightandanadditional24.6%reported BMIsclassifiedasobese(Figure3).Thismeansthat63.8%ofOxfordresidentsareoverweightorobese. This proportion is significantly higher than thenationalandprovincialaverages(Figure4),suggestingthatprogramsandservicesinOxfordshould be augmented to assist residents in achievinghealthyweights.
Figure 4: Percentage of Canadian Adults, Ontarians, and Oxford County Residents Overweight, Obese and of Normal Weight from 2009 CCHS*Data Source: 2009 CCHS Cansim Table 105-0501
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Normal
Oxford Ontario Canada
ObeseOverweight BMI Category
36.2%39.2%
24.6%
48.6%
34%
17.4%
48.4%
33.7%
17.9%
Figure 3: Percentage of Oxford County Adult ResidentsOverweight, Obese and of Normal Weight from 2009 CCHS�*Data Source: 2009 CCHS Cansim Table 105-0501
0%
5%
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45%
Normal ObeseOverweight BMI Category
36.2%
39.2%
24.6%
Figure 2: Percentage of Ontarian Adults Overweight, Obese and of Normal Weight from 2009 CCHS*Data Source: 2009 CCHS Cansim Table 105-0501
48.6%
34%
17.4%
0%10%
20%
30%
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60%
Normal ObeseOverweight BMI Category
In 2010, 34.6% of Oxford County preschoolers were obese, overweight, or at risk for becoming overweight.
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Figure 6: Percentage of Oxford County Residents Overweight/Obese by Age Group from 2009 CCHS*Data Source: 2009 CCHS Cansim Table 105-0501
0%
51.3%57.3%
75.6%
62.1%
50.7%
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12 to 19 20 to 34 35 to 44 45 to 64 Over65
Age Group
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Figure 5: Percentage of Adult Oxford County Residents Overweight/Obese by Sex from 2009 CCHS*Data Source: 2009 CCHS Cansim Table 105-0501
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65.1% 62.4%
females. This is proof once again that females in Oxfordareathigherriskforbeingoverweightorobesethantheirprovincialcounterparts.Therefore,interventionsdesignedtocontrolobesityarewarrantedinOxfordandshouldrequireagender-specific component.
InCanada,increasingprevalenceofobesityhas beenobservedinallagegroups(Luo2007).Figure 6 shows the proportion of Oxford residents reportingaBMIclassifiedasoverweightorobeseacrossagegroupings.In2009,51.3%ofOxfordresidentsage20-34years;57.3%ofresidentsage35-44years;75.6%ofresidentsage45-64years;and62.1%ofresidentsage65yearsandoverreportedBMIsclassifiedasobeseoroverweight.
Thesedatarevealanumberofage-relatedtrendsoccurring in Oxford County. These data show that the proportion of residents classified as obese or overweightinOxfordCountysignificantlyincreaseswithage(P<0.0001),whichisconsistentwiththeliterature(Liuetal.2010).Thesedataalsoshowthatat least half of Oxford residents in all age groups areoverweightorobese,andthattheproportionofoverweightorobeseresidentsobservedinthe45-64 years age group is significantly higher than the provincialaverage.ThisillustratesthatobesityisanoverallprobleminOxfordwarrantinginterventionthroughoutallagegroupings,butthatinterventionsoffered must include a focus on or be increasingly accessibletoresidents45-64yearsofage.Ithasbeen shown that the risk of obesity increases with decreasinghouseholdincome(Babey2010,Kim&Leigh2010),markinganinverserelationship.This association was explored in Oxford County usingthe2007/2008CanadianCommunityHealthSurvey(CCHS)becauseincomeisawell-establisheddeterminant of health.
Canadians are living in a fast-paced society…raising a family and running a household make it difficult to find the time to grocery shop, prepare well balanced meals, as well as find time for physical activity.
Task Force references to define weight status and foundthat21%ofpreschoolers(age2to5)wereclassifiedasoverweightand/orobeseandofthose15%wereclassifiedasoverweightand6%wereobese.Whencomparingprevalencedataforchildren, one needs to be aware that they may be somewhatvariableduetoanumberofdifferentmethods for assessing childhood obesity.
Parents’ Perception of their Child’s Weight
In2010,OxfordCountyPublicHealthmeasuredparents’ perception of their children’s weight at thepreschoolhealthfairsusingtheNutriStep®screeningtool.34.6%(n=243)ofthechildrenat the preschool health fair were classified as overweight/obese/atriskofoverweight,yetlessthan1%oftheparentsreportedthattheywereconcernedthattheirchildwasoverweight.33.1%ofthepreschoolers parents felt that their child was “about the right weight,” when in fact their childwasclassifiedasoverweight/obese/atrisk ofoverweight.
Our findings are consistent with the findings of others:thatparentsdonotperceivetheirchildrenasbeingoverweightordifferentthantheirpeers(Campbelletal.,2006,Baughcumetal.,2000,Carnelletal.,2005).Ithasbeensuggested
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Asignificantassociationwasnotdetectedbetweenobesity and income in Oxford County. Results of thesameanalysisusingnationalleveldatarevealed thattheprevalenceofobesityisloweramonghigherincome females, but that this relationship does not exist for males. Future exploration may be required to determine if this trend exists in Oxford County.
What About Our Children?
Ithasalreadybeenestablishedthattheriskof beingoverweightorobeseincreaseswithage andthatoverhalfofalladultOxfordCounty residentsineveryagecategoryisoverweight orobese.Inthisenvironment,howareour children doing?
Since2007,OxfordCountyPublicHealthhasscreened more than 2,000 children between theageofthreetofiveyearswhoattendtheannualpre-schoolhealthfair.Theirweightstatuswas determined by measuring their height and weight andplottingtheirBMI-for-ageontheWHOgenderspecific growth charts.
In2010(Figure7),screeningsshowedthat 34.6%ofOxfordCountypreschoolerswereobese,overweight,oratriskforbecomingoverweight.Since2007,thisproportionhasgradually increased, with the exception of a slight decrease in 2009, suggesting that the risk of obesity among preschoolers may be getting worse. The proportion of preschoolers identified asobese,overweight,oratriskofbecomingoverweightwasalsosignificantlyhigherformales (p=0.0407)(Figure8),demonstratingthat gender-specificprogrammingandmessaging may be required.
Itshouldbenotedthatrecentprovincialandnational data on preschool age children is lacking. In2004,theCCHSusedtheInternationalObesity
There is a strong association between overweight, obesity and screen time.
0%
34.7%33.3%
34.6%
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2007 2008 2009 2010
Year
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Figure 7: Percentage of Oxford County Preschool Aged Children Overweight/Obese/At Risk of Overweight from 2007 to 2010 Preschool Health Fairs (WHO)*Data Source: Oxford County Public Health Preschool Health Fair, 2007-2010
Childhood Obesity Indicators – Physical Activity and Diet
Weight gain results from an imbalance of energy intake and energy expenditure: when energy intake exceedsenergyexpenditure.Societalchangeshaveresulted in a decrease in energy expenditure as physicalactivitylevelshavedeclined,alongwithacorresponding increase in caloric intake.
Canadians and other industrialized countries around theworldarelivinginan“obesogenic”environment.Suchanenvironmentpromotesthedevelopmentofunhealthy weights as there is an increased reliance on vehiclesfortransportation,timesavinggadgetsinthehome, and mechanical and computerized technology in the workforce, all of which contribute to a decrease in energy expenditure.
Canadiansarelivinginafast-pacedsociety,oneinwhich it is the norm for both parents to work outside the home. Working outside the home, raising a family and running a household make it difficult to find the time to grocery shop, prepare well balanced meals, as wellasfindtimeforphysicalactivity.
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thattherisingprevalenceofobesitymayhavenormalized the condition so that parents can no longerrecognizethattheirownchildisoverweight(Campbelletal.,2006).Ifparentsdonotperceivethatthereisaproblem,itmayhavesignificantimplicationsforpublichealthinterventions.
Researchers point to different reasons as to why youth are more sedentary now than 20 years ago. Someofthefactorsidentifiedinclude:• safetyconcerns(traffic,urbanization,outside playtime)• childrenbeingdriventoschool• budget restraints in schools limiting daily physical education classes• limited funding of community programs• liability, cost and insurance issues in schoolsthatlimitafter-hoursuseoffacilitiesby communities• and increased technology, which has increased screentime(Bar-OrO,1998).
TheCanadianSocietyforExercisePhysiology(CSEP)recentlyrevisedtheCanadianPhysicalActivityGuidelinesin2011torecommendaminimumof60minutesofmoderate-tovigorous-intensityactivityperdayforchildrenage5to11(Tremblayetal,2011).Thisrecommendationincludesvigorous-intensityactivitiesatleast threedaysperweekandactivitiesthatstrengthenmuscle and bone at least three days per week.
AccordingtotheCanadianHealthMeasuresSurvey2007-2009,only7%ofCanadianchildrenandyoutharemeetingtheserecommendations(Colleyetal.,2011).Theseresultsaremuchmorevalidthanpreviousself-reportedphysicalactivityinchildren,asthissurveyusedmeasuredvaluesusingaccelerometers.Thissurveyalsofoundthatboysandgirlsaresedentaryabout8.5hoursaday.CSEPrecentlyreleasedsedentarybehaviorguidelineswhich
0%
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MaleSex
Female
38.1%30.7%
Figure 8: Percentage of Oxford County Preschool Aged Children Overweight/Obese/at Risk for Overweight by Gender from 2010 Preschool Health Fair (WHO)*Data Source: Oxford County Public Health Preschool Health Fair, 2007-2010
Per
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age
Ove
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recommend limiting recreational screen time to no more than two hours per day for children between the ages 5 to 17 for health benefits, while also limiting sedentary transport, prolonged sitting and time spent indoors throughout the day (CSEP2011).
Thereisastrongassociationbetweenoverweight,obesityandscreentime.Thirty-fivepercentofCanadian youth who spend 30 or more hours per weekinfrontofascreenareoverweightorobese,comparedto23%ofthosewhospendfewerthan10hoursperweekinfrontofascreen(Sheilds,2005).TheCanadianPediatricSocietyandCSEPrecommendlimitingTVviewingtolessthan2hoursperdayforschoolagedchildren.Yet,accordingtotheNationalLongitudinalSurveyofChildrenandYouth2004-2005,27%oftwotothreeyearoldsand22%offourtofiveyearoldareexposed to more than two hours of screen time per day,andtheaverageCanadianyouthaccumulatessixhoursofscreentimeinweekdaysandoversevenhoursonweekenddays(Boyce,2008).
How do Oxford children compare? Public Health administered a questionnaire to parents at the preschool health fairs that asked parents the number ofhourstheirchildspentwatchingtelevision.Seventy-sixpercentofOxfordpreschoolerswatchTV two hours or less per day and approximately 24%watchthreeormorehoursofTVperday(Figure9).Itshouldbenotedthatthiswasaself-administeredsurvey,sothesenumbersmaybeanunderestimationofactualviewingtime.
NotonlydoesTVviewingpromoteweightgainbydisplacingphysicalactivity,itoftenleadstoanincreasedenergyintakeaschildrenseemtopassivelyconsumeexcessiveamountsofenergy-densefoodswhilewatchingtelevision.
Children are also being targeted by food manufacturers promoting unhealthy food while watchingTV.Advertisingtargetingchildrenisdominatedbyfiveproductcategories:softdrinks,pre-sugaredcereals,confectionary,snacksandfast-foodrestaurants(CPS,2003).Researchhasshown that children between the ages of two andfivecannotdifferentiatebetweenregularTVprogramming and children under eight years ofagecannotdistinguishbetweenadvertising,makingthemparticularlyvulnerabletomisleadingadvertising(CPS,2003).Parentsofyoungchildrenhaveanimportantroletoplayinprotectingtheirkidsfrominvasivemarketing,andineducatingthemaboutadvertisingstartingfromanearlyage.
Do Obese Young Children Become Obese Adults?
Manystudiespublishedinthelastdecadedemonstrate a strong relationship between weight statusinchildhoodandeventualadultobesity(Fieldet al., 2005, Viner et al., 2005, Whitaker et al., 1997).Itisestimatedthatoverweighttwotofiveyear-oldchildrenarefourtimesmorelikelythantheirhealthy-weightpeerstobecomeoverweightasadults(Freedmanetal.,2005)andchildrenwhoareobesehavebeenfoundtohavea25%to50%increasedriskofbeingobeseasadults(Guoetal.,2000).
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Overweight and obesity in the early years predicts overweight in later life. Specifically, children who become obese before the age of six are likely to be obese later in childhood.
Figure 9: Percentage of Oxford County Preschool Aged Children by Frequency of time in front of TV/Computer from 2010 Preschool Health Fair�*Data Source: Oxford County Public Health Preschool Health Fair, 2010
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76.2%
23.8%
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At what age should we be concerned?
Atonetimehealthprofessionalsbelievedthatmostoverweighttoddlersandpreschoolerswouldgrowintotheirexcessweight.However,thisisnotthecasetoday.Ithasbeenestablishedthatoverweightandobesityintheearlyyearspredictsoverweightinlaterlife.Specifically,childrenwhobecomeobesebefore the age of six are likely to be obese later in childhood(Quattrinetal.,2005).
Severalobservationalstudiessuggestthatanearlyadiposity rebound may be an important predictor ofadultobesity(Rolandetal.,1994,Dietz1994,Whitakeretal,1998).Theadiposityrebound occurs when the child’s excess fat tissue declines to itslowestlevelandthenbeginstoincreaseasthe child grows. The adiposity rebound has been documented to occur between the ages of 4 to 6 yearsofage(DietzandRobinson2005,Whitakeretal.,1998,Rolland-Cacheraetal.,1984,2002).Itis thought that an early “adiposity” rebound, before ages 4 to 6, is associated with obesity in adulthood (Rolandetal.,1994,Dietz1994,Whitakeretal,1998).
Naderetal.,(2006)followedapproximately1400childrenlongitudinallyover13yearsandfoundthatchildrenwhowereoverweightatmorethanone time at ages 24, 36, or 54 months during the preschoolperiodweremorethanfivetimesaslikelytobeoverweightatage12thanthosewhowereata normal weight at all three of the preschool ages. Similarly,Margareyetal.,2003foundthatthemajority(82%)ofchildrenwhowereoverweightattwoyearsofagewerealsooverweightatagetwenty.
Anotherstudyfoundthatbeingintheupperhalfof the normal weight range was a good predictor of overweightorhypertensiveasayoungadult(Fieldetal.,2005).
Others suggest that the parent’s weight status is the best predictor of adult obesity in children under three years of age and that unless one or bothparentsareobese,overweightyoungchildrenare unlikely to become obese adults. Whereas, for childrenoverthreeyearsofage,boththechild’sand the parent’s weight status are equally important predictorsofadultobesity.Asthechildages,theirweight status then becomes the best predictor and this effect was found to be most pronounced in children that were older than 10 years of age (Whittakeretal.,1997).Thesestudiesshowtheinfluenceofthefamilyenvironmentandtheimportanceofpromotinghealthyeatingandactivelivingfortheentirefamilybeginningatanearlyage.
The Impact of ObesityNon-Communicable Diseases
Overweightandobesityinadulthoodhasasignificant effect on life expectancy and premature death.HealthriskincreaseswithBMI’sabove24.9;thehighertheBMI,thegreaterthelevelofhealthrisk(Table2).
Theriskofdyingfromobesity-relateddiseasesincreasesproportionatelywithincreasingBMI(Figure10).InCanada,prevalencedatafromsixcross-sectionalnationalsurveysbetween1985and2000revealedthatoverthe15-yearperiod,morethan57,000deathsamong20-64yearoldswereattributedtooverweightandobesity(Katzmarzyk2000).Comparedtonormalweightindividualswithnohistoryofsmokingorheavydrinking,obesityisassociatedwitha67%increaseinself-reported chronic conditions such as diabetes, hypertension, asthma, heart disease and cancer (Sturmetal.,2001,Sturm2002).
Children are not immune to the health consequences ofexcessbodyweight.Aswithadults,obesityin children is associated with hypertension, dyslipidemia, andahigherprevalenceoftype2diabetes(WHO,2008).DatafromtheBogalusaHeartStudyshowed
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Social Impact of Obesity
Weight discrimination has increased substantially overthelastdecadeandisnowcomparabletoprevalenceratesofracialdiscrimination(Puhl,2010).Thepsychologicalconsequencesofsocialbias on people who are obese include body image dissatisfaction, poor self esteem, depression and disorderedeating(Puhletal.,2009).Thereisalsoevidenceofdiscriminationagainstpeoplewhoare obese reported in educational institutions, employment and in the practices of health professionals(Stunkardetal.1995).Suchweightbiaseshavebeenreportedtocontributetoreducedaccess to social, educational and professional opportunities(Puhletal.2009).
Reviewsofchildhoodobesitysuggestthatmanychildrenandadolescentswhoareoverweightandobese are discriminated against by their peers, whichhasanegativeimpactontheiremotionaldevelopment.Studiessuggestthatadolescentgirlsand boys who are obese are more likely to report emotional disturbance such as poor self esteem and a poor body image as well as difficulties in school thantheirnon-obesecounterparts(Falkneretal.2001,Eisenbergetal.,2003).InoneCanadianschool-basedstudyof12yearolds,lowerself esteemwasnotedamongstudentswithaBMIclassificationofobesity(Tremblayetal.2000)
Economic Cost of Obesity in Canada
In2001,Canada’seconomicburdenintermsofadultoverweightandobesitywasestimatedat4.3billiondollars(1.8billiondollarsindirectcostsand2.5billioninindirectcosts)(Katzmarzyk,2004).Thisreportsuggeststhattheoverallcostofoverweightandobesityisunderestimatedasitonlyincludesthecostsforthosewhoareoverweight,butnotobese.Italsoincludesthecostsofonlyeightchronicdiseasesassociatedwithoverweightadults. Health care costs are spiraling out of control. In2007,healthcarecostsmadeup42%oftheOntariogovernment’stotalspendingprogram.Thisnumber is expected to rise due to Ontario’s aging population and the rising concerns of obesity in youngergenerations(OntarioMinistryofFinance2007).
13
15 20 3025 35 40
Mor
talit
y
Body Mass Index
Figure 10: The Relationship Between Weight Status and Mortality
Diagram source: Sizer, Whitney, Piché, with contributions from A� C� Garcia, (2009)� Nutrition: Concepts and Controversies (First Canadian Edition)� Nelson Education Inc� Toronto, ON
BMI Category Level of Risk
< 18.5 Underweight Increased Risk18.5 - 24.9 Normal Weight Least Risk25.0 – 29.9 Overweight Increased Risk30 and over Obese High Risk30.0 – 34.9 Obese Class I High Risk35.0 – 39.9 Obese Class II Very High Risk≥ 40.0 Obese Class III Extremely High Risk
Table 2: Canadian BMI Categories and Levels of Health Risk
Source: Canadian Guidelines for Body Weight ClassificationinAdults,HealthCanada
thatapproximately60%ofoverweight5to10-yearoldchildrenhadonecardiovascularriskfactorsuchashighbloodpressure,hyperlipidemiaorelevatedinsulinlevels,andover20%ofthesechildrenhadtwoormorecardiovascularriskfactors(Freedmanetal.,1999).Respiratoryproblemssuchasasthmaand sleep apnea are more common in obese children thannon-obesechildren.
Prevention Strategies
Mostofoureffortsatpreventingchildhoodobesityhavefocusedonschoolagechildrenbut,obviously,one’searlyfamilylifeandenvironmentplayanimportantroleinthedevelopmentofobesity.Bythe time Oxford children are between the ages of 3 and5yearsofage,approximately35%arealreadyoverweight,obeseandatriskofbeingoverweight.This is a concern as research has shown that obese preschoolersdonotgrowoutoftheiroverweightstatus.
Someexpertshavesuggestedthatobesitypreventionstrategies should emphasize increased physical activityratherthandietbecauseofthepotentialtoput children on inappropriate weight reducing diets andpromoteinappropriateeatingpatternsand/ordisorders.However,energyoutputisjustonepart of the energy balance equation and we need to continuetofocusongoodnutritionandpositiveeatingexperiencesearlyinlifeasthereisevidencethat they shape dietary preferences and may affect the quality of nutrition throughout childhood.
Itiswellestablishedthatparentsandcaregivershavea profound influence on both the nutritional and physicalactivityhabitsofchildrenduringtheearlyyears. Research has shown that children of parents whoarephysicallyactivearefivetosixtimesmorelikelytobeactivethanthosewithinactiveparents(Kohletal.,1998).Althoughtherearefewstudiesofobesitypreventioninyoungchildren,programswithparentalinvolvementhavebeenfoundtobemoresuccessful(Epsteinetal.,1990,Golanetal.,1998).
Prenatal
Expertshaverecommendedstartingobesitypreventionstrategiesevenbeforethechildisbornasagrowingbodyofevidencesuggeststhattheprenatalenvironmentplaysanimportantroleinthedevelopmentofobesity.Bothnutritionalsurplusand deficiency during the early stages of fetal developmentmaybringaboutobesitylaterinlife(Popkin,2001,Barker,1998).Intrauterinegrowthand growth in the first year of life are predictors for thedevelopmentofadultobesity,cardiovascular
diseaseanddiabetes(Popkin2001,Hoetetal,1999).Childrenborntomotherswhoareobeseduringpregnancyhaveamuchgreaterlikelihoodofbecomingobese(Whitaker,2004).Therefore,recommendationsforobesitypreventionduringtheperinatal stage include good prenatal nutrition and healthcare;avoidingexcessivematernalweightgain;educationaboutbreastfeeding;controllingdiabetes;and helping mothers to lose weight postpartum.
Infancy
Althoughtherearefewprovenobesitypreventionstrategies for young children, the promotion of breastfeedingandimprovinginfantandtoddlerdietsarecitedmostoftenasbeingbestpractice.Preventionof childhood obesity begins in infancy with the establishmentofapositivefeedingrelationshipbetween the parents and the infant. To do so, parents must learn the infant’s hunger and satiety cues and respondbyprovidingfoodsthataredevelopmentallyandnutritonallyappropriate(Satter,1987).Inameta-analysisof29studies,breastfeedingwasfoundtoprotectagainstobesityinlaterlife(Owenetal.,2005),whereasformulafeedingisassociatedwithmore rapid weight gain in early infancy and an increased risk of obesity in childhood and adolescence (Dewey,2001,Bakeretal.,2004).
Breastfeedingmayplayaprotectiveroleinthelaterdevelopmentofobesityasbreastfedinfantsmaylearntoself-regulateenergyintakebetterthanformula-fedinfants,andtheyhavebeenfoundtoadaptmorereadilytonewfoodssuchasvegetables(Birch&Fisher,1998).Foroptimalgrowth,HealthCanada(2004)recommendsexclusivebreastfeedingforthe first six months of life with the introduction of nutrient-rich,solidfoods,withparticularattentiontoiron at six months and continued breastfeeding for up to two years and beyond.
Preschool Years
Toddlers and preschoolers are eager to learn and are greatlyinfluencedbytheirparents;therefore,parentalrolemodelingofappropriatefoodchoicesandactivelivingarerecommendedstrategiesforthepreventionofchildhoodobesity.Manynutritionexpertssuggestthat dietary habits are mostly established by age four.
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Researchersbelievethatifvarietyisnotintroducedduringthistime,life-longaversiontocertainfoodsmaydevelop(Birch,1999).Othershavesuggestedthatthetype of food consumed as part of the child’s regular dietmayhaveagreaterimpactonthedevelopmentofchildhoodobesitythanmerelyovereating.
The2006CanadianClinicalPracticeGuidelinesontheManagementandPreventionofObesityinAdultsandChildrenrecommendsthatchildhoodpreventionefforts include programs in multiple settings that targetbehaviorchangeandhaveparentalandfamilyinvolvement.Behaviourchangestrategiesincludeprovidingabalanceddiet;limitingconsumptionofenergy-densesnacksandbeverages;limitingscreentimetoencouragemoreactivityandlessfoodconsumption,andlimitingexposuretofoodadvertising.
School Age Children
Theschoolenvironmenthasaprofoundinfluenceonchildren’sattitudes,preferencesandbehaviours,andit offers a formal setting for children to acquire health knowledge and skills. For this reason, schools are often citedasapivotalsettingforthepromotionofhealthyeatingandactiveliving.
Schoolfoodpoliciesanduniversalnutritionprogramsplay an important role in promoting healthy eating as a third of a child’s food intake is consumed at school. Interventionsandpoliciestoincreasedailyphysicalactivitythroughphysicaleducationclasstimeandopportunitiesforactiverecreationalsoplayavitalrole.Forschool-basedobesitypreventionprogramstobeeffective,itisrecommendedtheyinvolveallchildreninaschool,targetthewholeschoolenvironment,andthattheyarebehaviourallyfocused.Theyshouldalsobelong-lasting,multi-facetedandsustainable(Warrenetal.,2003).
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Growth and Weight Status Monitoring
TheCollaborativeStatementongrowth(2010)recommends that Canadian children be routinely screenedforhealthygrowthanddevelopmentusingtheWHOGrowthStandards.Thisallowsforearlyidentificationofat-riskchildrensopromptinterventionscanbeintroduced.Monitoringgrowthprovideshealthprofessionalswithanopportunitytodiscuss breastfeeding for infants and healthy eating andactivelivingwiththechild’scaregivers.Whenagrowthproblemoccurs,counsellingprovidedtoparentsshouldbesensitive,positive,non-judgmentalandavoidinstillingfeelingsofguilt.Thefocusofhealth education and counseling should be on health ratherthanonweightandappearance(CollaborativeStatementonGrowth,2010).
Public Health Messaging
Topreventstereotypesandchastisingofobesechildren,publichealthmessagingandpreventionprogramsshouldfocusonhealthtomotivatebehavior changeratherthanmessagesthatemphasizeachievinganidealweight.Inotherwords,publichealthmessaging should be health focused and promote healthy eating andactivelivingforallchildrenregardlessoftheirweight status.
The2006CanadianClinicalPracticeGuidelinesontheManagementandPreventionofObesityinAdultsandChildrenrecommendsthatpreventioneffortsfocusontargetbehaviours.Thesebehavioursinclude:
• thediscussionofthepreventionofchildhood obesitywiththepregnantmother;• increasing breastfeeding initiation, duration andexclusivity;• increasingconsumptionofvegetablesandfruit;• increasingphysicalactivity;• limitingconsumptionofenergy-densesnack foodsandbeverages;• limiting screen time to no more than twohoursadaytoencouragemoreactivity and less food consumption and to limit exposuretofoodadvertising;and• working with schools to promote healthy eatingandactiveliving.
Lastly,the2006CanadianClinicalPracticeGuidelinesontheManagementandPreventionofObesityinAdultsandChildrenrecommendsobesitypreventioneffortsexpandbeyondeducationalcampaignsfocusedonindividualbehavioursandmovetowardslarger-scalepoliciesthat initiate societal changes. For example, if people donothaveadequateresourcestoaccessaffordablehealthyfoods,itistoodifficulttoexpectindividualactions to be successful.
Conclusions
Childhood obesity is a growing public health concern with causes that are complex and multifactorial.Itisassociatedwithnumeroushealth problems and is often resistant to treatment. Therefore,preventionisahighpriority.
Since35%ofOxfordCountypreschoolersarealreadyclassifiedasoverweight,obeseandatriskofoverweight,preventionmuststartearly.Thereisastrong association between parent weight status and theirchild’sweightstatus.Approximately64%ofOxfordadultswereclassifiedasoverweightorobesein 2009 and of those of childbearing age, more than50%wereclassifiedasoverweightorobese.Thisillustratesthatobesityisanoverallproblemin
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Oxfordwarrantinginterventionthroughoutallages.
Parentshaveaprofoundinfluenceonchildrenandcanplayapositiveroleinestablishinghealthyeatingandphysicalactivity.WehavefoundthatOxford County parents of preschoolers do not perceivetheirchildrenasoverweight.Thisisaconcernandmayhavesignificantimplicationsforpublichealthpreventionefforts.
HealthprofessionalscanhelpimproverecognitionofchildhoodoverweightbyusingtheWHOgrowth charts to screen and monitor children’s weight as part of routine practice. Health professionalscanusethisopportunitytoprovideanobjectivemeasureofweightstatus,reassureanxiousparents,andstartaconversationwiththeparentsabouteatinghabitsandphysicalactivitypatterns.
Preventioneffortsshouldhaveanemphasisontheearlyyears,bemulti-faceted,involveparentsandcaregivers,andmovetowardspolicyandsocial change. Childhood obesity is a societal issue;everyonehasaroletoplayinthepreventionof childhood obesity and, if successful, we can help reduce the rates of adult obesity and their associated health care costs.
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