Effect of Six-Month Diet Intervention on Sleep among Overweight and Obese Men with Chronic

15 Pages·2016·1.1 MB·English

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Tan, Xiao; Alén, Markku; Wang, Kun; Tenhunen, Jarkko; Wiklund, Petri; Partinen,
Author(s):
Markku; Cheng, Sulin

Title: Effect of Six-Month Diet Intervention on Sleep among Overweight and Obese Men
with Chronic Insomnia Symptoms : A Randomized Controlled Trial

Year: 2016
Version:

Please cite the original version:
Tan, X., Alén, M., Wang, K., Tenhunen, J., Wiklund, P., Partinen, M., & Cheng, S.

(2016). Effect of Six-Month Diet Intervention on Sleep among Overweight and Obese
Men with Chronic Insomnia Symptoms : A Randomized Controlled Trial. Nutrients,

8(11), 751. https://doi.org/10.3390/nu8110751

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nutrients
Article
Effect of Six-Month Diet Intervention on Sleep
among Overweight and Obese Men with Chronic
Insomnia Symptoms: A Randomized Controlled Trial
XiaoTan1,2,MarkkuAlén2,3,KunWang1,JarkkoTenhunen2,PetriWiklund1,2,
MarkkuPartinen4andSulinCheng1,2,*
1 ExerciseHealthandTechnologyCenter,ShanghaiJiaoTongUniversity,Shanghai200240,China;
xiao.tan@jyu.fi(X.T.);[email protected](K.W.);petri.wiklund@jyu.fi(P.W.)
2 DepartmentofHealthSciences,UniversityofJyväskylä,Jyväskylä40014,Finland;
markku.alen@jyu.fi(M.A.);[email protected](J.T.)
3 DepartmentofMedicalRehabilitation,OuluUniversityHospitalandCenterforLifeCourseHealthResearch,
UniversityofOulu,Oulu90220,Finland
4 VitalMedResearchCenter,HelsinkiSleepClinicandDepartmentofNeurosciences,UniversityofHelsinki,
Helsinki00380,Finland;markku.partinen@helsinki.fi
* Correspondence:sulin.cheng@jyu.fi;Tel.:[phone];Fax:[phone]
Received:14September2016;Accepted:16November2016;Published:23November2016
Abstract: Growing evidence suggests that diet alteration affects sleep, but this has not yet been
studiedinadultswithinsomniasymptoms. Weaimedtodeterminetheeffectofasix-monthdiet
interventiononsleepamongoverweightandobese(Bodymassindex,BMI≥25kg/m2)menwith
chronicinsomniasymptoms. Forty-ninemenaged30–65yearswithchronicinsomniasymptoms
wererandomizedintodiet(n=28)orcontrol(n=21)groups. Thedietgroupunderwentasix-month
individualizeddietinterventionwiththreeface-to-facecounselingsessionsandonlinesupervision
1–3timesperweek;300–500kcal/daylessenergyintakeandoptimizednutrientcompositionwere
recommended. Controlswereinstructedtomaintaintheirhabituallifestyle. Sleepparameterswere
determined by piezoelectric bed sensors, a sleep diary, and a Basic Nordic sleep questionnaire.
Comparedtothecontrols,thedietgrouphadshorterobjectivesleeponsetlatencyafterintervention.
Withinthedietgroup,prolongedobjectivetotalsleeptime,improvedobjectivesleepefficiency,lower
depressionscore,lesssubjectivenocturnalawakenings,andnocturiawerefoundafterintervention.
Inconclusion,modestenergyrestrictionandoptimizednutrientcompositionshortensleeponset
latencyinoverweightandobesemenwithinsomniasymptoms.
Keywords: insomniasymptoms;sleep;sleeponset;dietintervention;nutrient;overweight;obesity
1. Introduction
Insomniaisahighlyprevalentsleepdisorderandhasbecomeasignificanthealthissueinmany
countries. TheprevalenceofchronicinsomniasymptomsclassifiedbytheDiagnosticandStatistical
ManualofMentalDisorders,4thEdition(DSM-IV)criteriarangesbetween15.2%and22.1%ofthe
generalpopulationindifferentregionsoftheworld[1–3]. InFinland,nearlyaquarteroftheemployed
people are reported to suffer from insomnia [4]. Insomnia symptoms are risk factors of various
adversehealthconsequences[5]. Forinstance,difficultyinitiatingsleep,thesymptomrepresented
byprolongedsleeponsetlatency(SOL),isindependentlyassociatedwithall-causemortalityamong
Finnishmen[6].
Agrowingbodyofevidencesuggeststhatoverweightandobesityaresignificantriskfactors
forimpairedsleepandinsomnia[7–9]. Population-basedstudyshowedthatobeseadultshadhigher
incidenceofsubjectivesleepdisturbancesthannon-obeseones[9]. Longitudinalstudiessuggested
Nutrients2016,8,751;doi:10.3390/nu8110751 www.mdpi.com/journal/nutrients
Nutrients2016,8,751 2of14
that both obesity and weight gain could predict future development of insomnia symptoms [7,8].
Diet is an important mediator between sleep and overweight/obesity. Growing evidence suggest
that diet alterations can directly influence sleep parameters [10,11]. Furthermore, the associations
betweennutrientsandinsomniasymptomshavebeenreportedbyrecentstudies[12–14]. However,
nopreviousstudyhasinvestigatedwhetherdietinterventionleadstoimprovedsleepparameters
relatedtoinsomniasymptoms,suchassleeponsetlatency. Thereisalsoalackofdataregardingthe
effectsofdiet-inducedweightlossonsleepamongoverweightandobesepopulations,especiallyin
men, among which the combined prevalence of overweight and obesity is higher than women in
Finland[15].
Thus,thepresentstudyaimedtoinvestigatewhethersleepparametersamongoverweightand
obesemenwithchronicinsomniasymptomscanbeimprovedthroughasix-monthdietintervention.
Wehypothesizedthatreducedenergyintakeandoptimizednutrientcompositioncanimproveoneor
multipleobjectivelyandsubjectivelymeasuredsleepparameters.
2. Methods
The present randomized controlled trial forms part of a larger study with different lifestyle
interventionsonmiddle-agedmenwithsleepdisorders(Monitoringandtreatmentofobesity-related
sleepdisorders,ISRCTN77172005). Resultsregardingthecomparisonsbetweenexerciseandcontrol
groups have been reported in an earlier publication [16]. In the present paper, we focus solely on
thecomparisonbetweendietandcontrolgroups. However,togiveanoverallpictureofthestudy,
baselinecharacteristicsandsleepoutcomesatbaselineandsixmonthsacrossthethreegroupsare
summarizedinTablesS1andS2. ThestudywasapprovedbytheEthicsCommitteeoftheCentral
FinlandHealthCareDistrict(7/2011). Informedconsentwasobtainedfromallparticipantspriorto
thebaselinemeasurementsandacopyofthesignedconsentformwasarchived.
2.1. Participants
Participants were 49 Finnish men aged 30–65 years with chronic (three months or longer)
complaints of insomnia symptoms. Ninety-four percent (n = 46) of them had BMI ≥ 25 kg/m2.
Participantswerevoluntarilyrecruitedthroughtheoutpatientclinicsandpublichealthcarecentersin
theCentralFinlandHealthCareDistrict,orthroughadvertisingonthelocalradionewsmediaandthe
Internet. ThesummaryofparticipantflowispresentedinFigure1.
ThemodifiedBasicNordicsleepquestionnaire(BNSQ)[17],thehealthandbehaviorquestionnaire,
andparticipant’smedicalhistorywerecollectedandreviewedbyaphysicianforscreening. Insomnia
symptoms were classified according to the DSM-IV-TR criteria (without the criterion of daytime
consequences) from answers to the modified BNSQ. Individuals were considered to have chronic
insomnia symptoms if one or more of the following symptoms had occurred at least three nights
per week, during the past three months: (1) Difficulty initiating sleep (subjective SOL ≥ 30 min);
(2) Difficulty maintaining sleep (awakening during sleep ≥3 times/night, or difficulty in falling
asleep after nocturnal awakening with total wake after sleep onset ≥30 min); (3) Early morning
awakenings(wakeup≥30minearlierthandesiredinthemorningandunabletofallasleepagain);
(4)Non-restorativesleep[18,19].
Exclusion criteria were: (1) other sleep disorders include moderate or severe apnea
(Apnea-hypopnea index, AHI ≥ 15), restless leg syndrome and periodic leg movement disorder
(periodiclegmovementarousalindex>15),narcolepsy,REMbehaviordisorder,andcircadianrhythm
disorder;(2)Medicalhistoryduringthepastthreeyearsrelatedtodiseasessuchascardiovascular
disease,heartfailure,liverdisease,andcancer;(3)Currentdiagnosisofmajordepression;(4)History
of other major mental illness or substance abuse; (5) History of cognitive impairment and major
neurologicaldisorders;(6)Historyofeatingdisorders;(7)Takingspecialdietatthemoment;(8)Chronic
painconditions;(9)Regularuseofsedatives,hypnotics,andpainkillers;(10)Shiftwork[12].
Nutrients2016,8,751 3of14
Nutrients 2016, 8, 751  3 of 14 

FFigiguurree1 1.. PPaarrttiicciippaanntt ffllooww ooff tthhee sstutuddyy. .
2.2. Measurements 
2.2. Measurements
All measurements were carried out before randomization, and after the six‐month intervention 
Allmeasurementswerecarriedoutbeforerandomization,andafterthesix-monthintervention
period. In addition, nutrient intake and anthropometry were measured at three months. 
period. Inaddition,nutrientintakeandanthropometryweremeasuredatthreemonths.
2.2.1. Descriptive Characteristics 
2.2.1. DescriptiveCharacteristics
Age, education, employment, and smoking habits were elicited at baseline with the health and 
Age,education,employment,andsmokinghabitswereelicitedatbaselinewiththehealthand
behavior questionnaire. Age of onset of insomnia and occurrences of insomnia symptoms were 
behaviorquestionnaire. Ageofonsetofinsomniaandoccurrencesofinsomniasymptomswereelicited
elicited with the baseline modified BNSQ. 
withthebaselinemodifiedBNSQ.
2.2.2. Energy Consumption and Nutrients Intake 
2.2.2. EnergyConsumptionandNutrientsIntake
A three‐day  diet diary (two  weekdays and  one weekend)  collected  the type,  item, and 
esAtimtharteede- dpaoyrtidoine todfi aarlyl f(otwodo awnede kddrianyks ainntdakoen deuwrienegk eenadch) cdoallye.c tAerdchthiveintygp oef, idteiemt ,iannfodrmesattiimona,t ed
porctaiolcnuloaftiaolnl foofo ndutarniedntdsr iinntkakine,t atokteald cuarlionrgiese,a acnhdd paryo.pAorrtcihonivsi nogf eonfedrgieyt‐yinieflodrimnga ntiuotnr,iecnatlsc uinl attoiotanl of
nutcraielonrtisesin (tEa%ke), wtoetrael ccaalrorireieds ,oaunt dbyp rtohpeo Mrtiiocrnos‐Nofuetrniecarg syo-fytiweladrien (gTnhue tSrioecniatsl iInnstuortaanlccea lIonrsietistu(Eti%on) wofe re
carrFiiendlaonudt, bTyurtkhue, MFiinclraon-Nd)u. tricasoftware(TheSocialInsuranceInstitutionofFinland,Turku,Finland).
Nutrients2016,8,751 4of14
2.2.3. AnthropometryandFatMass
Allanthropometricmeasurementswereperformedafterovernightfasting(12h). Heightwas
measured to the nearest 0.5 cm using a fixed wall scale. Weight was determined to the nearest
0.1kgusingacalibratedphysicianweightscale. BMIwascalculatedasweight(kg)perheight2(m2).
Neck,chest,waist,andhipcircumferencesweredeterminedtothenearest0.1cmbyameasuringtape
usingstandardizedprocedures,andtheaveragevalueofthreemeasurementswastakenforanalysis.
Bloodpressureweremeasuredusinganoscillometricmonitorinsittingpositionafterfive-minute
resting, average value of three measurements was retained. Fat mass was determined using dual
energyX-raydensitometry(DXA;Prodigy,GELunar,Madison,WI,USA).
2.2.4. EnergyExpenditures
A seven-day physical activity diary was collected on the same days as sleep measurements.
Thediaryrecordedprimarylivingactivityat30-minintervalsover24h. Energyexpenditureswere
calculated as metabolic equivalent multiplied by minutes per day (MET min/day), according to
the2011CompendiumofPhysicalActivities[20]. Expenditureswerecategorizedintoexerciseand
recreationalactivity(e.g.,walkingadog,berrypicking),livelihoodphysicalactivity(e.g.,personal
care,housework,commuting,occupationalactivities),aswellassedentarybehaviors(METs≤1.5
whileinasittingorrecliningposture)andsleep[21].
2.2.5. ObjectiveSleepMeasurement
Home-based objective sleep data were collected by an unobtrusive online sleep monitoring
system (Beddit pro; Beddit Ltd., Espoo, Finland). The system included a piezoelectric bed sensor.
Ballistocardiographicsignalsweresampledbythepiezoelectricsensorat140Hzandsimultaneously
uploadedtoawebserverthroughtheInternet,wheresleep/wakestatuswasclassifiedin30-sepochs
based on heart rate variability, respiration rate variability, and binary actigram [22]. An ambient
brightnesssensor,includedinthesystem,wasplacedinthebedroomfordetermininglights-outtime.
For participants who had a bed partner, sensor attachment was considered to avoid overlapping
measurements. Participants were instructed to mention conditions that might have affected the
measurements,suchaschildrenandpetsinthebedroom,inthesleepdiary. Measurementwasset
automatically to start each evening at 18:00, and end at noon the next day. Total sleep time (TST),
SOL(determinedasthedurationfrombeingpresentinbedwithlightsouttothefirstfiveminutesof
consecutivesleep)[23],wakefulnessaftersleeponset(WASO),andsleepefficiency(SE)wereobtained
for each night. Sleep was measured for seven nights, including two weekends. Measurements
weretakenwithin14daysbothbeforeandafterthesix-monthstudyperiod. Foranalyses,average
valuesacrossthenightswereused; atleastfivenights’validdataatbothbaselineandsixmonths
were needed. Validation of the sleep/wake in 30-s epochs was carried out against two-night
polysomnographymeasurement(31subjectswithinsomniacomplaints,age(±SD)=51.8±8.4years,
BMI=30.9±4.8kg/m2). Correlations in sleep outcomes were obtained as follow: TST (Pearson’s
r=0.85, p < 0.001), SOL (Pearson’s r=0.81, p < 0.001), WASO (Kendall’s tau-b = 0.74, p<0.001),
SE(Kendall’stau-b=0.68,p<0.001)[16].
2.2.6. SleepDiaryandModifiedBNSQ
The seven-night sleep diary was collected on same nights with objective sleep measurement.
Itemsincludedtimeofgoingtobed,estimatedtimeoffallingasleep,numberofnocturnalawakenings,
finalwaking-uptime,morning-ratedsubjectivesleepquality,fatigueuponawakening,napduration,
andotherissuesrelatedwithsleep. Theaveragevaluesfortherecordednightswereusedforanalyses.
Epworthsleepinessscale(ESS)score[24],Rimon’sbriefdepressionscalescore[25],insomniasymptom
frequency,andothersubjectivesleepassessmentresultswereelicitedbythemodifiedBNSQ.
Nutrients2016,8,751 5of14
2.3. Randomization
After the baseline measurements, participants were randomized and allocated into the diet
interventionorcontrolgroup,byanexternalstatistician. Randomizationwasstratifiedbyageand
BMI(≤or>medians)withablocksizeof5,usingSASv. 9.2,(SASInstitute,Cary,NC,USA).
2.4. InteractiveDietIntervention
A six-month individualized diet intervention program was made according to the three-day
dietdiaryresultsandBMIatbaseline. Individualizedprogramswereintroducedtoeachparticipant
face-to-face by study nutritionists on the first day of intervention. Diet suggestions were made
accordingtotheFinnishNutritionRecommendations[26]. Suggestedproportionsofenergy-yielding
nutrients were: 40%–45% of carbohydrate in total daily energy intake (E%) with <5 E% sucrose;
35–40E%totalfatwith≤10E%saturatedfattyacids(SFA),15–20E%monounsaturatedfattyacids
(MUFA),and5–10E%polyunsaturatedfattyacids(PUFA);and20E%protein[26]. Inaddition,greater
consumptionofdietaryfiber,vitaminA,vitaminD,vitaminE,Bvitamins,vitaminC,magnesium,
andpotassiumwasrecommendedthroughselectedfoodoptions(cereals,vegetables,fruits,berries,
nuts,legumes,mushrooms,etc.). Participantswithoverweightandobesity(n=27)wereadvisedto
graduallyreducetheirdailyenergyintakeby300–500kcalduringthefirstthreemonths,withatarget
ofreducing bodyweightby3kg. Afterthisperiod, calorieintakewassuggestedto remainatthe
reducedlevel. Twointermediateface-to-facecounselingsessionswereheldinthefirstandthefourth
monthoftheintervention. Eachintermediatesessioninvolvedindividualizeddietcounselingwitha
nutritionist,andacookingcourseinwhichexamplesofmealsthatfulfilledthenutritionalcriteriaof
thisstudywereintroduced.
Duringtheintervention,anonlinedietandnutritioncounselingservice(MealTracker,Wellness
Foundry Holding Ltd., Helsinki, Finland) was utilized for supervising individuals’ dietary intake
andprovidingdietsuggestions. Participantswereinstructedtophotographalldailydietaryintakes
(includingdrinks)usingasmartphoneoradigitalcamera,anduploadallphotostotheserver1–3days
perweekduringtheintervention. Thephotoswereuploadedviaamobileapplication,orthrough
the service’s website. According tothe uploadedphotos, a nutritionistassessed eachindividual’s
dailycalorieintakeandconsumptionsofnutrients. Individualizedfeedbackincludingdietaryintake
facts and instructions for diet adjustment in the upcoming days was thus formulated and sent to
participantsviamobiletextmessageande-maileachdaywithuploadedinformation. Dietphotos
weresavedineachparticipant’saccountintheserver,whichwasonlyaccessibletotheparticipant
andthenutritionist. Atrainingsessionfortakinganduploadingdietphotoswasheldpriortothe
intervention. Allparticipantsinthedietgroupwereabletousetheservicecorrectly.
2.5. ControlGroup
Controlswereinstructedtokeeptheirhabitual,pre-recruitmentlifestyleforsixmonths.Theywere
givenanopportunitytoparticipateinthedietplusexerciseinterventionprogramforthreemonths
afterthestudyperiod.
2.6. StatisticalAnalysis
TheestimatedchangeoftheobjectiveSOLwasbasedonpublisheddata[16,27]. Statisticalpower
wasover80%todetecta30%loweredSOLinthedietgroupfrombaseline,andnochangeofSOLin
thecontrolgroup,withtheunbalancedallocationof28and21participantsineachrandomizedgroup.
Analyseswerecarriedoutfollowingtheintention-to-treatprinciple. Forparticipantswithmissing
orincompletevaluesatfollow-ups,thelastobservedvalueswerecarriedforward. Allanalyseswere
performedusingIBMSPSSstatisticsversion20(SPSS,Inc.,Chicago,IL,USA).Alltestsweretwo-tailed;
apvaluelessthan0.05wassetassignificant. TheShapiro–WilkWtestandLevene’stestwereused
toexaminethenormalityandhomogeneity,respectively. Skeweddataweretransformedbynatural
Nutrients2016,8,751 6of14
logarithm. Baseline differences between groups were evaluated by one-way analysis of variance
(ANOVA),orPearson’sχ2test. Time-by-groupdifferenceswereevaluatedbyanalysisofcovariance
(ANCOVA),controllingforthebaselinevalues. Within-groupdifferenceswereevaluatedbyrepeated
measures ANOVA, followed with Bonferroni corrections for multiple comparisons. In addition,
Pearson’scorrelationcoefficientswerecalculatedbetweenchangesfrombaselinetosixmonthsfor
selectedvariables.
3. Results
BaselinedescriptivecharacteristicsbygrouparegiveninTable1. Retentionratesbetweendiet
andcontrolgroupswerecomparable(Diet=26/28,Control=19/21,p=0.579,Fisher’sexacttest).
Table1.Descriptivecharacteristicsatbaseline.
Diet(n=28) Control(n=21)
p#
Mean(95%CI) Mean(95%CI)
Age(year) 51.0(47.3to54.8) 52.6(48.0to57.2) 0.592
Agewheninsomniacomplaintstarted(year) 37.4(33.1to41.6) 39.8(33.7to46.0) 0.482
Height(cm) 178.9(177.0to180.8) 178.3(175.6to180.9) 0.696
Weight(kg) 93.8(89.2to98.4) 93.1(85.2to100.9) 0.860
BMI(kg/m2) 29.4(27.9to30.8) 29.2(27.2to31.2) 0.879
Systolicbloodpressure(mmHg) 142.8(139.0to146.6) 140.7(135.2to146.3) 0.513
Diastolicbloodpressure(mmHg) 88.8(84.9to92.6) 91.4(86.7to96.1) 0.363
Occurrences Percentage Percentage
Difficultyinitiatingsleep 42.9 42.9 1.000
Difficultymaintainingsleep 57.1 76.2 0.166
Earlymorningawakenings 32.1 23.8 0.523
Non-restorativesleep 39.3 42.9 0.801
Smokingpresently 14.3 19.0 0.655
Atleasttertiarydegreeeducation 82.1 95.2 0.166
Employed 82.1 71.4 0.374
#One-wayANOVAorPearson’sχ2test.
3.1. CompliancewithDietInterventions
Onaverage,participantsinthedietgroupwhoattendedthesix-monthfollow-upmeasurements
uploaded1.9 ± 1.1(SD)daysperweekduringintervention. Alloftheseparticipantsattendedall
threecounselingsessions. Twoparticipantsdroppedoutduringthefirstmonthofthestudy,bothdue
totheunwillingnesstochangediet. Therewerenodietphotosuploadedfromtheparticipantswho
droppedout.
3.2. EnergyConsumptionandNutrientIntake
Within the diet group, total energy intake was reduced at six months compared to baseline
(p = 0.006, Figure 2); however, changes in other nutrients were not detected. Total energy intake
was reduced at three months in both groups (p = 0.001 and 0.012, respectively). Proportions of
energy-yieldingnutrientsintotalcaloriesdidnotshowsignificantchangeineithergroup. Compared
tothecontrols,thedietgrouphadgreaterintakesofpotassium(2158vs. 1806mg/1000kcal,p=0.029,
ANCOVAcontrollingforbaseline)andmagnesium(219vs. 193mg/1000kcal,p=0.036,ANCOVA
controllingforbaseline)atthreemonths(notshowninfigure).
Nutrients2016,8,751 7of14
Nutrients 2016, 8, 751  7 of 14 
Total calorie intake per day (kcal)
2500
2400
2300
2200
2100 *
*
*
2000
1900
1800
1700
1600
1500
Diet Control
Baseline 3 months 6 months
Data are shown as mean (95% CI).
* p < 0.05, compared to the baseline values,repeated-measures ANOVA with Bonferroni
post hoc comparisons.

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3.3. Anthropometry, Fat Mass, and Energy Expenditures 
3.3. Anthropometry,FatMass,andEnergyExpenditures
Body weight, total fat mass, and waist circumference decreased significantly in the diet group 
Bodyweight,totalfatmass,andwaistcircumferencedecreasedsignificantlyinthedietgroup
compared to the control group (p = 0.043 to 0.009, Table 2). No significant changes in physical 
compareadctitvoittyh, esecdoennttraorly gtriomuep, o(pr =tot0a.l0 4e3netrogy0 .0e0xp9,enTdaibtulere2 )w.eNreo fsoiugnndifi icna netitchhera nggroeuspi ndpuhriynsgi ctahle activity,
sedentarinytetrimveen,tioonr.t otalenergyexpenditurewerefoundineithergroupduringtheintervention.
Table 2. Anthropometry, fat mass, and energy expenditures at baseline and follow‐ups. 
Table2.Anthropometry,fatmass,andenergyexpendituresatbaselineandfollow-ups.
Diet  Control 

Baseline  3 MoDnitehts  6 Months Baseline 3 MonthCs ontrol6 Months
Anthropometry  
Baseline 3Months 6Months Baseline 3Months 6Months
92.7 (88.3 to  92.7 (88.1 to  93.1 (85.2 to  93.5 (85.5 to  94.4 (86.3 to 
Weight (kg)  93.8 (89.2 to 98.4) 
Anthropometry 97.0) #  97.4) #  100.9)  101.5) #  102.5) *,# 
Neck circumference  41.9 (40.9 to  42.2 (41.3 to  41.9 (40.6 to  42.0 (40.5 to  42.6 (41.2 to 
42.0 (41.903 t.o8 43.0)  92.7 92.7 93.1 93.5 94.4
Weight(k(gcm))  (89.2to98.4) (884.33.t0o) 97.0)# (8483.1.2t)o  97.4)# 4(38.53.)2 to100.9) 43.(48)5 .5to101.5)#44.0) (*8 6.3to102.5)*,#
Chest circumference  109.4 (4120.60.8 to  109.2 (14016.9.5 to  109.7 (10462.9.2 to  107.7 (102.461 t.o9  108.0 (102.9 42.0109.5 (104.5 to 42.6
Neckcircumfere(cnmce) (cm) (411.102t.o0)4 3.0) (4011.91.t9o) 43.0) (14112..35)t o43.2) 11(24.09.)6 to43.3) to 113(.410) .5to43.4)114.5) * (41.2to44.0)*
Waist circumference  106.6 1(10092.4.9 to  106.1 (110092..27 to  105.9 (10120.94. 7to  105.0 (99.190 t7o. 7 105.4 (99.9 t1o0 8.0106.7 (101.3 to 109.5
Chestcircumfere(cnmce) (cm) (1061.180t.o2)1 12.0) (10610.59.t4o) 111.9) (110096..49) t#o 112.5) 1(1100.21.)6 to112.9) 110(.180) 2 .9to113.111)2.2) *(,1# 04.5to114.5)*
WaistcHiricpu cmirfceurmenfceere(nccme )(cm)  1(0140.251. 091(710t.0o611).6.1 91 t0o. 2) 1(0130.121 0.(71610.0t1o60).. 111 0t9o. 4) 10(31.510 02(6.14.0170t0)o. 541. 9t0o9 .4)#102.17(0 9(699.78.9).16 t0 ot5o.1 010.1)103.150 (79.(399).96 . 9t1ot0 o5.141100.48.)01 0(81.010()1. 00 t1o.3 1t0o61.712.2)*,#
Fat mass  104.5 103.1 103.5 102.7 103.5 104.0
Hipcircumference(cm)
(101.9to107.1) (100.1to106.1) 26(.180 (02.34.5to to1 06.7) 28.0( (9283..66 ttoo 106.7) (99.6to1072.83.)9 (24.0( 1to0 0.0to108.1)
Total fat mass (kg)  27.5 (24.2 to 30.7)  n/a  n/a 
Fatmass 30.2) #  32.5)  33.8) *,# 
17.2 (15.1 to  17.7 (14.5 to  18.2 (14.9 to 
TotEanlTefarrugtynm kea xfsapste (mnkdgai)stsu (rkegs )  17.6(2 (41.52.26t7 ot.o53 109.7.6))  n/na/ a (2139.5.32t)o 6.380.2)# 2(02.83). 62t8o.032.5) n/a  n/a 21.5) *( 24.0t2o83.93.8)*,#
17.6 17.2 17.7 18.2
TrunTkotfaalt emxpaesnsd(iktugr)e (MET  2346.1 (2254.9 to  n/a 2398.8 (2299.7  2341.1 (2224.0  n/a2322.6 (2210.0 
(15.6to19.6) n/a  (15.1to19.3) (14.5to20.8) n/a  (14.9to21.5)*
min/day)  2437.3)  to 2498.0)  to 2458.1)  to 2435.3) 
EnergyexpendituErxeesrcise and 
226.7 (150.8 to  292.5 (194.5 to  249.5 (145.2 to  254.3 (151.9 to 
Totalexpenadcritetiucvrrieteya( tM(iMonEEaTTl  pmmhiiynns//idcdaaayl y) ) (22543.20932t4.6o6). 21437.3) n/na/ a (22399902..743)9t o8.28498.0) (325232.48.2)0 3t4o1.21458.1) n/a  n/a 356.7()2 2102.032to2.26435.3)
ExercaicsteivaintyadcH(trMievociuErteysTea (hmtMiooilEnndT/a p ldmhpayihynsy)/idcsaaicly a)l  8(4105.1090. 82(0626t7o6.55.).734 0 t2o. 6) n/na/ a 845(.11490 (0460.852.999t).o29 . 5t3o9 0.4)803.09( 71(464.3551.)22. 54t o9to.53 53.8) n/a  n/a751.69 5(45.468). (61 5to1 .925to4.3356.7)
Householdphysicalactivity 840.9 845.4 803.0 751.6
n/a n/a
(METmin/day) (675.4to1006.5) (689.9to1000.9) (631.5to974.5) (548.6to954.6)
  846.7 801.7 824.6 845.0
Sedentarybehaviors(METmin/day) n/a n/a
(739.0to954.4) (706.1to897.3) (737.1to912.1) (758.3to931.7)
Dataareshownasmean(95%CI);#p<0.05,comparedtotheothergroup,analysesofcovariancecontrolling
forbaselinevalues;*p<0.05,comparedtothebaselinevalues,repeatedmeasuresANOVAwithBonferroni
posthoccomparisons.
Nutrients 2016, 8, 751  8 of 14 
Sedentary behaviors  846.7 (739.0 to  801.7 (706.1 to  824.6 (737.1 to  845.0 (758.3 to 
n/a  n/a 
(MET min/day)  954.4)  897.3)  912.1)  931.7) 
Data are shown as mean (95% CI); # p < 0.05, compared to the other group, analyses of covariance 
Nutrients2016,8,751 8of14
controlling for baseline values; * p < 0.05, compared to the baseline values, repeated measures 
ANOVA with Bonferroni post hoc comparisons. 
3.4. ObjectiveSleepParameters
3.4. Objective Sleep Parameters 
At baseline, the valid objective sleep data for analyzing were on average 6.4 ± 1.1 and
At baseline, the valid objective sleep data for analyzing were on average 6.4 ± 1.1 and 6.8 ± 0.6 
6.8±0.6nightsindietandcontrolgroups,respectively. Atsixmonths,thecorrespondingnumbers
nights in diet and control groups, respectively. At six months, the corresponding numbers were 6.4 ± 
were6.4±0.9and6.6±0.7. Therewasnobetween-groupdifferenceinthenumberofnightsanalyzed
0.9 and 6.6 ± 0.7. There was no between‐group difference in the number of nights analyzed at 
at baseline or six months (p = 0.110 and 0.613, respectively, one-way ANOVA). Nights marked by
baseline or six months (p = 0.110 and 0.613, respectively, one‐way ANOVA). Nights marked by 
parptiacritpicainpatsntass abse bineigngs usbujbejcetctt otos isgignnifiifcicaanntt ddiissttuurrbbaannccee iinn tthhee mmeeaasusurermemenetn ptrporcoecsse s(ssu(cshu cahs aas paetp et
sleespleienpgining tinh ethbee dbe)dw) ewreereex ecxluclduedde.dR. Reseusultlstso offt htheeo obbjejeccttiivvee sslleeeepp mmeeaassuurreemmeennttss aarree ggiivveenn inin FFigiguurer e3.
Com3. pCaormedpatroedth teo cthoen tcroonltrgorlo gurpo,utph, ethdei edtiegt rgoruopups hshoowweedd sshhoorrtteerr SSOOLL ((pp << 0.00.0010)1 a)ftaefrt einrtienrtveernvteionnt.i on.
WitWhiinthtinh ethdei edtiegtr oguropu,pp, rporloolnognegdedT TSSTT( p(p == 00..000044)),, ccuurrttaaiilleedd SSOOLL (p(p << 0.00.0010)1, )a,nadn dincinrecarseeads esdleesple ep
effiecfifeinciceyncwy ewreerfeo ufonudnd(p (p= =0 .00.0040)4)t hthrorouugghh iinntteerrvveennttiioonn.. IInn ththee ddieite tggroruopu,p c,hcahnagneg oef oofbojebcjteivctei vSeOSLO  L
throthurgohugihn tienrtverevnetniotinond iddidn noottc ocorrrreelalattee wwiitthh cchhaannggeess iinn bbooddyy wweiegihgth toro rfafta mt masas s(sbo(btho tph >p 0>.050,. 05,
PeaPresaorns’osnr’)s. r). 
Total sleep time (minutes) Sleep onset latency (minutes) †
460 40
#
440 35
*
420 30
400 25
380 20
*, #
360 15
340 10
320 5
300 0
Diet Control Diet Control
Wake after sleep onset (minutes) † Sleep efficiency (%) †
60 100
55 95
*
50 90
45 85
40 80
35 75
30 70
25 65
20 60
Diet Control Diet Control
Data are shown as mean (95% CI). Baseline 6 months
† Analyses on Natural Log transformed data.
* p < 0.05, compared to the baseline values,repeated-measures ANOVA.
# p < 0.05, compared to the other group, analysis of covariance controlling for baseline value.  
Figure 3. Sleep outcomes by piezoelectric system at baseline and six months. 
Figure3.Sleepoutcomesbypiezoelectricsystematbaselineandsixmonths.
3.5. Subjective Sleep Assessments 
3.5. SubjectiveSleepAssessments
No time‐by‐group difference was detected among subjective sleep parameters (Table 3). Within 
Notime-by-groupdifferencewasdetectedamongsubjectivesleepparameters(Table3).Withinthe
the diet group, nocturnal awakenings (p = 0.035), number of nocturia (p = 0.001), and Rimon’s 
dietgroup,nocturnalawakenings(p=0.035),numberofnocturia(p=0.001),andRimon’sdepression
depression score (p = 0.029) were reduced compared to the baseline values. 
score(p =0.029)werereducedcomparedtothebaselinevalues.
Nutrients2016,8,751 9of14
Table3.Sleepoutcomesbysleepdiaryandsleepquestionnaireatbaselineandsixmonths.
Diet Control TimebyGroup
Baseline 6Months p Baseline 6Months p p#
Sleepdiary
Sleeponsetlatency(min)† 21.0(13.5to31.0) 20.0(13.3to23.8) 0.122 21.5(17.3to41.8) 25.0(15.0to42.5) 0.463 0.255
Nocturnalawakenings(numbers/night) 2.3(1.8to2.9) 1.8(1.3to2.4) 0.035 2.6(1.8to3.4) 2.3(1.8to2.8) 0.293 0.305
Nocturia(times/night) 0.8(0.6to1.1) 0.5(0.3to0.6) 0.001 0.7(0.4to0.9) 0.5(0.3to0.8) 0.080 0.075
Morning-ratedsleepquality(1–4)a 2.4(2.1to2.7) 2.7(2.4to2.9) 0.094 2.4(2.2to2.5) 2.4(2.2to2.6) 0.785 0.153
Fatigueuponawakening(1–4)b 2.2(2.0to2.4) 2.0(1.7to2.2) 0.062 1.9(1.6to2.1) 2.0(1.8to2.2) 0.300 0.292
Nap(min/day)* 17.1(11.2to23.1) 14.0(8.1to19.9) 0.388 12.5(4.4to20.6) 11.9(2.2to21.6) 0.885 0.957
Sleepquestionnaire
Difficultyinitiatingsleep(1–5)c 2.5(2.0to3.0) 2.3(1.9to2.7) 0.227 2.8(2.2to3.3) 2.7(2.1to3.2) 0.540 0.376
Earlymorningawakenings(1–5)c 3.0(2.5to3.5) 2.8(2.2to3.3) 0.246 3.0(2.5to3.5) 3.1(2.5to3.7) 0.452 0.182
Sleeplessthan5hinlastmonth(1–6)d 2.9(2.4to3.3) 2.6(2.1to3.1) 0.355 3.0(2.3to3.6) 2.8(2.2to3.3) 0.384 0.718
Habitualsleepduration(h) 6.6(6.1to7.1) 6.7(6.2to7.2) 0.706 6.7(6.2to7.2) 6.6(6.1to7.1) 0.545 0.658
Desiredsleepduration(h) 7.9(7.5to8.4) 7.8(7.3to8.3) 0.398 8.1(7.6to8.5) 7.9(7.5to8.3) 0.117 0.776
Epworthsleepinessscalescore 6.6(5.2to8.0) 6.3(4.9to7.7) 0.612 8.3(6.2to10.5) 7.4(5.2to9.7) 0.056 0.679
Rimon’sdepressionscore† 5.0(4.0to7.0) 4.0(1.3to6.0) 0.029 4.0(3.0to7.5) 3.0(2.5to5.5) 0.187 0.358
Dataareshownasmean(95%CI)unlessspecifiedotherwise;†ComparisonsunderNaturalLogtransformeddata,valuesareshownasthemediansand25ththrough75thpercentiles;
#Analysesofcovariancecontrollingforbaselinevalues;*Diet(n=19),Control(n=12);a1=Verypoor;2=Quitepoor;3=Good;4=Verygood;b1=Notfatiguedatall;2=Alittle
fatigued;3=Quitefatigued;4=Veryfatigued;c1=Never/lessthanoncepermonth;2=Lessthanonceperweek;3=1–2daysperweek;4=3–5daysperweek;5=dailyoralmost
daily;d1=0night;2=1–5nights;3=6–10nights;4=11–15nights;5=16–20nights;6=morethan20nights.