Mon ei o, So ia; Pujol-Busque s, Geo gina; Smi h, James; La mu h, Ka e
A icle — Published Ve sion
The impac o a low-ca bohyd a e nu i ion educa ion p og am on ood
p e e ences: The co espondence be ween sel - epo consump ion
and supe ma ke pu chases
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(2025) : The impac o a low-ca bohyd a e nu i ion educa ion p og am on ood p e e ences: The
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OPEN ACCESS
Ci a ion: Mon ei o S, Pujol-Busque s G, Smi h J,
La mu h K (2025) The impac o a low-
ca bohyd a e nu i ion educa ion p og am on
ood p e e ences: The co espondence be ween
sel - epo consump ion and supe ma ke
pu chases. PLoS ONE 20(4): e0319503.
h ps://doi.o g/10.1371/jou nal.pone.0319503
Edi o : Meh an Rahimlou, Zanjan Uni e si y o
Medical Sciences, I an, Islamic Republic O
Recei ed: May 23, 2024
Accep ed: Feb ua y 3, 2025
Published: Ap il 8, 2025
Copy igh : © 2025 Mon ei o e al. This is an
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which pe mi s un es ic ed use, dis ibu ion,
and ep oduc ion in any medium, p o ided he
o iginal au ho and sou ce a e c edi ed.
Da a a ailabili y s a emen : All da a a e wi hin
he pape and i s Suppo ing In o ma ion
iles, as well as a he ollowing Ha a d
Da a e se link: Mon ei o, So ia; Pujol-
Busque s, Geo gina; Smi h, James; La mu h,
Ka e, 2025, "Replica ion Da a o : The impac
o a low-ca bohyd a e nu i ion educa ion
p og am on ood p e e ences: The co e-
spondence be ween sel - epo consump ion
RESEARCH ARTICLE
The impac o a low-ca bohyd a e nu i ion
educa ion p og am on ood p e e ences:
The co espondence be ween sel - epo
consump ion and supe ma ke pu chases
So ia Mon ei o 1*, Geo gina Pujol-Busque s 2,3, James Smi h4,5,6, Ka e La mu h 4,5,6
1 Global Heal h Resea ch G oup, Kiel Ins i u e o he Wo ld Economy, Kiel, Schleswig-Hols ein,
Ge many, 2 Facul y o Heal h Sciences, Uni e si a Obe a de Ca alunya (Open Uni e si y o Ca alonia,
UOC), Ba celona, Ca alonia, Spain, 3 MRC/Wi s Ru al Public Heal h and Heal h T ansi ions Resea ch
Uni (Agincou ), School o Public Heal h, Facul y o Heal h Sciences, Uni e si y o he Wi wa e s and,
Johannesbu g, Gau eng, Sou h A ica, 4 Heal h h ough Physical Ac i i y Li es yle and Spo Resea ch
Cen e, Spo s Science Ins i u e o Sou h A ica, Uni e si y o Cape Town, Cape Town, Wes e n Cape,
Sou h A ica, 5 In e na ional Fede a ion o Spo s Medicine (FIMS) Collabo a i e Cen e o Spo s
Medicine, HPALS, Uni e si y o Cape Town, Cape Town, Wes e n Cape, Sou h A ica, 6 Di ision o
Physiological Sciences, Depa men o Human Biology, Uni e si y o Cape Town, Cape Town, Wes e n
Cape, Sou h A ica
* so ia.mon ei [email p o ec ed]
Abs ac
The e is easonable conce n ha sel - epo ed nu i ion assessmen s do no e lec ac ual
ood choices. Ye , a co espondence be ween bo h is impe a i e o e alua e any in e -
en ion on ood p e e ences. This pape makes such a compa ison. I p o ides e idence
om a low-ca bohyd a e nu i ion educa ion p og am, which is assessed wi h bo h su eys
and an incen i ized beha io al measu e o ood choice. The main esul is ha he e is
a la ge co espondence be ween su ey and beha io al measu es o ou sample o 95
women om wo his o ically unde p i ileged communi ies in he Wes e n Cape, Sou h
A ica. Compa ed o he con ol, he ea men g oup epo ed a 35% lowe in ake om
he high-ca bohyd a e/ ul a-p ocessed ood Red Lis and 60% highe in ake om he
low-ca bohyd a e whole oods G een Lis . The ea men g oup was also 40% less likely
o buy any hing om he Red Lis wi h a supe ma ke ouche . In e ms o he G een Lis ,
he ea men g oup was signi ican ly mo e likely o buy eggs, o gan mea , adi ional a s,
a ocado and ish bu he e was no di e ence in ed mea and chicken, non-s a chy ege-
ables and ull c eam dai y. Low-cos incen i ized measu es o e ealed p e e ences can
be designed o alida e subjec i e habi s, inc easing con idence in he quali y o e idence
om nu i ion in e en ion s udies.
In oduc ion
The bu den o non-communicable diseases (NCDs) such as ype 2 diabe es is d i en o a
g ea ex en by wha people ea and d ink. Hence, in luencing die a y beha io o disease
p e en ion and managemen has become a key challenge o policymake s [1]. In esponse,
PLOS ONE | h ps://doi.o g/10.1371/jou nal.pone.0319503 Ap il 8, 2025 2 / 16
PLOS ONE The impac o a low-ca bohyd a e nu i ion educa ion p og am on ood p e e ences
beha io al economis s ha e explo ed “How do we pe suade people o ea be e and lose
weigh ?” [2] and “How do we make he heal hie choice he easie choice?” [3]. The e is a gu-
ably a need o e idence-based, sus ainable die a y in e en ions ha conside how people
alloca e hei sca ce esou ces (money, ime and a en ion) o imp o e heal h [4]. Ye , he e
is cu en ly s ill no consensus on how o measu e die a y change accu a ely (in a eal-wo ld
se ing) adding o he challenge o imp o ing people’s die a y p e e ences. While his is yp-
ically pe o med wi h sel - epo ed su eys, he e is eason o belie e ha wha people say is
no always wha hey do – as is, well known ega ding physical ac i i y [5], bu deba ed wi h
espec o die a y in ake [6,7]. Ou s udy con ibu es o an eme ging li e a u e on he beha -
io al economics o ood choice [8–14].
Epidemiological obse a ional s udies, such as he much-ci ed Nu ses’ Heal h S udy,
ha e signi ican ly in luenced public heal h policy and p ac ice globally [15–18]. Such s udies
o die a y isk ac o s use assessmen s ha equi e subjec i e esponses (namely he Food
F equency Ques ionnai e (FFQ), 24-hou ood ecalls and ood dia ies) o make conclusions
abou he op imal die o popula ions. I is unde s ood ha subjec i e measu es o ood
p e e ences may su e om hypo he ical bias and a lack o incen i e o accu acy [13,19], and
in FFQs, he e may be noise due o people’s ina en ion o wha hey ypically ea , inabili y o
ecall ully, and social desi abili y bias [6,7].
We collabo a ed wi h he Ea Be e Sou h A ica (EBSA) p og am, a communi y-based
non-p o i o ganiza ion which uns nu i ion educa ion p og ams in Ocean View and A lan-
is; wo unde - esou ced communi ies in he Wes e n Cape. Pas p og ams we e six weeks
long and in ol ed weekly wo-hou educa ional sessions a a cen al communi y hall wi h a
g oup limi ed o abou 30 women. These sessions aim o each pa icipan s abou nu i ion,
NCDs, shopping on a budge , cooking and how o access heal hie oods. The p og am uses
he Noakes Founda ion’s a ic ligh s lis s o oods which a e a ailable o he public and ee
o download (al e na i ely, see S1 Fig). Pee suppo ia he ins an messaging g oup is cen al
o he p og am, and engagemen in he g oup cha con inues a e he six-week cou se ends.
In ou p e ious quali a i e s udy, he nu i ion educa ion p og am was e alua ed using a di -
e en me hodology, namely ocus g oup discussions on women’s pe cep ions o he p og am,
li es yle choices and shopping habi s [20].
Va ious die s a e ou ed bo h in he nu i ion li e a u e and in public opinion, bu he
quali y o e idence o hem a ies [21]. We posi ha he beha io al measu emen o ood
choice is a complemen a y ool ha could inc ease me hodological c edibili y o nu i ion
in e en ion s udies. The e is, howe e , no gold s anda d o di ec ly assessing he alidi y
o he FFQ [22]. Mo eo e , an e idence base ounded on sel - epo su ey ins umen s is
a guably p oblema ic [6]. The e o e, we pose he ques ion, do e ealed ood p e e ences co -
obo a e sel - epo esponses in he FFQ? This is an open empi ical ques ion since in ano he
heal h- ela ed beha io , physical ac i i y, no co ela ion be ween sel - epo esponses and
beha io was ound [5]. The p esen c oss-sec ional s udy compa es he ood choices o
44 women who had aken pa in a low-ca bohyd a e high- a nu i ion educa ion p og am o
51 simila women who had no ye aken pa bu quali ied o he p og am, using wo com-
plimen a y die assessmen ools: pu chases made wi h a supe ma ke ouche and an FFQ.
Ma e ials and me hods
S udy design
We conduc ed a non- andomized c oss-sec ional quan i a i e s udy wi h wo g oups: a
ea men g oup o women who had al eady comple ed he EBSA p og am and a con ol
g oup consis ing o women who a e eligible o u u e p og ams in he same communi ies.
and supe ma ke pu chases", h ps://doi.
o g/10.7910/DVN/G36VF6, Ha a d Da a e se,
V1, UNF:6:MZOKGXndixByE85oFJUu g==
[ ileUNF]
Funding: This esea ch was unded by SM’s
esea ch budge du ing a Resea ch Fellowship
a The Max Planck Ins i u e o Resea ch
on Collec i e Goods, Bonn. SM’s con ibu-
ion was also suppo ed by he Deu sche
Fo schungsgemeinscha (DFG, Ge man
Resea ch Founda ion) unde Ge many’s
Excellence S a egy – EXC 2167-390884018.
KL’s sala y was unded by he Na ional
Resea ch Founda ion o Sou h A ica. GPG
is a ecipien o he Tim and Ma ilyn Noakes
pos doc o al ellowship. The unde s had
no ole in s udy design, da a collec ion and
analysis, decision o publish, o p epa a ion o
he manusc ip .
Compe ing in e es s: The au ho s ha e
decla ed ha no compe ing in e es s exis . GPG
is a ecipien o he Tim and Ma ilyn Noakes
pos doc o al ellowship. The unde s had no
ole in he design o he s udy; in he collec ion,
analyses, o in e p e a ion o da a; in he
w i ing o he manusc ip ; o in he decision o
publish he esul s.
PLOS ONE | h ps://doi.o g/10.1371/jou nal.pone.0319503 Ap il 8, 2025 3 / 16
PLOS ONE The impac o a low-ca bohyd a e nu i ion educa ion p og am on ood p e e ences
The design allowed us o iden i y he impac o pa icipa ing in he p og am by con olling o
obse able indi idual cha ac e is ics. Ou con ol g oup p o ides a con incing coun e ac ual
o he ea men g oup, since he women sha e many simila obse able cha ac e is ics. This
means ha , i ound, a signi ican di e ence in e ealed ood p e e ences be ween he wo
g oups can be a ibu ed wi h a high deg ee o con idence o he p og am. Fig 1 p o ides a
low diag am o he s udy.
S udy p ocedu es
Pa icipa ion in he s udy ook app oxima ely 90 minu es. Each pa icipan comple ed: (a)
in o med consen ; (b) a ques ionnai e on socioeconomic challenges, medical condi ions, ood
insecu i y and shopping habi s; (c) a ask, in which hey pu chased ood and (non-alcoholic)
d ink i ems in a local supe ma ke wi h a e ail ouche and pho og aphed hei g oce ies and
eceip ; (d) a Food F equency Ques ionnai e; and (e) a eedback ques ionnai e abou hei
Fig 1. Flow diag am.
h ps://doi.o g/10.1371/jou nal.pone.0319503.g001
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PLOS ONE The impac o a low-ca bohyd a e nu i ion educa ion p og am on ood p e e ences
expe ience. In e iew 1 comp ised (a) and (b), while In e iew 2 la e in he week comp ised
(d) and (e).
E hical compliance
The s udy was conduc ed in acco dance wi h he Decla a ion o Helsinki, and app o ed by he
Human Resea ch E hics Commi ee a he Uni e si y o Cape Town (HREC REF 295/2019) on
5 Augus 2019, as well as by he Uni e si y o Cologne Facul y o Managemen Economics and
Social Sciences E hics Commi ee on 25 No embe 2019 (Re e ence: 19024SM) and he p o o-
col amendmen making he en i e s udy emo e o be complian wi h Co id-19 p o ocols was
app o ed 5 June 2020.
In o med consen
In o med consen was ob ained om all subjec s in ol ed in he s udy. Pa icipan s ecei ed
s udy in o ma ion depending on whe he hey we e in he ea men o con ol g oup
and in og aphics explaining he s eps in ol ed in he s udy ia Wha sApp message. To ge
in o med consen ia elephone in e iew, he esea ch assis an explained he s udy, sen he
pa icipan he Qual ics su ey ia Wha sApp, ended he call o a couple o minu es while
he pa icipan comple ed i , hen called hem back s aigh away o con inue he in e iew.
I hey we e no able o submi he online consen o m because o echnological o li e acy
di icul ies, he s udy in o ma ion was ead ou loud o hem, he esea ch assis an illed ou
he o m, and an audio eco ding o he pa icipan ’s e bal consen was eco ded (22/95
pa icipan s).
Inclusion and exclusion c i e ia
Eligible pa icipan s we e: adul women; 18-69 yea s old; capable o p o iding in o med con-
sen ; able o unde s and and speak English o A ikaans, and no using p i a e heal hca e o
p i a e heal h insu ance. To be eligible as a p e ious p og am pa icipan , hey had a ended
a leas ou ou o six weekly sessions om one o he ou p e ious Wes e n Cape EBSA
p og ams. Con ols we e d awn om simila communi ies h ough nomina ion o he s udy
by a pa icipan o p og am communi y coach/ambassado . This is ypically how he p og am
ec ui s u u e p og am pa icipan s who a e ela i ely naï e o i s Low-Ca bohyd a e High-
Fa (LCHF) die a y ad ice.
Rec ui men
The ec ui men pe iod began 7 July 2020 and ended 28 Augus 2020. The educa o s and
communi y coaches we e asked o assis wi h ec ui ing women who we e en olled in p e ious
p og ams, ei he using he Wha sApp g oup o by elephone. Fo he non-p og am pa ic-
ipan s, a pe son iden i ied in he communi y was asked o help ec ui women and pa ici-
pan s we e also in i ed o nomina e a non-p og am woman o ake pa in he s udy. Those
women in e es ed in aking pa we e gi en he app op ia e pa icipan in o ma ion shee
(i.e., ea men o con ol) elec onically. Women we e no necessa ily expec ed o ead i bu
we e asked i hey would like a esea che o con ac hem o explain he s udy. Women who
communica ed hei in e es in ecei ing mo e in o ma ion abou he s udy we e con ac ed by
a membe o he esea ch eam. An in og aphic explaining he 10 s eps o comple e he s udy
was sen elec onically. A esea che explained he s udy, answe ed ques ions, sc eened o
eligibili y and in i ed in e es ed women o ake pa .
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PLOS ONE The impac o a low-ca bohyd a e nu i ion educa ion p og am on ood p e e ences
Da a sou ces and p ocessing
Supe ma ke pu chases
The pa icipan s each ecei ed a ZAR 250 (~13 USD) ouche ia SMS. A he ime o he
s udy, his amoun equa ed o abou a week’s ypical ood shopping in ou sample popula ion.
The shopping ac i i y was held a a majo local supe ma ke . Pa icipan s could choose om
a selec ion o esh p oduce and cupboa d g oce ies (a cu en e ail p ices). A membe o he
esea ch eam explained he ac i i y and conduc ed a demog aphic ques ionnai e. Each pa -
icipan had a week o pu chase he g oce ies a he con enience. An online shopping accoun
wi h which he ouche s we e pu chased allowed he in es iga o s o ack which ouche s
had been spen . Pu chasing decisions we e made p i a ely in he s o e. The pa icipan had
access o he phone o keep ack o he o al cos o he shopping. When she had inished
selec ing i ems, she p oceeded o he checkou . A home, she ook a pho o o bo h he g oce -
ies and he ill slip, and sen hem o he esea che . The esea che icked o on a checklis
wi h he pa icipan ’s code he ypes o oods she chose o buy and no ed he o al spen on he
eceip .
Nu i ion su ey
When he shopping ac i i y was comple ed, he ollow-up in e iew was booked, usually on
he same day o he ollowing day. Pa icipan s comple ed an in e iewe -adminis e ed FFQ
on a phone call wi h a membe o he esea ch eam and we e asked abou oods ea en in he
pas ou weeks. The FFQ was de eloped acco ding o guidelines [22] and he Sou h A ican
Medical Resea ch Council’s FFQ was adap ed o include ood i ems equen ly ea en by people
ollowing a Low-Ca bohyd a e High-Fa (LCHF) die and oods epo edly ea en by p e ious
p og am pa icipan s. I also included s anda d po ion sizes and equency op ions. I unde -
wen a pe iod o pilo es ing in olun ee s ha habi ually ollowed a LCHF die and was mod-
i ied acco dingly [23]. The FFQ da a we e p ima ily used o assess he ypes o oods ea en.
Da a cleaning and a iable ans o ma ion
The da a cleaning and analysis was conduc ed using S a a 15. To measu e a e age epo ed
die a y in ake, he FFQ asked esponden s how equen ly hey had ea en a s anda d po -
ion o a pa icula ood in he pas ou weeks. Fo example, “In he pas 4 weeks, how o en
did you ea a slice o whi e b ead?” o which he pa icipan could choose one o nine ixed
esponses, e.g., “None”, “1 o less pe mon h”, “2-3 pe mon h, “1-2 pe week”, 3-4 pe week”,
“5-6 pe week”, “1 pe day”, “2-3 pe day” o “3 o mo e pe day”. Fo he analysis, ca ego ical
a iables we e con e ed in o con inuous nume ical a iables, speci ically, an es ima e o he
numbe o s anda d po ions ea en pe week. e.g., i a pa icipan esponded “1 pe day”, his
was con e ed o “7 pe week”.
The ood pu chases ha he sample o women made wi h a e ail ouche we e coded as a
lis o dummy a iables. I a ood i em (e.g., b ead) was pu chased, his choice was cap u ed as
“1”, and “0” o he wise. The selec ed lis o oods co esponded o he EBSA p og am’s a ic
ligh s lis o oods (S1 Fig) as well as he FFQ i ems o ease o compa ison. P esen a ion o
he epo ed ood in ake and ood choices acco ding o he a ic ligh s lis s makes i s aigh -
o wa d o in e isually whe he he sample o women a e ea ing acco ding o he p og am’s
ecommenda ions.
Fi e o he con ol g oup’s obse a ions we e excluded om he analysis because hese
non-p og am women we e pa o a gym g oup un by an EBSA communi y coach (Fig 1) and
al eady ea ing acco ding o he p og am’s die a y guidelines (S1 Fig).
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PLOS ONE The impac o a low-ca bohyd a e nu i ion educa ion p og am on ood p e e ences
A RED index sco e was c ea ed ha added up he bina y ood choice a iables, wi h a max-
imum sco e o 8 i all Red Lis oods we e pu chased. An ORANGE index sco e added up he
ele an bina y ood choice a iables, wi h a maximum sco e o 3 i all h ee O ange Lis oods
we e pu chased. A GREEN index sco e added up he ele an bina y ood choice a iables,
wi h a maximum sco e o 8 i all eigh G een Lis oods we e pu chased.
Tes s and eg ession models
Indi idual cha ac e is ics we e examined o mo i a e ha he con ol g oup can be used
as a alid coun e ac ual o e alua e he impac o he p og am. The non-pa ame ic
K uskal-Wallis H es was conduc ed o es o signi ican di e ences (a he con en ional
signi icance h eshold o 5%) in he dis ibu ions o indi idual and household cha ac e is-
ics. The sel - epo die a y in ake o pa icipan s was ca ego ized in o he p og am’s Red,
O ange and G een a ic-ligh lis s. To e alua e he impac o he EBSA p og am wi h women
p esumably a emp ing o ollow he ecommended LCHF die , he ypes o oods ea en by
he con ol and ea men g oups we e compa ed. I he p og am in luenced ea ing habi s
acco ding o i s ecommenda ions, one would expec o see ewe Red Lis ood i ems and
mo e G een Lis i ems consumed by he ea men g oup compa ed o he con ol g oup. We
con olled o obse able cha ac e is ics in he O dina y Leas Squa es (OLS) eg ession anal-
ysis wi h obus s anda d e o s (which also used he con en ional h eshold o 5% o e alua e
signi icance). The ypes o ood pu chases o he ea men and con ol g oups we e com-
pa ed. In he Linea P obabili y Model (LPM) eg ession analysis, we con olled o obse -
able cha ac e is ics. Finally, we conside ed he co espondence be ween su eyed esponses
and pu chasing beha io , which allowed us o make an e alua ion o he alidi y o he FFQ.
I he FFQ esponses o ou sample co ela ed well wi h he incen i ized beha io al measu e
o ood p e e ences, his would suppo i s use as a alid ins umen o assess he impac o
he nu i ion educa ion p og am on women’s ood p e e ences, while i he wo ins umen s
di e ged his would unde mine he FFQ’s c edibili y.
Resul s
Sample cha ac e is ics
The ea men and con ol g oups we e balanced in e ms o household cha ac e is ics: num-
be o household membe s, numbe o employed household membe s, shopping equency
and ood insecu i y (S1 Table). Abou hal o all pa icipan s wo ied hey would no ha e
enough ood because o lack o money in he p eceding ou weeks. Table 1 shows ha he wo
g oups we e well balanced and simila on a numbe o obse able indi idual cha ac e is ics
as well. Acco ding o he mos ecen census conduc ed in 2022 he sample is ep esen a i e
o he e hnici y and language o ou wo Wes e n Cape communi ies [24]. I should be no ed,
howe e , ha he ea men g oup was signi ican ly olde (χ2(1) = 10.760, p = 0.001). The
mean age o he con ol g oup was abou 44 yea s old, while he mean age o he p o-
g am g oup was abou 51 yea s old. In he eg ession analysis, we con olled o obse able
cha ac e is ics.
Almos all he women had child en (mode: 2; max: 5), and 75% o he women sha ed he
household wi h a pa ne . The women we e usually esponsible o g oce ies (χ2(1) = 1.639, p
= 0.2005). On a e age, households had ou membe s, wi h one o wo membe s employed. A
highe p opo ion o he con ol g oup we e employed (53% compa ed o 32% (χ2(1) = 4.251,
p = 0.0392) bu he e was no signi ican di e ence be ween he wo g oups a he 5% le el in
he p opo ion o wo king-age indi iduals employed, χ2(1) = 2.833, p = 0.0924. In he pooled
sample, 43% had comple ed p ima y school only, 35% had comple ed high school and 21%
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PLOS ONE The impac o a low-ca bohyd a e nu i ion educa ion p og am on ood p e e ences
highe educa ion. The ea men g oup also had mo e pa icipan s whose highes le el o edu-
ca ion was p ima y school, and his di e ence was signi ican a he 5% le el, χ2(1) = 5.226,
p = 0.0222. Howe e , he e was no signi ican di e ence a he 5% le el be ween he g oups in
basic educa ion a ainmen (whe e p ima y school and high school a e pooled), χ2(1) = 3.378,
p = 0.0661. In Sou h A ica, he e u ns o educa ion a e con ex, in ha he ma ginal a e o
e u n is ex emely high o e ia y le els o educa ion and app oaches ze o o lowe le els o
educa ion [25]. Thus, comple ing school e sus no is a guably he mo e ele an cha ac e is-
ic wi h which o conside di e ences in li e chances be ween he wo g oups. The e we e no
signi ican di e ences be ween he g oups in non-communicable disease isk ac o s a he 5%
le el, howe e , he con ol g oup had a ma ginally lowe incidence o diagnosed high blood
p essu e a he 10% le el.
The posi i e e ec o he p og am on epo ed ood in ake in he pas ou
weeks
Fig 2 shows his og ams o o al weekly consump ion o s anda d po ions o oods o ganized
by he p og am’s a ic ligh s lis s o oods (S1 Fig) whe e, acco ding o he EBSA p og am,
he Red Lis is o be a oided, he O ange Lis o occasional consump ion, and he G een Lis
o be ea en libe ally. The Red Lis includes oods high in ca bohyd a es and seed oils such as
as ood, suga , b ead, pas a, po a oes. The O ange Lis includes ui , such as bananas and
apples. The G een Lis includes eggs, unp ocessed mea , unswee ened ull c eam dai y, g een
lea y ege ables. In each his og am, ligh e ba s indica e he dis ibu ion o he con ol g oup’s
esponses, da ke ba s indica e he dis ibu ion o he ea men g oup’s esponses, and da k-
es ba s show whe e he dis ibu ions o e lap. The ea men ’s o al weekly consump ion om
Table 1. Sample cha ac e is ics.
T ea men G oup Con ol (n = 51) T ea men (n = 44)
Age (yea s) 43.76 50.84 1
Li es wi h pa ne 75% 75%
Has child en 96% 93%
Buys household g oce ies 94% 86%
Wo k s a us
Employed 53% 32% 1
Employed & wo king age 43% 38%
Educa ion
No o mal schooling 0 2%
P ima y school 37% 55% 1
High school 37% 32%
College o Uni e si y 27% 9%
Pos -g adua e deg ee 2% 2%
Heal h isk ac o s
Smoke (daily) 12% 7%
Alcohol (pas yea ) 39% 41%
Ele a ed blood p essu e 33% 52%
Blood p essu e medica ion 16% 32%
Diabe es 12% 7%
CVD e en o ches pain 4% 14%
1Signi ican p- alue a he 5% le el in K uskal-Wallis H es s, which we e conduc ed as a balance check be ween con-
ol and ea men g oups., i.e., g oups we e unbalanced on his cha ac e is ic.
h ps://doi.o g/10.1371/jou nal.pone.0319503. 001
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PLOS ONE The impac o a low-ca bohyd a e nu i ion educa ion p og am on ood p e e ences
he Red Lis is clea ly le -shi ed compa ed o he con ol (i.e., ewe s anda d po ions o Red
Lis i ems we e consumed, K-Smi no es : T ea men <Con ol, p < 0.001). In con as , o
he G een Lis , he dis ibu ions a e e e sed in a o o he p og am (Con ol <T ea men ,
p < 0.001). In gene al, o he O ange Lis , he e is no much in e es ing a ia ion be ween
ea men and con ol. As we did no ha e pa icula hypo heses o he consump ion om
he O ange Lis , we ocus on he G een and Red Lis s in he main pape and epo he O ange
Lis esul s in S1 File supplemen a y ex , o comple eness.
Fig 3 shows coe icien plo s om OLS eg essions o he numbe o s anda d po ions pe
week on a bina y a iable = 1 i ea men , and 0 i con ol, as well as explana o y a iables
age and highes educa ion. Each eg ession coe icien illus a ed o igina es om a sepa a e
model. We modelled he e ec o pa icipa ing in he p og am on o al weekly in ake o Red,
O ange and G een Lis oods, espec i ely. The e ec on epo ed consump ion o pa icula
oods should be in e p e ed wi h cau ion because o mul iple hypo hesis es ing conce ns wi h
a sample o 95 women. The OLS models in Fig 3 conside ed only he FFQ da a. The co e-
sponding eg ession esul s a e epo ed in S2 Table. The ea men g oup epo ed signi i-
can ly ewe o al Red Lis po ions pe week, i.e., 56 in ea men e sus 86 in con ol, a 35%
educ ion in unheal hy ood by he ea men g oup, om he pe spec i e o he p og am.
Fig 2. O e iew o epo ed ood in ake in he pas ou weeks by he ea men and con ol g oup. His og ams indica e he dis i-
bu ion o ood in ake by a sample o women who ha e comple ed he EBSA p og am (n = 44) e sus simila women who a e eligible
o u u e p og ams in he communi y (n = 51). The da a a e ca ego ized by he low-ca b p og am’s a ic ligh s lis s o oods. See S1
Fig o de ailed G een, O ange and Red Lis s. Da ke colo ed ba s indica e he ea men g oup, while ligh e ba s indica e he con ol
g oup. The ea men g oup is signi ican ly di e en on Red and G een Lis , bu no O ange Lis (non-pa ame ic K-Smi no es s o
equali y o dis ibu ion: p < 0.001).
h ps://doi.o g/10.1371/jou nal.pone.0319503.g002
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PLOS ONE The impac o a low-ca bohyd a e nu i ion educa ion p og am on ood p e e ences
Au ho con ibu ions
Concep ualiza ion: So ia Mon ei o, Geo gina Pujol-Busque s, James Smi h, Ka e La mu h.
Da a cu a ion: So ia Mon ei o.
Fo mal analysis: So ia Mon ei o.
Funding acquisi ion: So ia Mon ei o.
In es iga ion: So ia Mon ei o, Ka e La mu h.
Me hodology: So ia Mon ei o, Geo gina Pujol-Busque s, James Smi h, Ka e La mu h.
P ojec adminis a ion: So ia Mon ei o, Ka e La mu h.
Resou ces: So ia Mon ei o.
So wa e: So ia Mon ei o.
Supe ision: Ka e La mu h.
Visualiza ion: So ia Mon ei o.
W i ing – o iginal d a : So ia Mon ei o.
W i ing – e iew & edi ing: So ia Mon ei o, Geo gina Pujol-Busque s, Ka e La mu h.
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