Empowerment-based nutrition interventions on blood pressure: a randomized comparative effectiveness trial

Abstract

Introduction
Empowerment lifestyle programs are needed to reduce the risk of hypertension. Our study compared the effectiveness of two empowerment-based approaches toward blood pressure (BP) reduction: salt reduction-specific program vs. healthy lifestyle general program.

Methods
Three hundred and eleven adults (median age of 44 years, IQR 34–54 years) were randomly assigned to a salt reduction (n = 147) or a healthy lifestyle program (n = 164). The outcome measures were urinary sodium (Na⁺) and potassium (K⁺) excretion, systolic (SBP) and diastolic (DBP) blood pressure, weight, and waist circumference.

Results
There were no significant differences in primary and secondary outcomes between the two program groups. When comparing each program to baseline, the program focused on salt reduction was effective in lowering BP following a 12-week intervention with a mean change of −2.5 mm Hg in SBP (95% CI, −4.1 to −0.8) and − 2.7 mm Hg in DBP (95% CI, −3.8 to −1.5) in the intention-to-treat (ITT) analysis. In the complete-case (CC) analysis, the mean change was −2.1 mm Hg in SBP (95% CI, −3.7 to −0.5) and − 2.3 mm Hg in DBP (95% CI, −3.4 to −1.1). This effect increases in subjects with high-normal BP or hypertension [SBP − 7.9 mm Hg (95% CI, −12.5 to −3.3); DBP − 7.3 mm Hg (95% CI, −10.2 to −4.4)]. The healthy lifestyle group also exhibited BP improvements after 12 weeks; however, the changes were less pronounced compared to the salt reduction group and were observed only for DBP [mean change of −1.5 mm Hg (95% CI, −2.6 to −0.4) in ITT analysis and − 1.4 mm Hg (95% CI, −2.4 to −0.3) in CC analysis, relative to baseline]. Overall, improvements in Na⁺/K⁺ ratio, weight, and Mediterranean diet adherence resulted in clinically significant SBP decreases. Importantly, BP reduction is attributed to improved dietary quality, rather than being solely linked to changes in the Na⁺/K⁺ ratio.

Conclusion
Salt-focused programs are effective public health tools mainly in managing individuals at high risk of hypertension. Nevertheless, in general, empowerment-based approaches are important strategies for lowering BP, by promoting health literacy that culminates in adherence to the Mediterranean diet and weight reduction.

Full text

Frontiers in Public Health 01 frontiersin.org
Empowerment-based nutrition
interventions on blood pressure: a
randomized comparative
eectiveness trial
AndréMoreira-Rosário
1,2*, ShámilaIsmael
1,2, 3,
InêsBarreiros-Mota
1,3, JulianaMorais
1,2, CatarinaRodrigues
1,3,
InêsCastela
1,2, 3, InêsCurveloMendes
4, MariaInêsSoares
4,
LuísSoaresdaCosta
4, CatarinaBatistaOliveira
4,
TiagoHenriques
4, PatríciaPinto
4, DéboraPita
4,
CatarinaMarquesdeOliveira
4, JanaínaMaciel
4, ThainaSerafim
4,
JoãoAraújo
1,2, JúlioCésarRocha
1,2, DiogoPestana
1,2,
MartaP.Silvestre
1,2, CláudiaMarques
1,2, AnaFaria
1,2, 3,
JorgePolonia
5,6, 7† and ConceiçãoCalhau
1,2†
1 NOVA Medical School, Faculdade de Ciências Médicas, NMS, FCM, Universidade Nova de Lisboa,
Lisbon, Portugal, 2 CINTESIS@RISE, NOVA Medical School, Faculdade de Ciências Médicas, NMS, FCM,
Universidade Nova de Lisboa, Lisbon, Portugal, 3 CHRC, NOVA Medical School, Faculdade de Ciências
Médicas, NMS, FCM, Universidade Nova de Lisboa, Lisbon, Portugal, 4 CUF Academic and Research
Medical Center, Lisbon, Portugal, 5 Department of Community Medicine, Information and Health
Decision Sciences (MEDCIDS), Faculty of Medicine, University of Porto, Porto, Portugal, 6 CINTESIS@
RISE, Faculty of Medicine, University of Porto, Porto, Portugal, 7 Hypertension and Cardiovascular Risk
Unit, Unidade Local de Saúde Matosinhos, Matosinhos, Portugal
Introduction: Empowerment lifestyle programs are needed to reduce the risk
of hypertension. Our study compared the eectiveness of two empowerment-
based approaches toward blood pressure (BP) reduction: salt reduction-specific
program vs. healthy lifestyle general program.
Methods: Three hundred and eleven adults (median age of 44 years, IQR 34–
54 years) were randomly assigned to a salt reduction (n = 147) or a healthy
lifestyle program (n = 164). The outcome measures were urinary sodium (Na+)
and potassium (K+) excretion, systolic (SBP) and diastolic (DBP) blood pressure,
weight, and waist circumference.
Results: There were no significant dierences in primary and secondary outcomes
between the two program groups. When comparing each program to baseline,
the program focused on salt reduction was eective in lowering BP following a
12-week intervention with a mean change of −2.5 mm Hg in SBP (95% CI, −4.1
to −0.8) and − 2.7 mm Hg in DBP (95% CI, −3.8 to −1.5) in the intention-to-treat
(ITT) analysis. In the complete-case (CC) analysis, the mean change was −2.1 mm
Hg in SBP (95% CI, −3.7 to −0.5) and − 2.3 mm Hg in DBP (95% CI, −3.4 to −1.1).
This eect increases in subjects with high-normal BP or hypertension [SBP −
7.9 mm Hg (95% CI, −12.5 to −3.3); DBP − 7.3 mm Hg (95% CI, −10.2 to −4.4)]. The
healthy lifestyle group also exhibited BP improvements after 12 weeks; however,
the changes were less pronounced compared to the salt reduction group and
were observed only for DBP [mean change of −1.5 mm Hg (95% CI, −2.6 to −0.4)
in ITT analysis and − 1.4 mm Hg (95% CI, −2.4 to −0.3) in CC analysis, relative
to baseline]. Overall, improvements in Na+/K+ ratio, weight, and Mediterranean
diet adherence resulted in clinically significant SBP decreases. Importantly, BP
OPEN ACCESS
EDITED BY
Zhendong Liu,
Shandong First Medical University, China
REVIEWED BY
Florencia Ceriani,
Universidad de la República, Uruguay
Federica Fogacci,
University of Bologna, Italy
*CORRESPONDENCE
André Moreira-Rosário
andre.rosario@nms.unl.pt
†These authors have contributed equally to this
work
RECEIVED 14 August 2023
ACCEPTED 27 October 2023
PUBLISHED 13 November 2023
CITATION
Moreira-Rosário A, Ismael S, Barreiros-Mota I,
Morais J, Rodrigues C, Castela I, Mendes IC,
Soares MI, da Costa LS, Oliveira CB,
Henriques T, Pinto P, Pita D, de Oliveira CM,
Maciel J, Serafim T, Araújo J, Rocha JC,
Pestana D, Silvestre MP, Marques C, Faria A,
Polonia J and Calhau C (2023) Empowerment-
based nutrition interventions on blood
pressure: a randomized comparative
eectiveness trial.
Front. Public Health 11:1277355.
doi: 10.3389/fpubh.2023.1277355
COPYRIGHT
© 2023 Moreira-Rosário, Ismael, Barreiros-
Mota, Morais, Rodrigues, Castela, Mendes,
Soares, da Costa, Oliveira, Henriques, Pinto,
Pita, de Oliveira, Maciel, Serafim, Araújo, Rocha,
Pestana, Silvestre, Marques, Faria, Polonia and
Calhau. This is an open-access article
distributed under the terms of the Creative
Commons Attribution License (CC BY). The
use, distribution or reproduction in other
forums is permitted, provided the original
author(s) and the copyright owner(s) are
credited and that the original publication in this
journal is cited, in accordance with accepted
academic practice. No use, distribution or
reproduction is permitted which does not
comply with these terms.
TYPE Clinical Trial
PUBLISHED 13 November 2023
DOI 10.3389/fpubh.2023.1277355

Moreira-Rosário et al. 10.3389/fpubh.2023.1277355
Frontiers in Public Health 02 frontiersin.org
reduction is attributed to improved dietary quality, rather than being solely linked
to changes in the Na+/K+ ratio.
Conclusion: Salt-focused programs are eective public health tools mainly in
managing individuals at high risk of hypertension. Nevertheless, in general,
empowerment-based approaches are important strategies for lowering BP, by
promoting health literacy that culminates in adherence to the Mediterranean diet
and weight reduction.
KEYWORDS
cardiovascular diseases, hypertension, blood pressure, mediterranean diet, sodium/
potassium ratio
1. Introduction
Changing unhealthy lifestyle behaviors can decrease the
prevalence of individuals with high blood pressure (BP) and
cardiovascular diseases (CVD), contributing greatly to the
sustainability of healthcare systems worldwide (1, 2). Current
guidelines for managing hypertension recommend the adoption of a
healthy diet as an integral part of disease treatment, regardless of
antihypertensive medication intake (2–4).
Several dietary approaches have been proposed to reduce BP,
including the Dietary Approaches to Stop Hypertension (DASH), the
low-salt diet, and the Mediterranean diet (5–9). Recent systematic
reviews of randomized controlled trials (RCTs) showed that dietary
approaches with low sodium (Na
+
) and high potassium (K
+
) intake,
such as DASH and low-salt diets, are eective in lowering BP (6, 7, 10).
DASH and low-salt diets promote the consumption of nutrients and
food components with antihypertensive properties such as minerals
(potassium, magnesium, and calcium), vitamins, phytochemicals,
polyphenols, unsaturated fatty acids, and ber (11). Otherwise, the
Mediterranean diet places greater emphasis on food groups and meals,
rather than isolated nutrients. It is characterized by its elevated
consumption of plant-based foods, such as fruits, vegetables, legumes,
and nuts, while relying on olive oil as the main fat source. e diet also
includes a moderate intake of sh and poultry and a reduced intake of
dairy products, red and processed meats, and whole-fat dairy products
(12). e protective eect of the Mediterranean diet against CVD has
also been extensively studied (13). When compared to the DASH diet,
the Mediterranean diet has demonstrated greater eectiveness in
reducing the risk of CVD, particularly within populations already
accustomed to these dietary and lifestyle practices (14).
However, in the context of preventing and treating hypertension,
dietary interventions are mostly assessed individually. Yet, recent
systematic reviews exploring both the DASH and Mediterranean diets
have revealed that the DASH diet shows the most convincing proof of
its ecacy in lowering BP (7, 8). Signicantly, despite these insights,
there has been no randomized trial so far that directly compares how
the DASH and Mediterranean diets dier in their eects on reducing BP.
Furthermore, some of these studies use controlled and specic
feeding methods to make sure participants stick to the planned diets.
is is veried through close monitoring of participants during
on-site meals, along with inquiries about their consumption of study
foods, and the collection of urine samples. Although it is important to
acknowledge that while these controlled scenarios play a critical role
in assessing ecacy, they may not precisely mirror how these ndings
would apply to the daily circumstances of the broader population.
In the realm of encouraging changes in behavior, empowerment-
based methods have emerged as powerful triggers, giving citizens the
freedom to steer their own choices toward healthier eating preferences
(15–19). However, despite its clear importance in improving health
and well-being, the concept of empowerment has unfortunately not
been used enough in programs designed to promote healthy dietary
habits (15, 16). According to the World Health Organization (WHO),
health promotion is a process that empowers individuals to have more
control over the decisions and actions that aect their well-being (20).
is broad and multifaceted view of health encompasses social,
economic, and environmental factors, all of which play crucial roles
in shaping daily health conditions (20, 21).
Hence, the driver to improve public health centers on spreading
health information grounded in evidence, raising awareness, and
empowering people to integrate personalized and suitable health-
conscious behaviors into their daily routines.
With this viewpoint in mind, we designed a randomized
comparative trial to thoroughly examine the eectiveness of two
empowerment-driven approaches. One of these strategies focused on
reducing salt intake, echoing the principles of the DASH diet, while
the other centered around fostering a holistic and all-encompassing
healthy lifestyle regimen. is latter approach incorporated guidance
aligned with the core principles of the Mediterranean dietary pattern.
ese educational eorts were carefully designed to enhance
participants’ understanding of benecial lifestyle practices. Moreover,
the programs provided participants with practical resources to help
them adopt new habits. is comprehensive toolkit encompassed
strategies for embracing wholesome cooking practices and making
well-informed choices when buying food. Essentially, our main goal
was to determine which of these empowerment-focused methods
would prove to bethe more eective driver in nurturing health-
oriented dietary habits and achieving reductions in BP across the
broader population.
2. Materials and methods
2.1. Study design
is study is a multicenter, randomized, comparative eectiveness
trial comparing the outcomes of two dierent 12-week

Moreira-Rosário et al. 10.3389/fpubh.2023.1277355
Frontiers in Public Health 03 frontiersin.org
empowerment-based approaches to promote healthy habits in the
general population. e trial was conducted between March 2019 (the
rst candidate screened for eligibility) and September 2019 (the end
of the 12-week follow-up of the last participant), aer obtaining
approval from the Ethical Committee of the Hospital CUF on
December 18, 2018, for the project. e study was conducted in
accordance with the ethical principles of the Declaration of Helsinki
and followed the Good Clinical Practice guidelines. All enrolled
participants provided voluntary, written informed consent. e
present study adhered to the CONSORT reporting guidelines
(Supplementary Table S1) and was registered on the ClinicalTrials.gov
database (NCT03830021).
2.2. Participants
e study enrolled adult participants aged 20 to 70, who were
responsible for acquiring and preparing their own meals, normal or
with hypertension. Medicated hypertense individuals were included
if medication and diet was stable for at least 3 weeks before the study.
Eligible participants had to bewilling and able to comply with the
study protocol and provide informed consent. Exclusion criteria
included a history of cardiovascular disease (such as ischemic
cardiovascular disease, stable or unstable angina, myocardial
infarction, stroke, or symptomatic peripheral arteriosclerosis), liver or
kidney diseases, or cancer. Participants were also excluded if they were
pregnant or breastfeeding women, women planning to become
pregnant within the study period, had a history of drug, alcohol, or
other substance abuse, or had other factors that might limit their
ability to cooperate during the study.
2.3. Recruitment
Participants were recruited from the Lisbon Metropolitan Area
through public advertisements in online newspapers and social media.
Participants underwent eligibility screening and assessment at the
study centers, which included the Hospital CUF Descobertas and
Hospital CUF Infante Santo. Eligible participants were randomly
assigned to one of two intervention groups (in a 1:1 ratio) using a
computer-generated allocation sequence. e allocation was
concealed through sequentially numbered, opaque, sealed envelopes.
e allocation sequence was generated by a statistician who was not
involved in recruitment or intervention delivery, ensuring that the
allocation process was objective and unbiased. To maintain participant
masking, the interventions were administered on dierent schedules,
and participants were kept unaware of their assigned interventions.
2.4. Interventions
2.4.1. Salt-reduction program
Participants randomized to the salt reduction program received a
multi-component educational program for 12 weeks, consisting of
three educational sessions that occurred during clinic visits (baseline,
4-week, and 8-week), ve individual practical training sessions at the
local supermarket, and 8 telephone counseling calls. During the initial
educational session, participants received information regarding salt
consumption, the health implications of excessive salt intake, and the
foods they should avoid to reduce their salt intake. In the subsequent
session, participants were educated on how to decipher food labels,
make choices that have lower salt content within the same food group,
and understand the signicance of substituting salt with herbs and
spices. In the nal session, participants were enlightened about
interpreting salt-related nutritional claims and the importance of
meeting recommended fruit and vegetable intake. Additionally, the
impact of potassium, calcium, and magnesium on BP was discussed,
along with the identication of optimal dietary sources for these
minerals. Following each session, participants were provided with an
informational yer covering the discussed topics. Participants in the
salt reduction group benetted from practical educational sessions
conducted within supermarkets, facilitating the application of the
acquired knowledge during the purchasing process. To further solidify
the information transmitted during in-person education, telephone
counseling calls were implemented between sessions.
2.4.2. Healthy lifestyle program
Participants randomized to the healthy lifestyle program received
a 12-week educational program that consisted of three sessions during
clinic visits (at baseline, 4-weeks, and 8-weeks) and 12 telephone
counseling calls. e rst session focused on the impact of the
Mediterranean diet on health, with an emphasis on cardiovascular
health. It included recommendations on the best food choices and
foods to avoid as part of the principles of the Mediterranean food
pattern. e second session addressed various lifestyle topics, such as
the importance of hydration, how to increase water intake, physical
activity, and sleep quality. e third session focused on the negative
health impact of addictive habits, such as alcohol consumption and
smoking, as well as healthy culinary methods. Aer each session,
participants received a yer summarizing the topics discussed.
Furthermore, they received four telephone counseling calls aer each
face-to-face session to reinforce the information and clarify any
questions or doubts.
2.5. Outcome assessment
We collected 24-h urine samples at baseline and aer the 12-week
intervention period to estimate Na
+
and K
+
excretion. Secondary
outcome measures including oce BP, anthropometric
measurements, and additional covariates (namely adherence to the
Mediterranean diet), were measured at baseline and during follow-up
at 4, 8, and 12 weeks (Figure1). Participants were instructed on how
to collect 24-h urine samples. Na
+
and K
+
in the urine were measured
using ame photometry, and creatinine was measured using an
automated validated enzymatic method at an authorized Clinical
Analysis Laboratory (Centro de Medicina Laboratorial Germano de
Sousa). Weassessed the adequacy of collection based on the expected
normal range of creatinine excretion, as previously described by
Brenner and Rector (22). Since a large proportion of urinary samples
fell outside the expected creatinine ranges, indicating inadequate
urine collections, weused Tanaka formulas to estimate 24-h urinary
Na
+
and K
+
excretion (23). We estimated salt intake from 24-h
urinary sodium excretion as 1 mEq/24 h Na
+
= 0.058 g per day salt.
Oce BP measurements were performed according to the guidelines
of the European Society of Hypertension/European Society of

Moreira-Rosário et al. 10.3389/fpubh.2023.1277355
Frontiers in Public Health 04 frontiersin.org
Cardiology (24), using Omron M7 (HEM-780-E) oscillometric
automated BP monitoring devices. ese devices were purposefully
acquired for their rst use in the trial. ese devices have been
rigorously validated and achieved an ‘A/A’ performance classication
under the British Hypertension Society (BHS) and Association for
the Advancement of Medical Instrumentation (AAMI) SP10
requirements (25). Anthropometric measurements were performed
according to the Directorate-General for Portuguese Health protocol
for body weight, height, and waist circumference (26). Trained
nutritionists, following a standardized protocol and strict quality
control procedures, conducted both the BP and anthropometric
measurements, including body weight, height, and waist
circumference, during face-to-face clinic visits at Hospital CUF
Descobertas and Hospital CUF Infante Santo. Within our Standard
Operating Procedures (SOP), wediligently considered the following
key factors regarding BP measurements: 1. Controlled the
temperature of the clinical cabinet, maintaining it between 18 and
22°C; 2. Instructed and controlled the participants, ensuring they
refrained from smoking or consuming stimulants such as coee at
least 60 min before the visit; 3. Allowed the participants to rest briey
FIGURE1
Flow diagram portraying the study design.

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Frontiers in Public Health 05 frontiersin.org
before BP measurement; 4. Ensured that the participants positioned
their supported measurement arm horizontally at the height of the
heart during measurements; 5. Instructed the participants to place
the sleeve of their shirt folded between the shoulder and the elbow,
without exerting pressure on the arm and keeping their legs slightly
open; 6. Enforced silence during BP measurements; 7. Conducted BP
measurements in both arms during the recruitment visit, noting the
arm with consistently higher pressure for subsequent visits; 8. At each
appointment, BP was measured twice. If a signicant discrepancy was
observed between the initial measurements, a third measurement was
taken into consideration. e questionnaire was used to collect
relevant covariates, including socio-demographic and health
information, dietary assessment, medication, smoking status, and
protocol compliance. Adherence to the Mediterranean diet was
evaluated using a previously validated 14-item questionnaire, known
as the PREDIMED Mediterranean Diet Adherence Screener
(MEDAS) (27). e MEDAS score was categorized as having the
lowest adherence (score 0–5), average adherence (score 6–9), and
highest adherence (score ≥ 10), as is commonly reported in the
literature (28–30). e assessment of salt content in food purchased
was not performed, as planned, due to a delay in the authorization
from the grocery company.
2.6. Statistical analysis
e sample size calculation was based on the estimated dierence
in salt reduction between the two groups aer 12 weeks. Assuming a
salt reduction of 1 g/day and a standard deviation of 3.8 g/day (22), a
sample size of 500 participants (250 per group) was calculated to
provide 80% power at a 5% level of signicance (two-sided) while
taking into account a 10% dropout rate.
Descriptive statistics were reported as numbers and percentages
for categorical variables and as mean and standard deviation for
continuous variables, or median and interquartile ranges if the
variable’s distribution was skewed. Between-group dierences at
baseline were assessed using appropriate tests such as the independent
sample t-test, Mann–Whitney U test, or chi-squared test.
e eect of the intervention on changes in BP, 24-h urinary
excretion of Na+ and K+, and anthropometry measurements such as
weight, BMI, and waist circumference were assessed using ANCOVA
with treatment group as the predictor and study center, age, sex,
baseline antihypertensive medications, baseline systolic BP value,
participant program protocol compliance, and smoking status as
covariates. Protocol compliance was evaluated based on adherence to
the sessions aimed to improve health literacy, as our primary goal was
to empower participants and then, assess the eectiveness of two
programs for salt reduction. To quantify participants’ adherence to the
study protocol, weestablished a scoring system, and the score value
was taken into consideration in the ANCOVA model. To manage
missing data, multiple imputation was performed for intention-to-
treat (ITT) analysis, using the chained equations approach with 5
imputed datasets and 10 iterations, and the results were pooled using
Rubin’s rule (31). Sensitivity analyses were carried out to assess the
robustness of the multiple imputation method by comparing the
distribution plots of recorded values with imputed values. All analyses
were conducted using SPSS version 27 soware (SPSS Inc., Chicago,
IL, UnitedStates).
3. Results
3.1. Recruitment and baseline
characteristics of the participants
From March 29 to June 4, 2019, a total of 352 candidates were
screened for eligibility. Aer an initial assessment, 30 declined to
participate and 11 did not meet the inclusion criteria. us, 311
participants were enrolled, comprising 224 women and 87 men with
a median age of 44 years (IQR 34–54 years), who were randomly
assigned to either a salt reduction-focused program (n = 147) or a
healthy lifestyle program (n = 164; see Figure1).
e study ended before the estimated 500 participants were
recruited due to lower than anticipated recruitment rates. All
participants contributed to baseline data and their characteristics are
shown in Table1, according to the intervention group. e proportion
of women was higher in the healthy lifestyle group (78.0% vs. 65.3%,
p = 0.012), but demographic and clinical characteristics were otherwise
balanced across the groups. e healthy lifestyle group had a slightly
higher proportion of participants who withdrew from the study
(15.2% vs. 10.2%, p = 0.185); the lack of time or motivation was the
most frequent reason for discontinuation in both groups. None of the
participants reported adverse eects.
Most participants were white Europeans (92.6%), professionally
active (81.0%), and had a university degree (74.9%). Additionally, over
half were overweight or obese (61.4%) and had an average adherence
to a Mediterranean diet (67.2%) at baseline. Two-thirds of the
participants had a family history of hypertension, dyslipidemia, or
CVD (66.9%), while almost one-fourth had dyslipidemia (26.0%). At
study entry, 17.0% of participants reported having hypertension, and
22.5% were taking antihypertensive medication. At baseline, the mean
systolic/diastolic BP was 116/76 (SD 15/10) mmHg, and the estimated
mean 24-h urinary Na+ excretion was 156.3 (SD 24.9) mmol/day.
e study’s primary and secondary outcome measures are
presented in Table2. To evaluate the eectiveness of the interventions,
both intention-to-treat (ITT) and complete-case (CC) analyses were
conducted. e ITT analysis included all participants who were
randomized and is considered the most reliable method of analysis,
while the CC analysis only included participants who completed the
study and may overestimate the intervention’s eectiveness. By
presenting results from both the ITT and CC analyses, weprovide a
more comprehensive understanding of the intervention’s eectiveness,
accounting for both ideal and real-world scenarios. is approach
ensures that the study’s ndings are robust and applicable to
clinical practice.
Aer the 12-week intervention, there were no signicant
dierences observed between the salt reduction-focused and healthy
lifestyle programs regarding predicted 24-h urinary Na
+
and K
+
excretion, as well as systolic and diastolic blood pressure (SBP and
DBP), weight, and waist circumference. Nonetheless, the salt
reduction program led to noteworthy enhancements in BP compared
to baseline, with a mean change of −2.5 mm Hg in SBP (95% CI, −4.1
to −0.8) and − 2.7 mm Hg in DBP (95% CI, −3.8 to −1.5) in the
intention-to-treat (ITT) analysis, while −2.1 mm Hg in SBP (95% CI,
−3.7 to −0.5) and − 2.3 mm Hg in DBP (95% CI, −3.4 to −1.1) in the
complete-case (CC) analysis. Notably, the healthy lifestyle group also
exhibited BP improvements aer 12 weeks; however, these were less
pronounced compared to the salt reduction group and were observed

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Frontiers in Public Health 06 frontiersin.org
only for DBP [mean change of −1.5 mm Hg (95% CI, −2.6 to −0.4) in
ITT analysis and − 1.4 mm Hg (95% CI, −2.4 to −0.3) in CC analysis,
relative to baseline].
e reduction in BP within the groups may beattributed to the
enhancement in predicted 24-h K
+
excretion aer the 12-week
intervention compared to baseline. is positive trend was observed
in both groups during the ITT, with a mean change of 2.1 mmol/24 h
(95% CI, 0.9 to 3.3) for the healthy lifestyle group and 1.4 mmol/24 h
(95% CI, 0.1 to −2.6) for the salt reduction group. In the CC analysis,
this improvement was relatively smaller, achieving statistical
signicance solely within the healthy lifestyle group at 1.9 mmol/24 h
(95% CI, 0.6 to 3.2).
3.2. Impact of intervention on blood
pressure
Aer 4 weeks, both the salt reduction and healthy lifestyle
programs led to lower SBP compared to baseline: −1.7 mm Hg (95%
CI, −3.1 to −0.3) for the salt reduction and − 1.5 mm Hg (95% CI,
−2.8 to −0.2) for the healthy lifestyle. Importantly, the salt reduction
group maintained lower SBP at 8 and 12 weeks, unlike the healthy
lifestyle group (Figure2A). Both groups showed DBP improvement
aer 12 weeks (Figure2B). Moreover, there were no signicant sex
dierences in BP outcomes (data not shown).
In participants with high-normal or hypertension (SBP ≥ 130 and/
or DBP ≥ 85, mm Hg; n = 32in the healthy lifestyle group and n = 30in
the salt reduction group), a subgroup analysis revealed signicant BP
reduction aer 12 weeks within the salt reduction group: SBP
decreased by −7.9 mm Hg (95% CI, −12.5 to −3.3), and DBP
decreased by −7.3 mm Hg (95% CI, −10.2 to −4.4). Furthermore,
notable dierences between the groups were observed at week 8in
both SBP [−6.8 mm Hg (95% CI, −12.8 to −0.7), p = 0.029] and DBP
[−4.6 mm Hg (95% CI, −8.6 to −0.6), p = 0.025]. Interestingly, a
signicant between-group dierence in DBP was also evident at the
end of the 12-week intervention [−4.4 mm Hg (95% CI, −8.7 to −0.2),
p = 0.041], favoring the salt reduction program (Figures2C,D).
3.3. Impact of Na+/K+ ratio on blood
pressure
Participants were categorized into quintile groups (Q1 to Q5)
based on changes in the 12-week Na+/K+ ratio relative to the baseline
for each program. e quintile groups represent the range of changes
from lowest to highest. e variations in BP across these quintile
groups are shown in Figure3.
While not reaching statistical signicance, these ndings suggest
that a lower Na
+
/K
+
ratio tends to correspond with a reduction in
mean SBP variation. is reduction ranges from −1.9 mm Hg (95%
CI, −5.1 to 1.4) to −4.8 mm Hg (95% CI, −8.7 to −0.6) for the salt
reduction program, and from 0.6 mm Hg (95% CI, −2.8 to 3.9) to
−2.6 mm Hg (95% CI, −6.2 to 0.9) for the healthy lifestyle program,
when comparing the lowest (Q1) to the highest (Q5) quintiles. is
observed tendency remains consistent even when considering
participants with high-normal or hypertension at baseline, as
illustrated in Figure3C. Notably, within this subgroup, the slope is
more pronounced in the salt reduction group, ranging from −2.1 mm
TABLE1 Baseline demographic and clinical characteristics of participants
by randomized group.
Characteristic Salt
reduction
program
(n = 147)
Healthy
lifestyle
program
(n = 164)
P
value
Age, y 44 [34–52] 44 [35–55] 0.688
Sex, female 96 (65.3%) 128 (78.0%) 0.012
Ethnicity
White/European 137 (93.2%) 151 (92.1%)
0.842
White/African or South American 6 (4.1%) 7 (4.3%)
Black 1 (0.7%) 3 (1.8%)
Mixed 3 (2.0%) 3 (1.8%)
Weight, kg 75.6 (14.3) 74.5 (18.2) 0.570
BMI, kg/m227.1 (4.7) 27.6 (6.0) 0.430
Overweight/Obese (≥25 BMI) 92 (62.6%) 99 (60.4) 0.688
Waist circumference, cm 85.7 (11.9) 85.0 (15.5) 0.649
Smoking status
Current smoker 19 (12.9%) 23 (14.0%) 0.761
Former smoker 29 (19.7%) 37 (22.6%)
Married or cohabiting 126 (85.7%) 132 (80.5%) 0.221
Professionally active 124 (84.4%) 128 (78.0%) 0.157
Education
University 111 (75.5%) 122 (74.4%) 0.820
Secondary or lower 36 (24.5%) 42 (25.6%)
Self-reported medical disorders
Hypertension 25 (17.0%) 28 (17.1%) 0.988
Diabetes 4 (2.7%) 2 (1.2%) 0.336
Dyslipidemia 39 (26.5%) 42 (25.6%) 0.853
Hypothyroidism 3 (2.0%) 10 (6.1%) 0.074
Hyperthyroidism 1 (0.7%) 4 (2.4%) 0.218
Family history of hypertension,
dyslipidemia, or CVD 99 (67.3%) 109 (66.5%) 0.869
MEDAS, score
Low adherence (score ≤ 5) 26 (17.7%) 24 (14.6%)
0.511Average adherence (score 6–9) 94 (63.9%) 115 (70.1%)
High adherence (score ≥ 10) 27 (18.4%) 25 (15.2%)
Oce measurements
Systolic blood pressure, mm Hg 116.1 (15.0) 115.4 (15.5) 0.670
Diastolic blood pressure, mm Hg 75.1 (9.9) 76.0 (9.1) 0.446
Heart rate, beats per minute 71.7 (11.0) 73.8 (10.2) 0.088
Urinary excretion (Tanaka prediction)
Sodium, mmol/24 h 157.2 (26.3) 155.6 (23.8) 0.572
Potassium, mmol/24 h 48.6 (6.7) 47.9 (6.7) 0.384
Salt intake estimated, g/d 9.2 (1.5) 9.1 (1.4) 0.572
Antihypertensive medications 29 (19.7%) 41 (25.0%) 0.125
Data are number of participants (%), mean (standard deviation), and median (interquartile
range). CVD, cardiovascular diseases; BMI, body mass index; BP, blood pressure. p values
were calculated using independent samples t test, Mann–Whitney U test or chi-squared test
as appropri ate.

Moreira-Rosário et al. 10.3389/fpubh.2023.1277355
Frontiers in Public Health 07 frontiersin.org
Hg (95% CI, −7.7 to 3.4) to −11.1 mm Hg (95% CI, −25.3 to 3.1),
whereas the healthy lifestyle group displays a modest decrease from
−1.0 mm Hg (95% CI, −12.0 to 9.9) to −3.6 mm Hg (95% CI, −9.7
to 2.6).
3.4. Impact of weight and adherence to the
mediterranean diet on blood pressure
For each program, participants were divided into Q1 to Q5
quintile groups based on weight changes aer 12 weeks compared to
baseline (lowest to highest change). Wethen analyzed how changes in
SBP and DBP related to these weight quintile groups (shown in
Figures4A,B). Results indicate that higher SBP reductions are linked
with greater weight loss, particularly in the higher weight reduction
quintiles (Figure 4A). Notably, participants in the highest weight
change quintile (Q5) experienced a − 3.1 mm Hg reduction in SBP for
both programs. However, this trend is more pronounced in the
healthy lifestyle group (Figure 4A). Importantly, a signicant
dierence in SBP is observed in the healthy lifestyle group when
comparing Q1 and Q5 quintile groups [6.2 mm Hg (95% CI, 0.0 to
12.4), p = 0.048].
Adherence to the Mediterranean diet was assessed using a well-
established 14-item questionnaire known as the Mediterranean
Diet Adherence Screener (MEDAS). Based on MEDAS scores,
there was a noteworthy increase in mean adherence to the
Mediterranean diet within both groups aer the 12-week period:
0.9 (0.6 to 1.2, p = 0.001) for the salt reduction program and 0.8
(0.5 to 1.1, p = 0.001) for the healthy lifestyle program (data not
shown). ese changes in score seemed to bedriven by increased
intake of specic dietary components, namely vegetables, fruits,
sh or seafood, tree nuts, and dishes seasoned with sofrito (sofrito
is a seasoning blend commonly used in Mediterranean cuisine,
made with chopped onions, garlic, and other aromatic ingredients
sautéed with olive oil). Simultaneously, there was a decrease in the
consumption of red or processed meats, butter, cream, margarine,
soda drinks, sweets, and confectionery (Supplementary Figure S1).
Moreover, no dierences between-group were observed in terms
of the total MEDAS score or between specic dietary components
(data not shown).
Subsequently, participants were categorized into quintile groups
based on the extent of their changes in adherence to the Mediterranean
diet following the 12-week follow-up in comparison to their baseline
measurements (Figures4C,D); the stratication was done for each
TABLE2 Mean dierence in outcome measures after 12 weeks.
Complete-case Intention-to-treat
Salt reduction
program (n = 132)
Healthy lifestyle
program (n = 139)
P value
between
groups
Salt reduction
program (n = 147)
Healthy lifestyle
program (n = 164)
P value
between
groups
n
Mean
change from
baseline
(95% CI)
n
Mean
change
from
baseline
(95% CI)
n
Mean
change
from
baseline
(95% CI)
n
Mean
change
from
baseline
(95% CI)
Oce measurements
Systolic blood
pressure, mm Hg 131 −2.5 (−4.1, −0.8)*138 −1.1 (−2.8, 0.5) 0.263 147 −2.1 (−3.7, −0.5)*164 −0.7 (−2.3, 0.9) 0.237
Diastolic blood
pressure, mm Hg 131 −2.7 (−3.8, −1.5)*138 −1.4 (−2.4, −0.3)*0.107 147 −2.3 (−3.4, −1.1)*164 −1.5 (−2.6,
−0.4)*0.330
Heart rate, beats
per minute 131 −2.1 (−3.7, −0.6)*138 −1.6 (−3.1, −0.1)*0.655 147 −1.8 (−3.3, −0.3)*164 −1.6 (−3.1,
−0.2)*0.873
Urinary excretion (Tanaka prediction)
Sodium,
mmol/24 h 132 0.0 (−4.8, 4.8) 139 −1.1 (−5.8, 3.6) 0.754 147 0.1 (−4.4, 4.6) 164 −0.4 (−4.6, 3.9) 0.880
Potassium,
mmol/24 h 132 1.1 (−0.3, 2.4) 139 1.9 (0.6, 3.2)*0.413 147 1.4 (0.1, 2.6)*164 2.1 (0.9, 3.3)*0.400
Salt intake
estimated, g/d 132 0.0 (−0.3, 0.3) 139 −0.1 (−0.3, 0.2) 0.754 147 0.0 (−0.3, 0.3) 164 0.0 (−0.3, 0.2) 0.880
Sodium/
potassium ratio 132 0.0 (−0.1, 0.1) 139 −0.1 (−0.2, 0.0) 0.321 147 0.0 (−0.1, 0.0) 164 −0.1 (−0.2, 0.0) 0.719
Weight, kg 131 −0.3 (−0.7, 0.0) 138 −0.3 (−0.7, 0.0) 0.965 147 −0.5 (−1.5, 0.4) 164 −0.3 (−1.2, 0.7) 0.698
BMI, kg/m2131 −0.1 (−0.2, 0.1) 138 −0.1 (−0.2, 0.1) 0.813 147 −0.2 (−0.6, 0.2) 164 −0.1 (−0.5, 0.3) 0.831
Wai st
circumference,
cm
131 0.0 (−0.7, 0.7) 135 −0.3 (−1.0, 0.4) 0.539 147 −0.1 (−1.3, 1.0) 164 0.2 (−0.9, 1.3) 0.696
Values are mean (95% CI). ANCOVA models were adjusted for study center, age, sex, antihypertensive medications, baseline systolic blood pressure value, participant program protocol
compliance and smoking status. *p value is statistically signicant.

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intervention program. is analysis demonstrates that participants
who exhibited the most signicant shi toward adherence to the
Mediterranean diet experienced a modest yet noticeable reduction in
SBP within both programs.
Furthermore, an investigation was undertaken to explore the
relationship between Na+/K+ ratios and enhanced adherence to the
Mediterranean diet (Supplementary Table S2). As anticipated,
individuals with the highest adherence to the Mediterranean diet
(MEDAS score ≥ 10) exhibited a notably lower mean Na+/K+ ratio, in
comparison to both the average MEDAS score (p = 0.031) and t he
lowest adherence group (p = 0.009, Supplementary Table S2). is
comparison suggests that the reduction in the Na
+
/K
+
ratio is
associated with adherence to the intervention programs, which, in
turn, corresponds with adhering to the Mediterranean diet.
4. Discussion
In the broader eort to address the impact of high BP and CVD
across populations, there is a pressing need to establish eective
strategies for encouraging behavior changes (1, 2). However,
implementing these strategies is challenging for healthcare
professionals. us, weconducted a randomized trial to assess the
impact of two distinct empowerment-focused approaches on dietary
habits and BP, as endorsed by clinical nutrition experts. Our goal was
to identify key factors in lifestyle adjustments that contribute to
successful BP reduction. To achieve this, wecompared a salt reduction
program with a holistic healthy lifestyle approach.
Our ndings revealed that both interventions were eective in
reducing DBP aer 12 weeks. However, only the intervention focused
on salt reduction was signicantly eective in decreasing SBP, with a
substantial mean reduction of −2.5 mm Hg aer 12 weeks compared
to baseline. Furthermore, the salt reduction program was more
eective at reducing BP in participants with high-normal or
hypertension at baseline (SBP ≥ 130 and/or DBP ≥ 85, mm Hg;
Figure 5). is highlights the notion that customizing
recommendations to address specic public health concerns, such as
hypertension, can lead to a more pronounced impact, especially
within risk groups ese results are in line with recent systematic
reviews that emphasize the superior ecacy of both the DASH and
low-salt diet in lowering BP when compared to the Mediterranean diet
(6–8, 10). However, it is crucial to emphasize that while distinctions
were noticeable, especially among participants with high-normal BP
or hypertension, there were no statistically signicant dierences
observed across all study participants.
e magnitude of our results in a short period is outstanding and
consolidates the importance of diet and nutrition in the management
of hypertension, independently of pharmacology. Because BP decrease
is semilogarithmic associated with the incidence of cardiovascular
outcomes, even a minor reduction has signicant benets (7).
Undeniably, this improvement in BP is highly relevant since previous
studies demonstrated that even a 2 mmHg reduction in SBP and DBP
FIGURE2
Change in oce blood pressure (BP) from baseline to 4, 8 and 12 weeks in the complete-case population. All participants from salt reduction and
healthy lifestyle groups were included in the analysis of systolic BP (A) and diastolic BP (B). Subgroup analysis of participants with high-normal or
hypertension at baseline (SBP ≥ 130 and/or DBP ≥ 85, mm Hg; n = 32in the healthy lifestyle group and n = 30in the salt reduction group) were also
included in the analysis of systolic BP (C) and diastolic BP (D). Data are presented as mean (95% CI), adjusted for study center, age, sex, antihypertensive
medications, baseline systolic blood pressure value, participant program protocol compliance and smoking status (ANCOVA). *p value is statistically
significant.

Moreira-Rosário et al. 10.3389/fpubh.2023.1277355
Frontiers in Public Health 09 frontiersin.org
is associated with 10% lower stroke-related mortality and with a 7%
lower risk of coronary artery disease (6). Likewise, 2 mmHg reduction
in SBP substantially reduced the risk of CVD (27 events for coronary
heart disease, 24 events for stroke, and 41 events for heart failure per
100,000 person-years) (32).
Nevertheless, it was somewhat surprising that the interventions
yielded no signicant impact on Na
+
and K
+
concentrations. It is
noteworthy to emphasize that our study design involved participants
attending dietary educational sessions, resembling intervention
studies focused on the Mediterranean diet (8), as opposed to the
controlled feeding protocols seen in DASH trials (7). is suggests
that the reduced BP is more likely a result of an overall improvement
in dietary quality rather than changes in the Na
+
/K
+
ratio, as previously
emphasized (9).
Indeed, the observed decrease in BP in our study can beattributed
to the intentional behavior changes adopted by participants over the
12-week intervention period. Specically, participants increased their
consumption of vegetables, fruits, sh, tree nuts and dishes seasoned
with sofrito, while reducing their intake of processed meats, butter,
margarine, and high-sugar products. Signicantly, these dietary
changes comprise benecial food ingredients that could account for
the observed decrease in BP. Notably, the presence of vitamins and
avonoids in vegetables and fruits might induce blood vessel
relaxation, driven by their antioxidant and anti-inammatory
properties (33). Similarly, sh consumption, attributed to its long-
chain n-3 polyunsaturated fatty acids, is associated with a moderate
reduction in BP, possibly by enhancing vascular reactivity and
endothelial function (34). e diverse range of nutrients in nuts,
including polyunsaturated fatty acids, magnesium, and antioxidants,
could potentially confer a favorable impact on BP (35). Importantly,
the olive oil within sofrito is rich in bioactive phenolic compounds
that may enhance endothelial function by increasing nitric oxide
availability and triggering vasodilation (36).
Furthermore, these dietary modications yielded improvements
in various anthropometric measures, ultimately contributing to the
reduction in BP. While variations in body measurements did not result
in a signicant mean dierence, a noticeable trend toward weight
reduction was apparent. It is worth noting that weight loss constitutes
a signicant lifestyle factor in the prevention and management of
hypertension, oen inuenced by dietary choices and physical activity
(37). Importantly, our clinical trial indicates that participants who
achieved more substantial weight reduction within the highest
quintiles also observed greater reductions in BP. Interestingly, the
slope of this trend was more pronounced in the healthy lifestyle group.
Nevertheless, both groups reduced −3.1 mm Hg SBP in the highest
quintiles of weight change. ese ndings corroborate a recent
systematic review and meta-analysis (11), indicating that larger
variations in body weight are associated with a more pronounced
FIGURE3
Change in oce blood pressure (BP) stratified by mean quintiles of changes in Na+/K+ ratio, after 12-week follow-up. Complete-case participants from
salt reduction and healthy lifestyle groups were included in the analysis of systolic BP (A) and diastolic BP (B). Subgroup analysis of participants with
high-normal or hypertension at baseline (SBP ≥ 130 and/or DBP ≥ 85, mm Hg) were also included in the analysis of systolic BP (C) and diastolic BP (D).
Data are presented as mean (SEM). Significance between Q1 to Q5 quintile subgroups was assessed by one-way analysis of variance (ANOVA)
corrected with Bonferroni test for multiple comparisons. Dierences in the same quintile between salt reduction and healthy lifestyle groups were
assessed by independent t test.

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Frontiers in Public Health 10 frontiersin.org
impact on BP. Similarly, a comprehensive dose–response meta-
analysis (38) revealed that each 1 kg of weight loss corresponds to an
approximate 1 mmHg reduction in SBP.
As expected, participants who achieved the largest reductions in
Na
+
/K
+
ratio exhibited a trend toward lower SBP, especially among
individuals with high-normal or hypertension at baseline, although
the results did not attain statistical signicance. Importantly, following
the 12-week intervention, participants with the highest adherence to
the Mediterranean diet exhibited a signicantly lower mean Na+/K+
ratio. is was expected since increased urinary K
+
excretion is
associated with a higher intake of vegetables and fruit, whole grains,
low-fat dairy products, sh, and poultry, all endorsed in the
Mediterranean diet. Likewise, lower excretion is associated with an
unhealthy diet, including calorie-dense foods such as fast food and
high-energy drinks. Furthermore, urinary K
+
measurement is
correlated with surrogate outcomes, such as heart rate and BP, and is
a predictor of both all-cause and cause-specic mortality in the
general population (39).
According to current hypertension prevention guidelines, lifestyle
changes such as a healthy diet are recommended for all patients as
they can delay or complement ongoing treatment (40). Our study
provides evidence and guidance to support the adoption of behavioral
approaches in clinical settings as eective strategies to promote
healthy habits. ese approaches include improving population
education through health information, awareness, and knowledge.
erefore, the proposed interventions are crucial as they facilitate
long-term healthy behavioral changes, improve health outcomes, and
counteract the growing prevalence of unhealthy diets.
e strengths of our study include a randomized design and a
notably ample sample size. We employed an interdisciplinary
empowerment-based approach by collaborating with a
multidisciplinary team of 12 nutritionists operating within clinical
and grocery shopping settings. Furthermore, weadopted a pragmatic
approach, involving participants with hypertension and those using
antihypertensive medications. rough this deliberate inclusion of
individuals from this high-risk group, the applicability of the study
ndings to a broader population is enhanced, thereby increasing the
generalizability of our ndings. Lastly, we followed a standardized
protocol and strict quality control procedures for clinical
measurements and data collection, thus ensuring the accuracy and
consistency of our data.
On the other hand, this trial presents several limitations that
warrant acknowledgment. Firstly, dierences in group retention were
noted, with a lower attrition rate observed among participants in the
salt reduction program compared to the holistic healthy lifestyle
group. is divergence could be attributed to the comparatively
reduced contact inherent to the healthy lifestyle program, potentially
leading to a diminished level of motivation among these participants.
is variance in follow-up could potentially introduce bias favoring
the salt reduction group. However, intention-to-treat analyses
FIGURE4
Change in oce blood pressure (BP) stratified by mean quintiles of changes in weight (A,B) and adherence to Mediterranean diet (C,D), after 12-week
follow-up. Complete-case participants from salt reduction and healthy lifestyle groups were included in the analysis of systolic BP and diastolic BP.
Data are presented as mean (SEM). Significance between Q1 to Q5 quintile subgroups was assessed by one-way analysis of variance (ANOVA)
corrected with Bonferroni test for multiple comparisons. Dierences in the same quintile between salt reduction and healthy lifestyle groups were
assessed by independent t test.

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Frontiers in Public Health 11 frontiersin.org
employing multiple imputation methods, to address missing data,
yielded outcomes consistent with the complete-case analysis. Secondly,
there was an imbalance in the sex distribution, with a higher
proportion of women in the healthy lifestyle group. Nonetheless,
we addressed this disparity by incorporating sex and participant
compliance as covariates in the analysis to mitigate potential
confounding eects. irdly, the study concluded before attaining the
intended sample size of 500 participants. Although the study still
encompassed a relatively substantial sample size, the failure to reach
the target number might have impacted the statistical power to discern
dierences in outcome assessments between the groups. Fourth, due
to ethical considerations, the study lacked a no-intervention control
group, and the design did not allow double-blinding. Fih, it is worth
noting that participants who volunteer for dietary trials generally
exhibit a higher degree of motivation to adhere to a dietary program
compared to the broader population. Furthermore, most participants
were professionally active and had higher levels of education,
potentially facilitating a greater assimilation of knowledge.
Consequently, the outcomes of the programs may not beas eective
in the general population.
5. Conclusion
is study shows that empowerment-based approaches, aimed at
promoting healthy culinary habits and improved purchasing options,
eectively lower BP in the short term. However, an intervention
focused on educating participants about salt reduction was found to
be more impactful in lowering both systolic and diastolic BP,
particularly in those with high-normal or hypertensive BP. Moreover,
approaches that promote adherence to the Mediterranean diet were
associated with weight loss and a decrease in the Na
+
/K
+
ratio, resulting
in improved BP. Importantly, the decrease in BP primarily results from
an overall improvement in dietary quality, rather than being solely
attributed to changes in the Na+/K+ ratio. ese ndings highlight the
importance of targeted lifestyle interventions and the potential benets
of a Mediterranean-style diet in BP management. us, the study
results highlight the importance of promoting healthy lifestyle practices
through empowerment, aiming to prevent the onset of hypertension
and ameliorate advanced stages of elevated BP. is approach could
contribute to reducing the risk of potential complications. erefore, it
is imperative to dene new strategies that mirror a similar reduction
program promoted by registered nutritionists and dietitians, which can
provide the tools to the population for making healthier choices. is
can contribute to reducing long-term health costs and improving the
quality of life for the general population.
Data availability statement
e original contributions presented in the study are included in
the article/Supplementary material, further inquiries can bedirected
to the corresponding author.
Ethics statement
e studies involving humans were approved by Ethical
Committee of the Hospital CUF. e studies were conducted in
accordance with the local legislation and institutional requirements.
FIGURE5
Schematic representation of the clinical trial design, showing the major characteristics of the intervention groups. The outcome variables are
highlighted as well as the major findings.

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e participants provided their written informed consent to
participate in this study.
Author contributions
AM-R: Conceptualization, Data curation, Formal analysis,
Investigation, Methodology, Supervision, Validation, Visualization,
Writing – original dra. SI: Data curation, Investigation, Writing –
review & editing. IB-M: Data curation, Investigation, Writing – review
& editing. JM: Data curation, Investigation, Writing – review &
editing. CR: Data curation, Investigation, Writing – review & editing.
IC: Data curation, Investigation, Writing – review & editing. IM: Data
curation, Writing – review & editing. MIS: Data curation, Writing –
review & editing. LC: Data curation, Writing – review & editing. CBO:
Data curation, Writing – review & editing. TH: Data curation, Writing
– review & editing. PP: Data curation, Writing – review & editing.
DÉP: Data curation, Writing – review & editing. CMO: Data curation,
Writing – review & editing. JM: Data curation, Writing – review &
editing. TS: Data curation, Writing – review & editing. JA: Writing –
review & editing. JR: Writing – review & editing. DIP: Writing –
review & editing. MPS: Writing – review & editing. CM: Writing –
review & editing. AF: Writing – review & editing. JP:
Conceptualization, Formal analysis, Investigation, Supervision,
Validation, Visualization, Writing – review & editing. CC:
Conceptualization, Formal analysis, Funding acquisition,
Investigation, Supervision, Validation, Visualization, Writing – review
& editing.
Funding
e author(s) declare nancial support was received for the
research, authorship, and/or publication of this article. is work was
sponsored by CUF and Pingo Doce, as part of the Menos Sal Portugal
project, and with support from the Centro de Medicina Laboratorial
Germano de Sousa. e sponsors did not play a role in the study
design or the interpretation of the results. e study was also promoted
by the CINTESIS@RISE (UIDB/4255/2020 and UIDP/4255/2020),
NOVA Medical School of Universidade NOVA de Lisboa and
supported by national funds through FCT Fundação para a Ciência e
a Tecnologia, I.P., within the scope of the project
“RISE-LA/P/0053/2020”.
Acknowledgments
We are grateful to the facilitators, clinicians, researchers, and
administrators at Hospital CUF Descobertas, Hospital CUF Infante
Santo, and CUF Academic and Research Medical Center for their
invaluable contributions to this study. Wealso thank the team at Pingo
Doce for their collaboration in implementing the in-store component
and Centro de Medicina Laboratorial Germano de Sousa for their
support in sample processing and analysis. Finally, weextend our
appreciation to all study participants for their enthusiastic
collaboration and dedication to this research.
Conflict of interest
e authors declare that the research was conducted in the
absence of any commercial or nancial relationships that could
beconstrued as a potential conict of interest.
Publisher’s note
All claims expressed in this article are solely those of the
authors and do not necessarily represent those of their aliated
organizations, or those of the publisher, the editors and the
reviewers. Any product that may be evaluated in this article, or
claim that may be made by its manufacturer, is not guaranteed or
endorsed by the publisher.
Supplementary material
e Supplementary material for this article can befound online
at: https://www.frontiersin.org/articles/10.3389/fpubh.2023.1277355/
full#supplementary-material
References
1. Roth GA, Mensah GA, Johnson CO, Addolorato G, Ammirati E, Baddour LM, et al.
Global burden of cardiovascular diseases and risk factors, 1990-2019: update from the
GBD 2019 study. J AmColl Cardiol. (2020) 76:2982–3021. doi: 10.1016/j.jacc.2020.11.010
2. Visseren FLJ, Mach F, Smulders YM, Carballo D, Koskinas KC, Back M, et al. ESC
guidelines on cardiovascular disease prevention in clinical practice. Eur J Prev Cardiol.
(2021) 2021: 5–115. doi: 10.1093/eurjpc/zwab154
3. Eilat-Adar S, Sinai T, Yosefy C, Henkin Y. Nutritional recommendations for
cardiovascular disease prevention. Nutrients. (2013) 5:3646–83. doi: 10.3390/
nu5093646
4. Willett W, Rockstrom J, Loken B, Springmann M, Lang T, Vermeulen S, et al. Food
in the Anthropocene: the EAT-lancet commission on healthy diets from sustainable food
systems. Lancet. (2019) 393:447–92. doi: 10.1016/S0140-6736(18)31788-4
5. Davis CR, Hodgson JM, Woodman R, Bryan J, Wilson C, Murphy KJ. A
Mediterranean diet lowers blood pressure and improves endothelial function: results
from the med ley randomized intervention trial. Am J Clin Nutr. (2017) 105:1305–13.
doi: 10.3945/ajcn.116.146803
6. Sukhato K, Akksilp K, Dellow A, Vathesatogkit P, Anothaisintawee T. Ecacy of
dierent dietary patterns on lowering of blood pressure level: an umbrella review. Am J
Clin Nutr. (2020) 112:1584–98. doi: 10.1093/ajcn/nqaa252
7. Filippou CD, Tsious CP, omopoulos CG, Mihas CC, Dimitriadis KS,
Sotiropoulou LI, et al. Dietary approaches to stop hypertension (DASH) diet and blood
pressure reduction in adults with and without hypertension: a systematic review and
Meta-analysis of randomized controlled trials. Adv Nutr. (2020) 11:1150–60. doi:
10.1093/advances/nmaa041
8. Filippou CD, omopoulos CG, Kouremeti MM, Sotiropoulou LI,
Nihoyannopoulos PI, Tousoulis DM, et al. Mediterranean diet and blood pressure
reduction in adults with and without hypertension: a systematic review and meta-
analysis of randomized controlled trials. Clin Nutr. (2021) 40:3191–200. doi: 10.1016/j.
clnu.2021.01.030
9. Cicero AFG, Veronesi M, Fogacci F. Dietary intervention to improve blood pressure
control: beyond salt restriction. High Blood Press Cardiovasc Prev. (2021) 28:547–53. doi:
10.1007/s40292-021-00474-6
10. Fu J, Liu Y, Zhang L, Zhou L, Li D, Quan H, et al. Nonpharmacologic interventions
for reducing blood pressure in adults with prehypertension to established hypertension.
J AmHeart Assoc. (2020) 9:e016804. doi: 10.1161/JAHA.120.016804
11. Schwingshackl L, Chaimani A, Schwedhelm C, Toledo E, Punsch M, Homann G,
et al. Comparative eects of dierent dietary approaches on blood pressure in
hypertensive and pre-hypertensive patients: a systematic review and network meta-
analysis. Crit Rev Food Sci Nutr. (2019) 59:2674–87. doi: 10.1080/10408398.2018.1463967

Moreira-Rosário et al. 10.3389/fpubh.2023.1277355
Frontiers in Public Health 13 frontiersin.org
12. Rosato V, Temple NJ, La Vecchia C, Castellan G, Tavani A, Guercio V.
Mediterranean diet and cardiovascular disease: a systematic review and meta-analysis
of observational studies. Eur J Nutr. (2019) 58:173–91. doi: 10.1007/s00394-017-1582-0
13. Bonaccio M, Iacoviello L, Donati MB, de Gaetano G. e tenth anniversary as a
UNESCO world cultural heritage: an unmissable opportunity to get back to the cultural
roots of the Mediterranean diet. Eur J Clin Nutr. (2022) 76:179–83. doi: 10.1038/
s41430-021-00924-3
14. Critselis E, Kontogianni MD, Georgousopoulou E, Chrysohoou C, Tousoulis D,
Pitsavos C, et al. Comparison of the Mediterranean diet and the dietary approach stop
hypertension in reducing the risk of 10-year fatal and non-fatal CVD events in healthy
adults: the ATTICA study (2002-2012). Public Health Nutr. (2021) 24:2746–57. doi:
10.1017/S136898002000230X
15. Brandstetter S, Ruter J, Curbach J, Loss J. A systematic review on empowerment
for healthy nutrition in health promotion. Public Health Nutr. (2015) 18:3146–54. doi:
10.1017/S1368980015000270
16. Lindacher V, Curbach J, Warrelmann B, Brandstetter S, Loss J. Evaluation of
empowerment in health promotion interventions: a systematic review. Eval Health Prof.
(2018) 41:351–92. doi: 10.1177/0163278716688065
17. Wang ML, Otis M, Rosal MC, Griecci CF, Lemon SC. Reducing sugary drink
intake through youth empowerment: results from a pilot-site randomized study. Int J
Behav Nutr Phys Act. (2019) 16:58. doi: 10.1186/s12966-019-0819-0
18. Jurkowski JM, Lawson HA, Green Mills LL, Wilner PG 3rd, Davison KK. e
empowerment of low-income parents engaged in a childhood obesity intervention. Fam
Community Health. (2014) 37:104–18. doi: 10.1097/FCH.0000000000000024
19. Cyril S, Smith BJ, Renzaho AM. Systematic review of empowerment measures
in health promotion. Health Promot Int. (2016) 31:809–26. doi: 10.1093/heapro/
dav059
20. WHO. Ottawa charter for health promotion. Can J Public Health. (1986)
77:425–30.
21. Tremblay MC, Richard L. Complexity: a potential paradigm for a health promotion
discipline. Health Promot Int. (2014) 29:378–88. doi: 10.1093/heapro/dar054
22. Polonia J, Martins L, Pinto F, Nazare J. Prevalence, awareness, treatment and
control of hypertension and salt intake in Portugal: changes over a decade. PHYSA study
J Hypertens. (2014) 32:1211–21. doi: 10.1097/HJH.0000000000000162
23. Polonia J, Lobo MF, Martins L, Pinto F, Nazare J. Estimation of populational 24-h
urinary sodium and potassium excretion from spot urine samples: evaluation of four
formulas in a large national representative population. J Hypertens. (2017) 35:477–86.
doi: 10.1097/HJH.0000000000001180
24. Stergiou GS, Palatini P, Parati G, O'Brien E, Januszewicz A, Lurbe E, et al. 2021 European
Society of Hypertension practice guidelines for oce and out-of-oce blood pressure
measurement. J Hypertens. (2021) 39:1293–302. doi: 10.1097/HJH.0000000000002843
25. Coleman A, Steel S, Freeman P, de Gree A, Shennan A. Validation of the Omron
M7 (HEM-780-E) oscillometric blood pressure monitoring device according to the
British hypertension society protocol. Blood Press Monit. (2008) 13:49–54. doi: 10.1097/
MBP.0b013e3282cb57b6
26. Saúde D-G. Avaliação Antropométrica no Adulto. Lisboa, Portugal: Direção-Geral
da Saúde (2013).
27. Schroder H, Fito M, Estruch R, Martinez-Gonzalez MA, Corella D, Salas-Salvado
J, et al. A short screener is valid for assessing Mediterranean diet adherence among older
Spanish men and women. J Nutr. (2011) 141:1140–5. doi: 10.3945/jn.110.135566
28. Muscogiuri G, Barrea L, Laudisio D, Di Somma C, Pugliese G, Salzano C, et al.
Somatotropic Axis and obesity: is there any role for the Mediterranean diet? Nutrients.
(2019) 11:2228. doi: 10.3390/nu11092228
29. Barrea L, Muscogiuri G, Laudisio D, Pugliese G, de Alteriis G, Colao A, et al.
Inuence of the Mediterranean diet on 25- Hydroxyvitamin D levels in adults. Nutrients.
(2020) 12:1439. doi: 10.3390/nu12051439
30. Savanelli MC, Barrea L, Macchia PE, Savastano S, Falco A, Renzullo A, et al.
Preliminary results demonstrating the impact of Mediterranean diet on bone health. J
Transl Med. (2017) 15:81. doi: 10.1186/s12967-017-1184-x
31. Graham JW. Missing data analysis and design. Berlin: Springer (2012).
32. Lee KW, Loh HC, Ching SM, Devaraj NK, Hoo FK. Eects of vegetarian diets on
blood pressure lowering: a systematic review with Meta-analysis and trial sequential
analysis. Nutrients. (2020) 12:1604. doi: 10.3390/nu12061604
33. Gregorio BM, De Souza DB, de Morais Nascimento FA, Pereira LM, Fernandes-
Santos C. e potential role of antioxidants in metabolic syndrome. Curr Pharm Des.
(2016) 22:859–69. doi: 10.2174/1381612822666151209152352
34. Abeywardena MY, Head RJ. Longchain n-3 polyunsaturated fatty acids and blood
vessel function. Cardiovasc Res. (2001) 52:361–71. doi: 10.1016/S0008-6363(01)00406-0
35. Djousse L, Rudich T, Gaziano JM. Nut consumption and risk of hypertension in
US male physicians. Clin Nutr. (2009) 28:10–4. doi: 10.1016/j.clnu.2008.08.005
36. Medina-Remon A, Estruch R, Tresserra-Rimbau A, Vallverdu-Queralt A,
Lamuela-Raventos RM. e eect of polyphenol consumption on blood pressure. Mini
Rev Med Chem. (2013) 13:1137–49. doi: 10.2174/1389557511313080002
37. Mancia G, Fagard R, Narkiewicz K, Redon J, Zanchetti A, Bohm M, et al. 2013
ESH/ESC guidelines for the management of arterial hypertension: the task force for the
management of arterial hypertension of the European Society of Hypertension (ESH)
and of the European Society of Cardiology (ESC). J Hypertens. (2013) 31:1281–357. doi:
10.1097/01.hjh.0000431740.32696.cc
38. Neter JE, Stam BE, Kok FJ, Grobbee DE, Geleijnse JM. Inuence of weight
reduction on blood pressure: a meta-analysis of randomized controlled trials.
Hypertension. (2003) 42:878–84. doi: 10.1161/01.HYP.0000094221.86888.AE
39. Mente A, Irvine EJ, Honey RJ, Logan AG. Urinary potassium is a clinically useful
test to detect a poor quality diet. J Nutr. (2009) 139:743–9. doi: 10.3945/jn.108.098319
40. Mancia Chairperson G, Kreutz Co-Chair R, Brunstrom M, Burnier M, Grassi G,
Januszewicz A, et al. 2023 ESH guidelines for the management of arterial hypertension
the task force for the management of arterial hypertension of the European Society of
Hypertension Endorsed by the European renal association (ERA) and the International
Society of Hypertension (ISH). J Hypertens. (2023) 41:1874–2071. doi: 10.1097/
HJH.0000000000003480