Salt Substitutes in Low-Income Settings: Blood Pressure Benefits, Cardiovascular Outcomes, and Safety Considerations: A Narrative Review

Abstract

Background: Hypertension remains a leading cause of cardiovascular morbidity and mortality, disproportionately affecting low- and middle-income countries (LMICs), where healthcare access and awareness are limited. Excessive sodium intake, often from discretionary salt used in cooking, contributes significantly to this burden. Salt substitutes, typically formulated by partially replacing sodium chloride with potassium chloride or other minerals, offer a cost-effective dietary intervention to lower blood pressure (BP) and reduce cardiovascular risk, particularly in resource-constrained settings. Objective: This review examines the efficacy of low-sodium salt substitutes (LSSS) in reducing blood pressure (BP) and its effects on cardiovascular (CV) outcomes, safety concerns, and challenges to their implementation in LMICs. Methods: We conducted a comprehensive narrative review of studies published between 1994 and 2024 using PubMed, Embase, and Scopus databases. Eligible studies included randomized controlled trials, systematic reviews, observational studies, and implementation research that evaluated the effects of LSSS on BP, CV outcomes, safety, and feasibility in LMIC contexts. Thematic synthesis was used to summarize the findings. Key Findings: Salt substitutes consistently lowered systolic and diastolic BP across diverse populations, with mean reductions ranging from 3 to 5 mmHg. Trials have also demonstrated reductions in stroke incidence, CV events, and all-cause mortality. However, the benefits were mostly derived from studies conducted in China and other upper-middle-income settings. Safety concerns (particularly hyperkalemia in individuals with chronic kidney disease or RAAS inhibitors) warrant targeted risk screening and public education. Implementation barriers in LMICs include cost, limited availability, poor awareness, and a lack of regulatory oversight. Conclusions: Salt substitutes present a promising, scalable strategy to reduce BP and CV disease burden in LMICs. However, their adoption must be context-specific, culturally sensitive, and supported by government subsidies, regulatory frameworks, and educational campaigns. Future trials should evaluate the long-term safety and cost-effectiveness in underrepresented LMIC populations to guide equitable public health interventions.

1. Introduction

According to the World Health Organization (WHO), high blood pressure, or hypertension, is the term used if a patient’s systolic blood pressure (SBP) is more than or equal to 140 mmHg and/or diastolic blood pressure is more than or equal to 90 mmHg [1]. Worldwide, approximately 10.8 million lives are lost, which is avoidable. Hypertension also adds to approximately 235 million years of life lost or disability-adjusted life years per year [2].

Hypertension (HTN) is the most common cause of mortality worldwide. Nearly 1.25 billion adults of the age group 30–79 years had hypertension [3]. Around 2/3 rds of all hypertensive patients are located in LMICs (low- or middle-income countries) [1]. WHO statistics show that Africans, being low-income countries, have a 27% (highest) prevalence of hypertension compared to 18% (lowest) in the USA [4]. According to the World Health Organization, approximately 80% of hypertensive people are inadequately treated, and there is a projection that from 2030 to 2050, approximately 76 million deaths could be prevented with effective management [2].

Although the prevalence of hypertension is almost similar in both high-income and low-income countries, high-income countries account for 58% of treated patients, compared to 26% in low-income countries, which is less than half. Hypertension contributes to approximately 51% of global mortality due to coronary heart disease and 62% of global deaths due to stroke [5].

Hypertension is usually associated with various modifiable and nonmodifiable risk factors. Modifiable factors include increased salt consumption, reduced amounts of fruits and vegetables, high-fat diets (saturated and trans fats), lack of physical activity, increased body mass index (BMI), smoking, and alcohol consumption. Non-modifiable factors include positive family history, elderly age (age > 65 years), and comorbidities, such as DM/CKD [4].

Among these risk factors, high-sodium and low-potassium diets are known to cause increased blood pressure, which can be easily modified [6]. To reduce blood pressure, the WHO recommends that sodium intake should be less than 2 g/day and potassium intake should be 70–80 mmol per day [7]. According to the Dietary Guidelines for Americans, people consume a high amount of sodium, which should be less than 2300 mg/day for the general population and less than or nearly 1500 mg per day for people with hypertension and an increased risk of CVD. It is also advised that Americans should increase the potassium content in their diet, which also has beneficial effects in reducing high blood pressure [8,9,10].

As the majority of hypertensive patients live in LMICs, a cost-effective and affordable strategy that can be implemented at the national level is required. This is achievable with dietary modifications, including low-sodium salt substitutes enriched with potassium, which showed significant benefits in reducing BP and, hence, associated cardiovascular diseases [3,6].

Salt alternatives have shown success in lowering the rates of stroke, CVD, hypertension, and related fatalities [11]. The WHO’s strategy for reducing sodium intake using salt alternatives is in line with global health policies and supports the Sustainable Development Goals. These strategies aim to reduce the death rate from non-communicable diseases by one-third by 2030 by incorporating salt substitutes into national dietary guidelines, food security programs, and supply chains [12]. According to WHO guidelines, less than 2000 mg of sodium per day should be consumed, which is equivalent to less than 5 g of salt per day. It has been reported that salt utilization is above the recommended level in most countries [7].

It has been observed that cooking habits, salt addition while cooking, contribute to the high salt intake in South Asian countries and LMICs. In addition, a shift towards processed foods with high sodium content has been observed, leading to increased chronic diseases, including hypertension, among communities of South Asia [5].

In addition, strong evidence of the effectiveness of strategy implementation with a nationwide approach has been observed in the UK, Finland, and Japan as compared to the USA, which is dietary modification at the individual level. Positive outcomes of public- and national-level interventions have been observed compared to implementation at the individual level. Studies conducted in the UK, Finland, and Japan showed that interventions such as reduced amounts of sodium in processed food led to better outcomes in reducing CVDs than in the USA, where increased awareness about sodium and potassium consumption encouraged individuals to make changes in individual diets, but without many positive outcomes [13].

In 2017, around 3.2 million deaths were reported due to increased consumption of sodium (modifiable factor) [3]. Salt supplements have been proven to be a cost-effective strategy to achieve low sodium and high potassium intakes. Sodium chloride [100% NaCl salt] used in household kitchens, a part of it is replaced by potassium chloride or magnesium sulfate, a substitute that reduces sodium level and increases potassium level in diet [14]. This has a positive effect on blood pressure reduction.

Increased potassium and reduced sodium in the diet are beneficial for prehypertensive and hypertensive patients or people at high risk of CVD, but the effect on the normotensive population or children is yet to be studied; therefore, the implementation of the strategy cannot be generalized for the whole population. In addition, few studies have been conducted in low- and middle-income countries (LIMCs) such as Peru, China, and India; the majority of the database contains studies from high-income countries such as the USA and the UK [15].

Figure 1 illustrates the global evidence and impact pathway of low-sodium salt substitutes (LSSS).

This narrative study focuses on LMICs, as most of the hypertensive population is in low- or middle-income countries, which have limited healthcare resources. Along with that, there are limited studies conducted in these countries. Before generalization of an approach, it is necessary that sufficient studies are conducted in LMICs in a wider age group, including pregnant women and children, so that better results can be anticipated in a nationwide approach. In addition, studies need to be conducted on the safety of low-sodium salt substitutes, which have high amounts of potassium, in the normal population as well as in people with other comorbidities such as CKD.

2. Materials and Methods

We conducted a narrative literature review to synthesize evidence on low-sodium salt substitutes (LSSS) in human populations. A comprehensive search of PubMed, Embase, and Scopus (1994–2025) was performed for English-language studies on salt substitutes, blood pressure, cardiovascular outcomes, safety, and implementation. Inclusion criteria were broad and encompassed by randomized controlled trials (RCTs), systematic reviews and meta-analyses, large implementation trials or programs, and relevant observational studies in human populations (particularly focusing on low- and middle-income settings). We emphasized studies published in the past ~30 years to capture contemporary salt reduction initiatives and products. After screening titles and abstracts, eligible full texts were reviewed. Findings were organized via thematic synthesis into key domains: blood pressure effects, cardiovascular outcome trials, safety considerations, and implementation strategies. This narrative approach (as opposed to a formal systematic review) allowed inclusion of diverse study designs and gray literature (WHO reports) to contextualize LSSS use. No formal meta-analysis was conducted, but we triangulated evidence across sources to draw conclusions.

3. Review

3.1. Blood Pressure–Lowering Effect of Salt Substitutes

Substitution of regular salt with LSSS has shown consistent blood pressure–lowering effects across various populations. A Cochrane meta-analysis (2021) encompassing 26 clinical trials with over 34,000 adults concluded that replacing normal salt with LSSS reduced systolic blood pressure (SBP) by 4.76 mmHg and diastolic blood pressure (DBP) by 2.43 mmHg. Although the reduction may not be clinically significant at the individual level, it has substantial public health implications [15].

Similarly, a systematic review published in 2022 (23 RCTs; 32,073 participants) reported a mean SBP reduction of 4.8 mmHg and DBP reduction of 1.48 mmHg. The study also demonstrated a 12% decrease in all-cause mortality and 9.6% reduction in cardiovascular mortality with LSSS use. Greater BP reductions were observed in older adults, although precise subgroup values were not provided [3]. A randomized controlled trial among normotensive elderly individuals in China confirmed that LSSS use was associated with a lower incidence of hypertension, suggesting that LSSS is safe and avoids the risk of hypotension in this age group [16].

Table 1. Summary of studies evaluating the effects of salt substitutes on blood pressure (BP).

Study	Country	Population	Duration	Salt Substitute Composition	SBP ↓ (mmHg)	DBP ↓ (mmHg)	Limitation
Neal et al. (2021) [11]	China	600 villages (Rural China)	Variable	75% NaCl, 25% KCl	3.34	0.67	Only included people ≥ 60 years
Geleijnse et al. (1994) [17]	Netherlands	100 men and women between 55 and 75 years of age	24 weeks	Sodium: Potassium: Magnesium: 8:6:1	7.6	3.3	Did not Include people below <50 who also took great hit by prevalence of Hypertension
He et al. (2002) [18]	Global	Mixed RCTs	Variable	LSSS	7.11	3.88	Not all studies are blinded.
Greer et al. (2020) [19]	Global	RCTs	Variable	K-enriched LSSS	5.58	2.88	Limited evidence on effect of potassium rich salt substitute on serum potassium levels in CKD
Yu et al. (2021) [20]	India	502 (7 villages in rural India)	3 months	70% NaCl 30% KCl	4.6	1.1	Follow up Duration is short people with CKD are not included.
Peng et al. (2014) [21]	Mixed Territories	Mixed RCTs (1974 participants)	Variable	Variable	4.9	1.5	None of the studies included people with CKD, Sample sizes are less for normotensive group.
Yuan et al. (2023) [22]	China	1612 participants (elderly care facilities)	6 months	62.5% NaCl 25% KCl	7.1	1.9	-
Bernabe Otriz et al. (2020) [23]	Peru	2376	Variable	75% NaCl, 25% KCl	1.29	0.76	Not Included people with CKD and taking Digoxin.

Table footnote: ↓ = Decrease.

presents studies conducted across various countries and populations, detailing the type and composition of salt substitutes used, study duration, and resulting systolic (SBP) and diastolic blood pressure (DBP) reductions.

Population-Specific Findings

In hypertensive Chinese populations, LSSS reduced SBP by 5.7 mmHg and DBP by 2.4 mmHg. Normotensive individuals also showed BP reduction, although this was not statistically significant [21]. A stepped-wedge randomized controlled trial conducted in Peru evaluated the effects of a low-sodium salt substitute containing 75% NaCl and 25% potassium chloride. This intervention led to a reduction in blood pressure across the various population subgroups. Among individuals with hypertension, systolic and diastolic blood pressure decreased by 1.92 mmHg and 1.18 mmHg, respectively. In normotensive participants, the reductions were slightly lower, with systolic pressure decreasing by 1.15 mmHg and diastolic by 0.63 mmHg. Age-stratified analysis revealed the greatest blood pressure reductions in participants aged 60 years and above, with systolic and diastolic pressures declining by 2.17 mmHg and 1.18 mmHg, respectively. Participants aged 40 to 59 years experienced modest decreases (SBP 1.17 mmHg, DBP 1.01 mmHg), while those under 40 showed a minimal and statistically non-significant reduction (SBP 0.94 mmHg, DBP 0.27 mmHg) [23].

A 2013 Chinese RCT showed 2 mmHg reductions in both SBP and DBP in normotensives and 4 mmHg SBP reduction in hypertensives using 65% NaCl, 25% KCl, and 10% MgSO₄ [3]. Another study reported a 5.32 mmHg SBP reduction in hypertensives compared to just 0.09 mmHg in normotensives using the same salt composition [24].

3.2. Cardiovascular Outcomes

Evidence strongly supports the use of salt substitutes to reducing blood pressure and improve cardiovascular outcomes. A landmark randomized controlled trial in China, the Salt Substitute and Stroke Study (SSaSS), followed 20,995 older adults over 4.74 years. Participants who used a salt substitute containing 75% sodium chloride and 25% potassium chloride experienced significantly lower rates of stroke (29.14 vs. 33.65 events per 1000 person-years), major cardiovascular events (49.09 vs. 56.29), and all-cause mortality (39.28 vs. 44.61) compared to those using regular salt. These results highlight the public health potential of salt substitutions in high-risk populations [5]. Another economic analysis revealed that LSSS use led to lower inpatient and outpatient healthcare costs, highlighting the potential cost-saving effects of such public health interventions [25]. In India, a 3-month RCT with 476 hypertensive patients showed that 70% NaCl and 30% KCl reduced SBP by 4.58 mmHg and DBP by 1.14 mmHg [20].

Limitations in LMICs

Although the benefits of LSSS are well supported in high- and upper-middle-income countries, especially China, evidence from LMICs remains limited. This is a concern, as LMICs face a high burden of hypertension along with resource-constrained health systems. Key challenges include low awareness and limited screening for hypertension, poor adherence to treatment owing to silent nature, inadequate rural healthcare infrastructure, and the cost and availability of LSSS. Addressing these issues is essential for extending the benefits of salt substitution to LMICs. Thus, comparative effectiveness trials between LSSS and antihypertensive medications are urgently needed to inform national health policy.

3.3. Major Cardiovascular Outcome Trials on Salt Substitutes

Primary outcome trials have consistently shown that replacing regular salt with a potassium-enriched substitute yields clinically meaningful cardiovascular benefits. Notably, the SSaSS in China demonstrated significant reductions in stroke and major CV events over 5 years [26]. The Taiwan trial in an elderly cohort likewise found substantially lower CVD mortality over ~2.5 years with a KCl-enriched salt [27]. These outcome data reinforce earlier blood pressure trials by confirming that blood pressure lowering from salt substitutes translates into fewer strokes, heart attacks, and CV deaths in the long run.

Several large trials have evaluated whether replacing regular salt with potassium-enriched salt substitutes can reduce “hard” cardiovascular outcomes beyond blood pressure.

Table 2. Major Trials Assessing Cardiovascular Outcomes with Salt Substitute Use.

Study (Year)	Country/Setting	Population	Intervention	Duration	Main CV Outcome	Key Limitations
SSaSS (2021) [26]	China, rural (600 villages)	~21,000 adults ≥ 60 year (72% with stroke/HTN)	75% NaCl/25% KCl	5 y	↓ Stroke (−14%), ↓ major CV events (−13%), ↓ mortality (−12%)	Cluster design, open-label, rural only, excluded CKD
Chang et al. (2006) [27]	Taiwan (veterans’ homes)	1981 older men (~75 year)	50% NaCl/50% KCl	2.6 y	↓ CVD mortality (41% reduction)	Older men only, single-center, not blinded, few events
DECIDE-Salt (2024) [28]	China (48 eldercare facilities)	~1600 elderly (many hypertensive)	70% NaCl/30% KCl	2 y	↓ BP, fewer CV events (trend), no mortality effect	Institutionalized elderly, short follow-up, low event rates, hyperkalemia monitoring

Table footnote: ↓ = Decrease.

summarizes the major trials reporting cardiovascular endpoints:

3.4. Safety Concerns: Focus on Hyperkalemia

Hyperkalemia is defined as Serum or Plasma potassium levels higher than the upper limit of the normal range, i.e., 3.5–5 mEq/L. Serum potassium levels of 5.0 mEq/L to 5.5 mEq/L are usually asymptomatic. Symptoms arise when potassium levels cross 6.5 mEq/L to 7 mEq/L. The symptoms include cardiac arrhythmia, muscle weakness, or paralysis. There are three methods to achieve high potassium levels: 1. High Intake 2. Transcellular potassium shifted by 3. Decreased excretion [29].

Increased potassium intake from potassium-rich foods such as kiwi and dried fruits is not a common cause of hyperkalemia because of normal functioning kidneys, but it becomes a problem when a person is suffering from kidney disease. Transcellular shifts in potassium during acidosis, as in DKA and muscle damage, can also contribute to hyperkalemia. Decreased excretion of potassium is observed in conditions such as chronic kidney disease, where patients are able to excrete potassium and are unable to maintain balance [29,30].

Potassium is usually an intracellular cation. The sodium-potassium pump, which is located on the cell membrane, is responsible for maintaining the potassium inside the cells by pumping sodium and importing potassium in a 3:2 ratio. The most common complication of hyperkalemia is conduction abnormalities in the heart, leading to dysrhythmias and death [31].

3.4.1. Who Is at Risk: CKD, HF, RAAS Inhibitors

When beginning salt substitution, we should take care of people who are at risk of chronic kidney disease and are not able to maintain potassium homeostasis, so beginning salt substitution in these people can lead to dangerous hyperkalemia. People who are on ACE Inhibitors, AT II receptor blockers, and potassium-sparing diuretics should also be considered before starting salt substitution because it predisposes them to hyperkalemia. Heart failure also decreases the effective blood volume in the kidneys, predisposing patients to salt substitution. The above-mentioned people are at high risk, so we should be hypervigilant before commencing salt substitution in these patients [32].

3.4.2. Data from Trials (Incidence and Severity of Adverse Effects)

Data from various trials suggest that there are concerns about the potential side effects of LSSS, especially hyperkalemia, particularly in people who are suffering from CKD or taking any medications that impair potassium excretion, such as ACE Inhibitors and ARBs.

Many studies have excluded patients who were at risk of hyperkalemia, so there is little data on the dose–response relationship between LSSS and hyperkalemia. There are concerns that it increases the risk of hyperkalemia and sudden cardiac arrest in people with limited kidney function and impaired potassium excretion [33]. The risk of adverse side effects, such as arrhythmia, arises when potassium levels exceed 6 mmol/L. The rate of increase is also important, because acute changes cause more pronounced symptoms. The risk of hyperkalemia also increases in heart failure, DM, older adults, and adrenal insufficiency [19].

3.4.3. Importance of Population Screening and Education

There is little to no research on the benefits and risks of LSSS in people with CKD or in those taking medications such as potassium-sparing diuretics that interfere with the RAAS axis. Labeling LSSS with the percentage of potassium and health warning on the risk of hyperkalemia should be mentioned. One survey conducted in India among doctors showed that participants did not know about the contraindications of LSSS in patients with CKD who were using potassium-sparing diuretics. Educational campaigns among consumers on how to read labeling and regulations on labeling are necessary to make people aware of potential side effects and to increase their ability to make informed decisions [33].

3.5. Safety of Potassium-Substituted Salts (Hyperkalemia and At-Risk Groups)

The primary safety concern with potassium-based salt substitutes is the risk of hyperkalemia (elevated blood potassium), which in severe cases can precipitate cardiac arrhythmias. This is particularly a worry for individuals with reduced kidney function or others who have impaired potassium excretion.

Reassuringly, major trials have generally found no significant increase in serious hyperkalemic events with potassium-enriched salts when high-risk individuals are excluded. In the 20,000-person SSaSS trial, the rate of serious adverse events attributed to hyperkalemia was not higher with the salt substitute than with regular salt [6,11]. Notably, SSaSS did not perform routine blood tests during follow-up (a pragmatic design), so asymptomatic biochemical hyperkalemia could not be measured; however, there was no excess of sudden cardiac deaths in the salt substitute group [11], suggesting no occult hyperkalemia-related arrhythmia signal. In fact, only 2 participants in SSaSS were identified as having definite or probable hyperkalemia over 5 years, and this was the same number in the control group [11,22]. Another 313 participants had “possible” hyperkalemia events (symptoms or incidental labs), but again with no difference between groups [22].

Smaller RCTs echo this finding. The DECIDE-Salt trial in older adults proactively measured serum potassium: the salt-substitute group did show a slight increase in mean potassium level and more cases of biochemical hyperkalemia, but no participants suffered adverse clinical events as a result [22]. In other words, some lab values exceeded the normal range, but these were generally transient and did not translate into illness. A recent meta-analysis of salt substitute trials likewise concluded that there was no significant risk of clinical hyperkalemia attributable to the intervention [6,22,33].

SSaSS excluded anyone who reported a history of severe kidney disease or use of potassium-sparing drugs, although kidney function was not directly measured [34,35]. This means the trial data apply to the general population without known severe CKD. In DECIDE-Salt (which did not exclude based on kidney function), a few more high-K readings were seen, affirming that risk is tangible if salt substitutes are used without any screening at all [22]. Still, even in that scenario, no adverse outcomes occurred—likely because the elevations were mild and intermittent [22,33].

Subpopulations at risk: People with advanced CKD (generally stage 4–5, or eGFR < 30 mL/min) are the highest-risk group for hyperkalemia from increased potassium intake, and most guidelines advise against KCl-based salt substitutes in these patients [36]. UK’s NICE guidelines explicitly warn that potassium-containing salts should be avoided by individuals with kidney disease, and also by certain other groups (older people, those with diabetes, or those on ACE-inhibitor/ARB medications) [6,36]. We believe such broad restrictions may be overly cautious in some cases—for example, many older people or diabetics have normal kidney function and would benefit greatly from salt substitution. Blanket contraindications for all diabetics or all seniors are not evidence-based [6,11].

Improving access to basic lab monitoring in primary care would further mitigate risk. Even infrequent spot-checks of serum potassium among high-risk subgroups (for instance, yearly screening in hypertensive or diabetic patients) could catch asymptomatic hyperkalemia. Unfortunately, in many low-resource areas this is aspirational. Another approach is training healthcare workers to recognize signs of hyperkalemia (such as muscle weakness or abnormal heart rhythms on examination) and to have protocols for emergency care. Importantly, the dose of potassium from salt substitutes is still fairly modest—using a 25% KCl salt in typical amounts raises potassium intake by only a couple of grams per day, which is usually well-tolerated if renal function is normal [11,22]. For perspective, one banana contains ~0.4 g of potassium; the salt substitute provides perhaps the equivalent of 5–6 extra bananas’ worth spread over an entire day’s meals. Individuals with normal renal function can excrete this extra load readily [6,36].

3.6. Implementation in Low-Income Settings

A study from Bangladesh suggested that there is no requirement for special technology or advanced medical supervision for LSSS delivery and usage by people [37]. The LSSS policy was estimated to be a cost-saving intervention at 10 years, 20 years, and over the lifespan of the adult cohort owing to the substantial net healthcare cost savings (US $65 per capita) outweighing implementation costs (∼US $16 per capita) [38].

The median price of low-sodium salts in upper-middle-income and lower-middle-income countries was US $2.70/kg and US $2.90/kg, respectively. The price of low-sodium salt is between 1.1 and 14.6 times that of normal regular salt [33]. Salt substitution was truly cost-saving because the additional costs associated with salt substitution were offset by savings in healthcare costs, primarily through a reduction in the number of nonfatal events requiring hospitalization. Salt substitution also reduces costs during outpatient visits and outpatient medications. A study in China showed that the salt substitution group’s risk was reduced by 14%, and the salt substitute group had, on an average, 0.054 QALYs per person better than normal salt. This was followed for over 4.7 years [25].

A study in China predicted that the implementation of LSSS could prevent nearly 461,000 cardiovascular deaths and 743,000 non-fatal cardiovascular events each year [25]. While low-sodium salts are widely available in developed countries, there is a need for their availability in low- and middle-income countries. One study found that out of 87 available low-sodium salts, only 6 of them are found in low- and middle-income countries [33].

Population-level salt reduction has been pursued through various strategies worldwide.

Table 3. Salt Reduction Strategies and Outcomes in Selected Countries.

Country	Strategy & Level	Key Outcomes
United Kingdom	Voluntary reformulation + public campaigns; government-led until ~2010, then industry-led	Salt intake dropped from ~9.4 g/day (2000) to ~7.6 g/day (2014); BP declined ~2–3 mmHg. Stroke and IHD mortality fell by ~30–40%, though progress stalled post-2014 [39,40].
Finland	Legislation, labeling, reformulation, K-enriched salt (Pansalt)	Sodium intake ↓ ~40%; BP dropped >10 mmHg; stroke & IHD mortality ↓ ~75–80% [41,42].
Japan	Government-led public health campaigns since the 1960s, especially in high-salt regions	Salt intake fell significantly (18 g/day → ~14 g/day); stroke mortality dropped ~80% [41].
China	Mixed strategies: public awareness, community tools (e.g., salt spoons), pilot salt substitute initiatives	National intake remains high (~10.9 g/day, 2019); the SSaSS trial showed ~3 mmHg BP reduction and 14% lower stroke risk [11,41].
India	Public advisories and pilot low-sodium iodized salt programs at state/local levels	Salt intake remains ~11 g/day; pilot trials show promising acceptance but limited large-scale impact [43].
Peru	National front-of-pack labeling + community “Salt Liz” salt-substitute campaign	SBP reduced by ~1.3 mmHg; hypertension risk halved (51% lower incidence); high adoption rates observed [23].

Table footnote: ↓ = Decrease, → = Indicates changes of doses with respect to days.

contrasts approaches and outcomes in selected countries/regions—the United Kingdom, Finland, Japan, China, India, and Peru—which illustrate a spectrum from high-income to lower-income settings and different strategy types:

Different countries have taken different paths to reducing salt intake. The UK and Finland demonstrate that both voluntary and legislative approaches, if well-implemented, can yield substantial reductions in population sodium and cardiovascular improvements. Japan’s historical success underscores the impact of dietary education in a high-intake culture. In large emerging economies like China and India, the push for salt substitutes is more recent—early results (in trials) are promising, but nationwide impact is not yet realized. Lower-income settings (India, Peru) show that household-level substitution strategies can work, but cost, supply, and awareness barriers must be overcome. Overall, a combination of policy measures (food industry reformulation, labeling) and grassroots initiatives (education, substitution programs) seems most effective in achieving sustained salt reduction [42,44].

3.6.1. Acceptability (Taste, Habits, Marketing)

There has been some evidence that increasing potassium in LSSS by more than 30% leads to unpleasant off-taste. Several other studies, including the study conducted in Peru, concluded that capping KCl at 25% does not result in any taste difference between normal salt and LSSS. However, the composition of the LSST should be carefully curated according to local taste needs. Taste-improving agents can also be included in LSSS to overcome the sensory input of LSSS by adding umami ingredients or by taste masking [45].

3.6.2. Lack of Regulatory Oversight and Safety Monitoring

There should be a regulatory body that oversees the safety of LSSS, but it should not be a roadblock for its implementation in a larger population group because of its potential use in reducing CVD deaths and decreasing healthcare costs. As with vaccines, trans fat bans, and iodization, surveillance must occur in parallel with implementation, not before it.

Labeling should be performed on all the substitutes clearly and concisely rather than vaguely by providing the benefits and harms of LSSS. Benefits include decreasing blood pressure and reducing the risk of stroke, while harm includes an increased incidence of hyperkalemia in patients who are renally impaired and have serious kidney disease. Regulation should be made and strict vigilance should be implemented [46].

3.6.3. Case Studies: China, Sri Lanka, and Lessons Learned

The success of LSSS depends mainly on systemic implementation in a graded fashion by the government. The government must integrate salt substitution into national health schemes and create laws on industry regulations to achieve higher levels of success. The salt substitution scheme makes changes to the environment of the people rather than depending on individuals to make changes in their behavior, so there is a high scope for success with this program [47,48].

In contrast to the UK, where salt substitution was made at the industry level because the majority of salt intake comes from processed food, salt substitution in LMICs should be made at the household level, where the majority of their intake is from cooking [7].

3.6.4. Equity and Feasibility Concerns

Most low-income and middle-income countries suffer from a large burden of cardiovascular deaths. This is mainly because of unhealthy diets, which mostly consist of high sodium levels. The most effective way to address the growing CVD burden is sodium restriction with low-sodium salts. This is the most effective method because the primary source of sodium mainly comes from the salt used in cooking, which is discretionary and results in no behavioral change, but the availability of LSSS in low- and middle-income countries is extremely low [7,49,50]. The cost of LSSS is higher than that of normal salt, and in countries such as India, the availability of potassium, which is a top ingredient in LSSS, is also low, increasing the cost. The cost of food is an important factor that influences consumers to make decisions on the salt they will use while cooking [38,51].

Reducing the price gap between LSSS and normal salt should be taken up by the government by providing subsidies; this increases the affordability for common people who face a high risk of CVD burden. Accessibility of LSSS within a nominal range makes people go for it, and in this way, we can make salt substitution equitable and feasible across all population groups in low- and middle-income countries [51].

3.7. Implementation Strategies and Partnerships in Low-Income Settings

Implementing salt substitute interventions in low-income settings requires creative strategies and multi-stakeholder partnerships. We have expanded the “Implementation” section to illustrate how collaborations with non-governmental organizations (NGOs), community groups, and food manufacturers can facilitate successful rollout of LSSS programs:

Community engagement and NGO partnerships: One of the clearest lessons is that working with local communities—and the NGOs or civic organizations embedded in them—greatly improves uptake of salt substitutes. In the Peru Salt-Liz project, researchers partnered with local community health workers and volunteers branded as “Amigas de Liz” (Friends of Liz) to promote the low-sodium salt. These volunteers visited households, organized village workshops, and even hosted entertainment events (raffles, bingo nights, cooking demonstrations) to spark interest [52]. Such community-led social marketing created grassroots buy-in. An NGO played a role in subsidizing and distributing the salt substitute, ensuring it was provided free of charge to families during the trial. The result was near-universal adoption in the intervention villages—a level of behavior change seldom seen with purely top-down approaches [53].

Another example is from India’s PLURAL initiative, where global health NGOs and academic institutions (the George Institute, Resolve to Save Lives, and local partners) are collaborating with government agencies to introduce low-sodium salt. In formative research, PLURAL used community workshops and meetings with village leaders to improve acceptance of salt substitutes [54,55]. The investigators found that initially, awareness of low-sodium salt was almost nil and there were misconceptions. By involving community leaders and frontline health workers in education campaigns, they observed greater willingness among households to try the product. This partnership approach—essentially an alliance of an NGO-backed research team with local health authorities and community influencers—is helping deliver the intervention in a culturally sensitive way. NGOs can also assist with subsidizing the price of salt substitutes in such pilots (since cost is a major constraint noted in India), at least until economies of scale or government price controls kick in [55].

Public–private partnerships with food manufacturers: Engaging food manufacturers and the salt industry itself is another critical avenue. In many low-income countries, the national salt market is often dominated by a few large producers (sometimes government-run). Bringing these producers on board to make and distribute low-sodium salt at scale is essential. China provides a leading example: the state-owned China National Salt Corporation has been exploring production of potassium-enriched salt and working with health authorities to market it as a “healthy salt” [56]. This is akin to how iodized salt was rolled out—by mandating or incentivizing all salt producers to add iodine. A 2024 report in Advances in Nutrition outlined a vision for “switching the world’s salt supply” by applying the lessons of universal salt iodization to potassium enrichment [57].

Even at a smaller scale, engaging local food companies can amplify impact. For instance, in Finland’s salt reduction program, collaboration with bakeries, dairy companies, and even fast-food outlets was pivotal. Many companies reformulated recipes to use mineral salt in place of regular salt—not just for table use, but within processed foods. As noted, McDonald’s Finland switched to a potassium-enriched salt for its hamburgers decades ago [42], after public health advocates negotiated with them. Partnerships with international donors can support initial implementation. The NIH’s Fogarty International Center and the National Heart, Lung, and Blood Institute (NHLBI) were key funders of the Peru salt substitute trial [58], demonstrating how research grants can jump-start local action. Similarly, the Resolve to Save Lives initiative (an NGO led by Vital Strategies) is actively working with governments in places like China, India, and Nigeria to promote sodium reduction—including evaluation of low-sodium salt substitutes as a cost-effective intervention [59]. These global NGOs often provide technical expertise, seed funding, and policy advocacy that empower local ministries to act.

Overcoming supply and cost barriers: A recurring challenge in low-income settings is ensuring a stable supply of potassium chloride and keeping the product affordable. Partnerships with the chemical industry (which produces KCl) can be explored. For instance, India has large potassium fertilizer companies; a creative partnership could involve those companies producing food-grade KCl as a by-product and packaging it for culinary use. Government subsidies or social enterprise models might be needed initially. The Peru Salt Liz project managed to offer the salt substitute free during the trial—post-trial, they have considered micro-business models where local entrepreneurs could sell the product at low margin, possibly supported by microfinance or NGO credit. Engaging the private sector in distribution (small shops, market vendors) is crucial, as seen in Peru where even the local shopkeepers became advocates (one store owner voluntarily removed regular salt from shelves once Salt Liz became popular) [52].

4. Discussion

Salt substitutes (potassium- and magnesium-enriched salts) have been shown to lower systolic and diastolic blood pressure. A study conducted on six cohorts from five randomized controlled trials, including 1974 participants, showed a reduction in systolic blood pressure (SBP) reduction by 4.9 mm Hg and Diastolic blood pressure (DBP) reduction by 1.5 mm Hg. These findings support global efforts to develop solutions for normal salt replacement [21].

Further proving the blood pressure-lowering effect was a study conducted in 48 elderly facilities in China involving 1612 residents (55 or older) who used the salt substitute 62.5% NaCl and 25% KCl. Participants using salt substitutes experienced a significant reduction in SBP by 7.1 mmHg and DBP by 1.9 mmHg. The salt substitute group also had approximately 40% fewer cardiovascular events than the other group [22].

Another Study conducted in Peru revealed that intervention with 75% NaCl and 25% KCl led to a modest yet statistically significant reduction in blood pressure. On average, systolic blood pressure decreased by 1.29 mm Hg and diastolic blood pressure by 0.76 mm Hg. It was also revealed that, among individuals without hypertension, the risk of developing hypertension decreased by 51%. The study also demonstrated the protective effects of salt substitutes on total mortality, cardiovascular mortality, and cardiovascular events [23].

Salt substitution could be a simple, low-cost strategy for reducing cardiovascular events. The SSaSS trial, a simple randomized trial conducted in rural China, showed a significant reductions in stroke by 14%, major cardiovascular events by 13%, and all-cause mortality by 12%. However, this brings the challenge that the study was conducted in China and cannot be generalized to the world [11]. Although these findings are convincing, further studies are needed, and comprehensive data are available to prove the long-term effects of salt substitutes on cardiovascular health.

4.1. Safety Challenges and Mitigation Strategies

The use of salt substitutes has proven to be a promising strategy for reducing sodium intake and protecting against cardiovascular disease. These substitutes can lower blood pressure and reduce the incidence of stroke and heart disease by combining traditional sodium chloride with alternative compounds, such as potassium chloride and magnesium salts. Although the benefits are significant, the adoption of salt substitutes presents several challenges that must be carefully addressed to ensure their safe and effective use [3].

One significant concern is the risk of hyperkalemia and drug interactions. The risk of hyperkalemia is particularly high in patients with chronic kidney disease and heart failure, especially with the use of drugs, such as ACE inhibitors or potassium-sparing diuretics. Potassium-containing salt substitutes pose serious health risks. To mitigate this risk, patients should be screened and educated when they are advised to consume salt substitutes. Serum potassium levels should be monitored regularly, and clear and prominent labeling of potassium content and warnings for at-risk populations should be made on packaging. A structured risk mitigation pathway is essential to address the safety concerns associated with potassium-enriched salt substitutes, particularly the risk of hyperkalemia in high-risk populations, such as those with CKD or RAAS inhibitors. Figure 2 outlines the stepwise approach for the safe implementation of salt substitutes in LMICs. This includes initial population screening, public education and product labeling, laboratory monitoring, and referral for medical evaluation, when necessary.

In contrast, in areas where iodine deficiency is already present, the use of non-iodized salt substitutes can pose new concerns. Iodine is an essential micronutrient and iodine deficiency can lead to thyroid disorders and other diseases. The replacement of iodized table salt with non-iodized alternatives can inadvertently reintroduce iodine deficiency disorders [60]. To prevent this, public health strategies should ensure that salt substitutes are fortified with iodine where necessary. This dual approach of reducing sodium intake while maintaining adequate iodine intake can prevent the emergence of new nutritional challenges. In addition to health risks, taste is also a challenge associated with the use of salt substitutes. Potassium chloride is a primary component for which consumers have complained about a metallic or bitter taste, especially when used in large quantities [61].

In some formulations, magnesium is used for its additional health benefits. However, Magnesium-enriched substitutes may cause diarrhea or discomfort in some individuals. This could become a challenge, especially for people who perceive salt substitutes to be inherently safe and tend to overconsume them [62]. This could be addressed by providing a clear warning on packaging that explains gastrointestinal side effects and by setting safe daily intake limits. The most significant challenge is the limited availability of high-quality data to support comprehensive recommendations for salt substitution. Although existing evidence indicates substantial health benefits, more rigorous clinical research is needed, particularly in diverse populations and vulnerable groups. Increased investment in long-term studies could guide safer product development, support regulatory decision-making, and ultimately reduce healthcare costs by lowering the future burden of noncommunicable diseases [63]. Rural areas have limited access to, and availability of, salt substitutes. There could be affordability issues, whereas urban areas have a wider availability of salt alternatives and purchasing power.

4.2. Policy and Public Health Recommendations

Salt substitution should be incorporated into national nutrition and health policies to help substitutes become available at subsidized rates, especially for people in rural areas and low-income populations. Community health workers can serve as vital agents in distributing salt substitutes and educating households about their proper use. Their existing relationships with local populations make them well-positioned to explain the health benefits of reducing sodium and addressing cultural or practical barriers to adopting salt substitute support change. Cooking demonstrations and community workshops can be organized to demonstrate how salt substitutes can be used in local recipes.

In addition to integrating salt substitutes into national health policies, governments can promote reformulation of the food industry. Because salt is used as a preservative, a large amount of dietary sodium originates from processed and packaged foods. Therefore, national policies should encourage food manufacturers to reduce the sodium content in their products and use approved salt substitutes where appropriate. To ensure consumer safety, the ingredients of salt substitutes must be regulated. Regulatory bodies should set standards for permissible ingredient levels and require clear packaging labels.

Interventions at the household level, such as behavior changes, lifestyle adjustments, and meal planning, have been shown to be highly effective for individuals, helping lower the risk of diseases [64]. However, systemic interventions such as food reformulation often yield better results. These changes are especially beneficial for lower-income groups, who are more affected by price fluctuations and frequently lack access to nutritional education. Modifying the food environment can encourage healthier choices among various demographic groups. Additionally, institutionalized changes brought about by food reforms tend to have a lasting impact. A good example of this could be Denmark’s Fat Tax Implementation in 2011; this tax led to a 4% decrease in saturated fat purchases and a 10–15% reduction in fat consumption [65]. A multi-sectoral approach is vital. Salt reduction efforts should involve collaboration among health ministries, the education sector, and the agricultural industry.

4.3. LMIC-Specific Barriers and Practical Approaches

This review makes a distinct contribution to the global hypertension and nutrition literature because it uniquely centers on the analysis of the barriers to implementing salt substitution strategies in LMICs, which are often underrepresented in discussions.

This review highlights LMIC-specific obstacles, including Economic Constraints such as the limited affordability of potassium-enriched salt for low-income households and the absence of government subsidies. There are regulatory gaps in food policy frameworks regulating salt content, and there are no mandatory food labeling laws. Many countries, particularly LMICs, lack comprehensive food policy frameworks that regulate salt content in processed foods.

The absence of mandatory food labeling laws makes it difficult for consumers to make informed choices regarding their sodium intake. It also proposes practical tailored solutions to overcome these barriers. It recommends integrating salt substitution into national health strategies and using community health workers for distribution and education. Subsidies and tiered pricing models can improve affordability, while culturally sensitive messaging can enhance public acceptance.

4.4. Conflicts of Interest and Transparency

Most major outcome trials, including SSaSS, were publicly funded, not supported by the salt industry, which is reassuring. However, as LSSS scale, research and commercialization may overlap. Industry involvement, whether through product supply, education campaigns, or sponsoring studies, requires strict transparency. Trials should disclose funding sources and ensure independent analysis, with oversight to avoid bias. While basic KCl salts are generic, some blends are patented; if these are tested, investigators must declare financial ties. Historical examples such as Finland’s Pansalt highlight the need for independent evaluation. In low-income settings, conflicts could arise if officials, NGOs, or suppliers have financial stakes, making community oversight essential.

Evidence to date shows no compromise of scientific findings, and blood pressure and stroke benefits are consistent across independently funded studies. Still, future work should involve neutral third parties such as WHO or academic centers in design and monitoring. If industry provides products or distribution, agreements must safeguard objective evaluation and publication regardless of results.

4.5. Limitations

Most salt substitute trials have been short-term (months to a few years). The largest, SSaSS, lasted 5 years, but we still lack data in use over decades. Long-term adherence, unforeseen effects, and safety in widespread use remain uncertain. Generalizability is also limited: most studies were in rural China or specific groups (older men in institutions). Evidence is scarce in some high-sodium regions (Africa). Publication bias is possible, with positive results more likely to be reported. Implementation is another concern. In nearly all successful trials, substitutes were provided free or subsidized. Real-world programs must address cost, supply, and cultural acceptance, which may hinder large-scale rollout. Most studies measured surrogate outcomes like blood pressure, only a few assessed clinical endpoints. Evidence for reduced mortality mainly comes from one Chinese trial, so replication in diverse populations is needed. Finally, safety over the long term is unclear. People with unrecognized kidney disease may face higher risk of hyperkalemia. Trials excluded severe CKD and showed no short-term harm, but ongoing monitoring and population-level safeguards will be important.

4.6. Future Research Directions

Studies on multiple arenas of salt substitutes need to be conducted because of gaps in the available literature. Although preliminary research has demonstrated potential benefits, many important areas remain unexplored, including clinical trials, toxicological assessments, public health implementation studies, policy development, and regulatory recommendations that may remain incomplete. The long-term safety outcomes and health effects of potassium-enriched salts, particularly in LMICs, need to be studied. Longitudinal cohort studies can assess the impact of salt substitution on morbidity, mortality, and quality of life over 5–10 years, especially in populations with chronic kidney disease, heart failure, or potassium-retaining medications such as ACE inhibitors and potassium-sparing diuretics.

Because the current data on the use of salt substitutes in various populations are limited and restricted to only certain regions of the world, randomized controlled trials (RCTs) need to be expanded to underrepresented regions in sub-Saharan Africa, Latin America, and South Asia to validate generalizability. Their effectiveness according to age, sex, ethnicity, and baseline sodium/potassium intake needs to be studied.

The cost-effectiveness of salt substitutes and cost–benefit analysis compared to pharmacological interventions for lowering blood pressure need to be studied to formulate broader public health strategies for hypertension control. This can help in potential health system savings from reduced cardiovascular disease burden due to widespread salt substitute adoption.

5. Conclusions

Salt substitutes are an effective and affordable strategy to reduce blood pressure and cardiovascular risk, especially in low- and middle-income countries, where hypertension is highly prevalent. Evidence shows consistent reductions in BP and promising outcomes for stroke and mortality prevention. However, implementation challenges (including cost, limited availability, safety concerns in high-risk groups, and lack of iodine fortification) must be addressed.

For successful adoption, salt substitutes should be integrated into national policies, supported by subsidies, clear labeling, and public education. Community health workers and local campaigns can play key roles in improving awareness and access. Future research should focus on long-term safety, cost-effectiveness, and practical implementation in diverse LMIC settings to ensure equitable and safe use.