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Salt

Pooled trials show eating less salt lowers blood pressure, by about 4 mmHg systolic for a 130 mmol daily cut, more in people with hypertension. A potassium-enriched salt substitute cut strokes, heart events and deaths in one 20,995-person trial. Low-sodium diets raised renin, aldosterone, cholesterol and triglycerides slightly, and substitutes raised blood potassium slightly.

Add to Bio HackChecked 2026-11-13
Status
A food, not a regulated health product. The FDA Daily Value for sodium is less than 2,300 mg a day, and the FDA states the Dietary Guidelines for Americans advise adults to limit sodium to less than 2,300 mg a day [1]. The World Health Organization's figure for adults is less than 2,000 mg of sodium a day, about 5 g of salt [2].
Also called
table salt, sodium chloride, NaCl, dietary sodium, sodium intake, low-salt diet, low-sodium diet, salt substitute, potassium-enriched salt, sea salt, pink Himalayan salt, kosher salt
Studied for
blood pressure, heart health, stroke, kidney health, bloating, water retention, minerals in sea salt and pink salt, electrolytes

Strong several reviews agree · Moderate one review or consistent trials · Limited one or a few small studies · Untested no study in people, listed with what it rests on

Shown to help3

Reported risks3

What it was studied for, and what was found

Shown to help3

Strong

Blood pressure, from eating less salt

Shown to lower blood pressure, by about 4 mmHg systolic for a 130 mmol daily sodium cut, more in people with hypertension and in older adults.

Compared with usual sodium intake [3]; usual salt intake [4]; a high-sodium diet [5]; higher sodium intakes in the same trials [6]

The numbers and sources
Effect
Across 133 trials, a 130 mmol cut in 24-hour urinary sodium lowered systolic pressure by 4.26 mmHg (95% CI 3.62 to 4.89) and diastolic by 2.07 mmHg (1.67 to 2.48). Each 50 mmol cut lowered systolic pressure 1.10 mmHg, with larger falls in older people, non-white populations and those with higher starting pressure. Trials under 15 days showed less than half the effect of longer trials [3]. A Cochrane review of 34 trials found a 4.4 g a day salt cut lowered systolic pressure 5.39 mmHg in people with hypertension and 2.42 mmHg in people without it [4]. In white participants, cutting sodium from 203 to 65 mmol a day lowered systolic pressure 5.71 mmHg with hypertension and 1.14 mmHg without it, and did not change diastolic pressure in people with normal blood pressure [5]. A dose-response analysis of 85 trials found a roughly straight-line relation between sodium intake and blood pressure from 0.4 to 7.6 g a day, with no flattening at the lowest intakes [6].
Population
12,197 adults in 133 randomized trials [3]. 3,230 adults in 34 trials of at least 4 weeks [4]. About 10,000 white participants in up to 96 trials, plus black and Asian participants in smaller sets of trials [5]. 85 trials of at least 4 weeks [6].
Sources
[3], [4], [5], [6]
Caveats
The same trials appear in several of these reviews. Effects in people without hypertension were small, and evidence in black and Asian participants was rated low to moderate quality [5]. Heterogeneity was high in [4].
Strong

Blood pressure, with salt substitutes

Shown to lower systolic blood pressure by about 4.4 to 4.8 mmHg with potassium-enriched salt substitutes in place of regular salt, in two meta-analyses.

Compared with regular salt [7][8]; usual salt [9]

The numbers and sources
Effect
A Cochrane review found low-sodium salt substitutes lowered systolic pressure by 4.76 mmHg (95% CI 3.50 to 6.01, 20 trials) and diastolic pressure by 2.43 mmHg (95% CI 1.36 to 3.50, 19 trials) [7]. A network meta-analysis of 34 trials found moderate-potassium, low-sodium substitutes (25% to 40% potassium chloride) lowered systolic pressure by 4.39 to 4.64 mmHg [8]. In older adults with normal blood pressure in care homes, new hypertension was less frequent with a salt substitute over 2 years (11.7 against 24.3 per 100 person-years, HR 0.60, 95% CI 0.39 to 0.92), with a net systolic difference of 8.0 mmHg [9].
Population
21,414 adults in 20 trials [7]. 37,063 participants in 34 trials in 15 countries, mean age 62 [8]. 611 Chinese older adults with normal blood pressure in 48 care facilities [9].
Sources
[7], [8], [9]
Caveats
The two reviews share most of their trials. All trials excluded people for whom extra potassium is known to be harmful [7]. The care home analysis was post hoc, and a salt company supplied the salt [9].
Moderate

Stroke, heart events and death, with salt substitutes

Shown to lower stroke by 14%, major heart events by 13% and death by 12% in one large trial of older Chinese adults, an effect that drives pooled results.

Compared with regular salt [10][7][8]

The numbers and sources
Effect
Over a mean 4.74 years, stroke was less frequent with a 75% sodium chloride, 25% potassium chloride substitute than with regular salt (29.14 against 33.65 events per 1,000 person-years, rate ratio 0.86, 95% CI 0.77 to 0.96), as were major cardiovascular events (rate ratio 0.87, 95% CI 0.80 to 0.94) and death (rate ratio 0.88, 95% CI 0.82 to 0.95) [10]. A Cochrane review rated substitutes as probably reducing non-fatal stroke, non-fatal acute coronary syndrome and cardiovascular death slightly, by 20, 150 and 180 fewer per 100,000 person-years [7]. A network meta-analysis estimated 7 to 17 fewer deaths per 1,000 people, and found that removing the large Chinese trial left no significant effect on death from any cause [8].
Population
20,995 people in 600 Chinese villages with past stroke, or aged 60 or older with high blood pressure, mean age 65.4, 49.5% women [10]. Adults in 3 trials with event data [7]. 34 trials [8].
Sources
[10], [7], [8]
Caveats
One open-label trial in rural China, where most salt is added at home, carries the pooled results, and no trial outside China reported deaths [8]. The reviewers describe very limited generalizability beyond Chinese populations who add much of their salt at home [8].

Mixed results3

Moderate

Heart attack and stroke, from eating less salt

Mixed results: pooled trials found about 23% fewer cardiovascular events, which reviewers called underpowered and driven by one retirement home trial. A trial follow-up found 25% fewer.

Compared with control groups without salt reduction advice or substitution [11]; control groups without sodium reduction counseling [12]

The numbers and sources
Effect
A Cochrane review of 8 trials found weak evidence of fewer cardiovascular events with less salt (pooled RR 0.77, 95% CI 0.63 to 0.95, 6 trials, 5,912 people), driven by one trial in which retirement home kitchens cut salt. Results for cardiovascular death in people with hypertension were imprecise (RR 0.67, 95% CI 0.45 to 1.01) [11]. Ten to 15 years after two sodium reduction trials in adults with prehypertension, cardiovascular events were 25% less frequent in the former intervention groups (RR 0.75, 95% CI 0.57 to 0.99) [12].
Population
7,284 adults in 8 trials of 6 to 36 months [11]. 3,126 adults aged 30 to 54 with prehypertension, with event data from 2,415 [12].
Sources
[11], [12]
Caveats
The Cochrane authors state their review lacked the power to confirm clinically important effects [11]. The trial follow-up was observational after the trials ended, with 77% of participants reporting outcomes [12].
Moderate

Death from any cause

Mixed results: salt reduction advice trials found no fewer deaths, one salt substitute trial found 12% fewer, and one cohort linked both low and high intakes to more deaths.

Compared with control groups without salt reduction advice or substitution [11]; control groups without sodium reduction counseling [12]; regular salt [10]; people excreting 4.00 to 5.99 g of sodium a day [13]

The numbers and sources
Effect
In trials of salt reduction advice, death did not fall in people with hypertension (RR 1.00, 95% CI 0.86 to 1.15) and the estimate in people without it was imprecise (RR 0.67, 95% CI 0.40 to 1.12) [11]. In the trial follow-up, deaths did not differ (RR 0.80, 95% CI 0.51 to 1.26) [12]. In one large trial of a salt substitute, deaths were fewer (rate ratio 0.88, 95% CI 0.82 to 0.95) [10]. In a cohort of 101,945 adults in 17 countries, estimated sodium of 7 g a day or more (OR 1.15, 95% CI 1.02 to 1.30) and below 3 g a day (OR 1.27, 95% CI 1.12 to 1.44) were both linked to more deaths or cardiovascular events than 4 to 6 g a day [13].
Population
3,518 adults without and 3,085 with hypertension in trials [11]. 3,126 adults with prehypertension [12]. 20,995 older Chinese adults [10]. 101,945 adults in 17 countries followed a mean 3.7 years [13].
Sources
[11], [12], [10], [13]
Caveats
The cohort estimated sodium from one morning urine sample, and people eating little may be sicker to begin with, so reverse causation and confounding are possible [13]. Advice trials cut salt less than the substitute trial.
Limited

Heart disease and stroke, in cohorts by sodium intake

Mixed results: in cohorts, higher measured sodium was linked to more cardiovascular events, while one large study found the link only where average intake exceeded 5 g a day.

Compared with people in the lowest quarter of sodium excretion [14]; communities with lower mean sodium intake [15]; people excreting 4.00 to 5.99 g of sodium a day [13]

The numbers and sources
Effect
In 10,709 adults with at least two 24-hour urine collections, the highest quarter of sodium excretion was linked to more cardiovascular events than the lowest (HR 1.60, 95% CI 1.19 to 2.14), and each extra 1,000 mg a day to 18% more (HR 1.18, 95% CI 1.08 to 1.29) [14]. Across 255 communities, sodium was linked to cardiovascular events and stroke only where mean intake was above 5 g a day, and in the lowest third of intake (mean 4.04 g a day) higher sodium was linked to fewer events [15]. In the same program, intakes below 3 g and above 7 g a day were both linked to more events than 4 to 6 g [13].
Population
10,709 adults in 6 cohorts, median follow-up 8.8 years [14]. 82,544 adults in 255 communities in 18 countries, median 8.1 years [15]. 101,945 adults in 17 countries [13].
Sources
[14], [15], [13]
Caveats
Observational. Studies using several 24-hour urine samples [14] found a straight-line link, while those using one morning sample [15][13] found a curve, and how sodium is measured is part of the disagreement. Confounding and reverse causation are possible.

Claimed, not studied in people1

Untested

Minerals in sea salt and pink salt

Not studied in people. Lab analysis of 31 pink salts found minerals in amounts that would need over 30 g of salt a day to matter.

No study in people. This rests on lab studies.

The numbers and sources
Effect
Mass spectrometry of 31 pink salt samples sold in Australia found wide variation in minerals, more in Himalayan, flake and darker salts. The authors calculated that more than 30 g a day, about 6 teaspoons, would be needed for a meaningful mineral contribution. One sample exceeded the national limit for lead [16].
Population
31 retail pink salt samples and one iodized table salt [16].
Sources
[16]
Caveats
A product analysis with no people studied. Mineral content says nothing about effects on health.

Amounts studied

Salt reduction trials cut 24-hour urinary sodium by a mean of 130 mmol [3], or by 75 mmol, about 4.4 g of salt a day [4]. The Cochrane comparison of low and high sodium diets moved white participants from 203 to 65 mmol a day [5]. Trials in the dose-response analysis ranged from 0.4 to 7.6 g of sodium a day for 4 weeks to 36 months [6]. Salt substitutes replaced 3% to 77% of sodium chloride, mostly with potassium salts [7]. The large stroke trial used 75% sodium chloride and 25% potassium chloride for a mean 4.74 years [10], and the care home trial used 62.5% sodium chloride, 25% potassium chloride and 12.5% flavorings for 2 years [9]. The trial follow-up studied counseling that cut sodium by 33 to 44 mmol a day for 18 to 48 months [12].

Risks

Reported risks3

LimitedHow often is not known

Stomach cancer at higher salt intakes

Linked to stomach cancer in cohorts, with 68% higher risk at high against low intake. A salt substitute trial found a nonsignificant trend toward fewer stomach cancers.

The numbers and sources
How common
How often is not known: the sources give no rate.
Effect
Pooled across 7 prospective studies, high salt intake was linked to more stomach cancer than low intake (RR 1.68, 95% CI 1.17 to 2.41), and moderately high intake too (RR 1.41, 95% CI 1.03 to 1.93), with a stronger link in Japanese populations [17]. In the large salt substitute trial, stomach cancer did not differ significantly (RR 0.77, 95% CI 0.54 to 1.08) [18].
Population
268,718 adults with 1,474 cases, followed 6 to 15 years [17]. 20,996 older Chinese adults, mean 4.7 years, 212 stomach cancers [18].
Sources
[17], [18]
Caveats
Observational studies, often measuring salty foods rather than sodium, open to confounding. The trial analysis was post hoc [18].
ModerateHow often is not known

Hormone and blood fat changes on low-sodium diets

Shown to raise renin, aldosterone, noradrenaline, total cholesterol and triglycerides slightly when sodium was cut sharply in trials. LDL and HDL cholesterol did not change significantly.

The numbers and sources
How common
How often is not known: the sources give no rate.
Effect
During sodium reduction, renin rose 1.56 ng/mL/hour (82 trials), aldosterone 104 pg/mL (66 trials) and noradrenaline 62.3 pg/mL (35 trials). Total cholesterol rose 5.19 mg/dL (95% CI 2.1 to 8.3, 27 trials) and triglycerides 7.10 mg/dL (95% CI 3.1 to 11.1, 20 trials). LDL cholesterol changed by 2.46 mg/dL (95% CI -1 to 5.9) and HDL by -0.3 mg/dL (95% CI -1.66 to 1.05) [5].
Population
917 participants for cholesterol, 712 for triglycerides and 2,904 for renin, in randomized trials of low against high sodium diets [5].
Sources
[5]
Caveats
Many trials were short and cut sodium further than guidelines ask. The review authors note these changes were more consistent than the blood pressure effect in people with normal blood pressure [5].
ModerateHow often is not known

Higher blood potassium with salt substitutes

Shown to raise blood potassium slightly, by 0.12 mmol/L, in trials that excluded people at risk. Serious high potassium events did not differ from regular salt.

The numbers and sources
How common
How often is not known: the sources give no rate.
Effect
Low-sodium salt substitutes raised blood potassium by 0.12 mmol/L (95% CI 0.07 to 0.18, 6 trials) and made little or no difference to hyperkalemia (4 more per 100,000, 95% CI 47 fewer to 121 more, 5 trials) [7]. In the large trial, serious adverse events attributed to hyperkalemia occurred at 3.35 against 3.30 per 1,000 person-years (rate ratio 1.04, 95% CI 0.80 to 1.37) [10]. A network meta-analysis found no substitute increased adverse events or withdrawals [8].
Population
784 adults for blood potassium and 22,849 for hyperkalemia [7]. 20,995 older Chinese adults [10]. 34 trials [8].
Sources
[7], [10], [8]
Caveats
Every trial excluded people for whom more potassium is known to be harmful, so these results do not cover them [7]. The network meta-analysis authors limit their safety conclusion to people without kidney impairment [8].

Checked, no increase found1

Limited

Low blood pressure episodes with salt substitutes

One trial analysis in older adults with normal blood pressure found low blood pressure episodes did not rise with a salt substitute over 2 years.

The numbers and sources
How common
How often is not known: the sources give no rate.
Effect
Hypotension episodes occurred at 9.0 per 100 person-years with the salt substitute and 9.7 with usual salt (P = 0.76) [9].
Population
611 Chinese older adults with normal blood pressure in 48 care facilities [9].
Sources
[9]
Caveats
A post hoc analysis of a cluster-randomized trial.

Claims tested and not found

  1. That cutting salt lowers blood pressure only in people with hypertension. Systolic pressure fell 2.42 mmHg in people without hypertension in a Cochrane review [4], and 1.14 mmHg in white participants with normal blood pressure in another [5], less than in people with hypertension.
  2. That the blood pressure effect of cutting salt flattens out at low intakes. A dose-response analysis of 85 trials found no flattening at the lowest intakes studied [6].

Related

Sodium levelDASH dietPotassium

Sources

  1. U.S. Food and Drug Administration. Sodium in Your Diet. 2024. https://www.fda.gov/food/nutrition-education-resources-materials/sodium-your-diet
  2. World Health Organization. Sodium reduction. Fact sheet. 2026. https://www.who.int/news-room/fact-sheets/detail/sodium-reduction
  3. Huang L, Trieu K, Yoshimura S, et al. Effect of dose and duration of reduction in dietary sodium on blood pressure levels: systematic review and meta-analysis of randomised trials. BMJ. 2020. https://doi.org/10.1136/bmj.m315
  4. He FJ, Li J, MacGregor GA. Effect of longer term modest salt reduction on blood pressure: Cochrane systematic review and meta-analysis of randomised trials. BMJ. 2013. https://doi.org/10.1136/bmj.f1325
  5. Graudal NA, Hubeck-Graudal T, Jurgens G. Effects of low sodium diet versus high sodium diet on blood pressure, renin, aldosterone, catecholamines, cholesterol, and triglyceride. Cochrane Database of Systematic Reviews. 2020. https://doi.org/10.1002/14651858.cd004022.pub5
  6. Filippini T, Malavolti M, Whelton PK, et al. Blood Pressure Effects of Sodium Reduction: Dose-Response Meta-Analysis of Experimental Studies. Circulation. 2021. https://doi.org/10.1161/circulationaha.120.050371
  7. Brand A, Visser ME, Schoonees A, Naude CE. Replacing salt with low-sodium salt substitutes (LSSS) for cardiovascular health in adults, children and pregnant women. Cochrane Database of Systematic Reviews. 2022. https://doi.org/10.1002/14651858.cd015207
  8. Lai H, Nesrallah G, Guyatt GH, et al. Comparative effects of salt substitutes on blood pressure, cardiovascular events and mortality: a systematic review and network meta-analysis. BMC Medicine. 2026. https://doi.org/10.1186/s12916-026-04635-z
  9. Zhang X, Yuan Y, Li C, et al. Effect of a Salt Substitute on Incidence of Hypertension and Hypotension Among Normotensive Adults. Journal of the American College of Cardiology. 2024. https://doi.org/10.1016/j.jacc.2023.12.013
  10. Neal B, Wu Y, Feng X, et al. Effect of Salt Substitution on Cardiovascular Events and Death. New England Journal of Medicine. 2021. https://doi.org/10.1056/nejmoa2105675
  11. Adler AJ, Taylor F, Martin N, et al. Reduced dietary salt for the prevention of cardiovascular disease. Cochrane Database of Systematic Reviews. 2014. https://doi.org/10.1002/14651858.cd009217.pub3
  12. Cook NR, Cutler JA, Obarzanek E, et al. Long term effects of dietary sodium reduction on cardiovascular disease outcomes: observational follow-up of the trials of hypertension prevention (TOHP). BMJ. 2007. https://doi.org/10.1136/bmj.39147.604896.55
  13. O'Donnell M, Mente A, Rangarajan S, et al. Urinary sodium and potassium excretion, mortality, and cardiovascular events. New England Journal of Medicine. 2014. https://doi.org/10.1056/nejmoa1311889
  14. Ma Y, He FJ, Sun Q, et al. 24-Hour Urinary Sodium and Potassium Excretion and Cardiovascular Risk. New England Journal of Medicine. 2022. https://doi.org/10.1056/nejmoa2109794
  15. Mente A, O'Donnell M, Rangarajan S, et al. Urinary sodium excretion, blood pressure, cardiovascular disease, and mortality: a community-level prospective epidemiological cohort study. The Lancet. 2018. https://doi.org/10.1016/s0140-6736(18)31376-x
  16. Fayet-Moore F, Wibisono C, Carr P, et al. An Analysis of the Mineral Composition of Pink Salt Available in Australia. Foods. 2020. https://doi.org/10.3390/foods9101490
  17. D'Elia L, Rossi G, Ippolito R, et al. Habitual salt intake and risk of gastric cancer: a meta-analysis of prospective studies. Clinical Nutrition. 2012. https://doi.org/10.1016/j.clnu.2012.01.003
  18. Zhang X, Yin X, Yap ML, et al. Effect of sodium-reduced potassium-enriched salt substitutes on stomach cancer: the Salt Substitute and Stroke Study (SSaSS). BMC Medicine. 2025. https://doi.org/10.1186/s12916-025-04068-0

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