High sodium intake
Sodium is the part of table salt linked with higher blood pressure when people eat a lot of it. The World Health Organization advises adults to keep sodium below 2 grams a day, which is about 5 grams of salt. It estimated that average sodium intake worldwide in 2019 was more than double that limit.
Also called High salt intake
- Risk factor
- In this atlas
Overview
Technical summary
Exposure defined here as dietary sodium above the WHO limit of less than 2 g a day of sodium (5 g of salt) in adults, a strong WHO recommendation. The MeSH heading "Sodium Chloride, Dietary" names the substance, not an intake level. Evidence recorded here is the WHO 2012 summary of observational associations (very low to low quality ratings) and the WHO 2025 restatement of the limit. The WHO 2012 text also reports an association with hypertension, recorded as a discovery link because the passage does not state raised risk. SSaSS tested a different thing: replacing salt with a potassium-containing substitute.
Definition
Dietary sodium intake above the WHO limit for adults of less than 2 g of sodium (5 g of salt) a day.
- Type
- Exposure
Contexts
Context Adults in general populations (WHO sodium intake guidance, 2012 and its 2025 restatement)
- Recipient
- Adult
- Population
- Adults in the general population, with or without hypertension. The 2012 text also applies the recommendation to pregnant and lactating women; that item belongs to the maternal atlas and is outside this context. The 2012 text excludes people with illnesses or medicines that can cause low blood sodium or sudden fluid retention, and people who need physician-supervised diets, such as people with heart failure or type 1 diabetes.
- Care setting
- Not stated as a care setting. The guidance covers everyday dietary sodium intake.
- Geography
- Global guidance. The cohort studies in the 2012 meta-analysis were conducted in Europe, Japan and the United States.
- Life stage
- Adult; the sources set no age bounds in the passages read
- Follow-up
- Not applicable to the recommendation. The cohort studies in the 2012 summary followed adults for 3.8 to 22 years.
Eligibility: 2 inclusion criteria; 3 exclusion criteria
- Included
- Adults
- With or without hypertension
- Excluded
- Illnesses or medicines that can cause low blood sodium or sudden fluid retention
- People who need physician-supervised diets (for example heart failure, type 1 diabetes)
- Pregnancy and lactation: named by the 2012 text, outside this context
Claims and evidence
Context Adults in general populations (WHO sodium intake guidance, 2012 and its 2025 restatement)
- Recipient
- Adult
- Population
- Adults in the general population, with or without hypertension. The 2012 text also applies the recommendation to pregnant and lactating women; that item belongs to the maternal atlas and is outside this context. The 2012 text excludes people with illnesses or medicines that can cause low blood sodium or sudden fluid retention, and people who need physician-supervised diets, such as people with heart failure or type 1 diabetes.
- Care setting
- Not stated as a care setting. The guidance covers everyday dietary sodium intake.
- Geography
- Global guidance. The cohort studies in the 2012 meta-analysis were conducted in Europe, Japan and the United States.
- Life stage
- Adult; the sources set no age bounds in the passages read
- Follow-up
- Not applicable to the recommendation. The cohort studies in the 2012 summary followed adults for 3.8 to 22 years.
Eligibility: 2 inclusion criteria; 3 exclusion criteria
- Included
- Adults
- With or without hypertension
- Excluded
- Illnesses or medicines that can cause low blood sodium or sudden fluid retention
- People who need physician-supervised diets (for example heart failure, type 1 diabetes)
- Pregnancy and lactation: named by the 2012 text, outside this context
The WHO 2012 sodium guideline reports that, in cohort studies of adults, people who ate more sodium had more strokes than people who ate the least. The pooled risk ratio was 1.24 (95% CI 1.08 to 1.43) for stroke and 1.63 (95% CI 1.27 to 2.10) for fatal stroke. WHO rated the evidence very low quality for stroke and low quality for fatal stroke. These are observational comparisons of higher and lower intake groups.
Applies to Adult- Adults in the general population, with or without hypertension. The 2012 text also applies the recommendation to pregnant and lactating women; that item belongs to the maternal atlas and is outside this context. The 2012 text excludes people with illnesses or medicines that can cause low blood sodium or sudden fluid retention, and people who need physician-supervised diets, such as people with heart failure or type 1 diabetes.
- Not stated as a care setting. The guidance covers everyday dietary sodium intake.
- Global guidance. The cohort studies in the 2012 meta-analysis were conducted in Europe, Japan and the United States.
- Adult; the sources set no age bounds in the passages read
- Certainty method
- WHO's own GRADE quality ratings, printed in the 2012 guideline: very low for the stroke result and low for the fatal stroke result. The claim takes the lower rating.
- Limitations
- Observational cohort data with very low to low quality ratings from WHO. Groups were compared on sodium intake, not on a change in intake, and the guideline notes that some cohort studies found no link, an inverse link (higher intake with lower risk) or a J-shaped curve. Intake ranges differed widely between studies, and the lowest-intake groups in some studies ate as much as 4 g of sodium a day, so the comparison is not intake above against below the WHO limit of 2 g. Nothing here shows that cutting sodium prevents strokes; the SSaSS claim concerns a different intervention.
- Last checked
- Not recorded
- Next evidence check due
- Not scheduled
Sources and citations (5)
-
Supports Guideline: Sodium intake for adults and children
- Locator
- Executive summary, Background, paragraph 1
- How it applies
- WHO links high sodium intake with hypertension, cardiovascular disease and stroke.
- Retrieved
- Source effective date
- Not reported
- Source state
- Current
- Snapshot hash
1f42c807c29ae255b31554afafaed683d5598414a1e5cc2a4b89190c72e2f369- Reuse basis
- All rights reserved, per the copyright page. Public text is cite_only: the copyright page says all rights reserved, so the terms do not clearly allow quotation (your WHO decision on issue 2 covers the CC BY-NC-SA guidelines). Easy to change to quote if you decide otherwise. Hash only; the PDF is not committed.
-
Supports Guideline: Sodium intake for adults and children
- Locator
- Summary of evidence, page 13, meta-analysis of cohort studies
- How it applies
- Pooled risk ratio for stroke, quality very low.
- Retrieved
- Source effective date
- Not reported
- Source state
- Current
- Snapshot hash
1f42c807c29ae255b31554afafaed683d5598414a1e5cc2a4b89190c72e2f369- Reuse basis
- All rights reserved, per the copyright page. Public text is cite_only: the copyright page says all rights reserved, so the terms do not clearly allow quotation (your WHO decision on issue 2 covers the CC BY-NC-SA guidelines). Easy to change to quote if you decide otherwise. Hash only; the PDF is not committed.
-
Supports Guideline: Sodium intake for adults and children
- Locator
- Summary of evidence, page 13, fatal stroke
- How it applies
- Pooled risk ratio for fatal stroke, quality low.
- Retrieved
- Source effective date
- Not reported
- Source state
- Current
- Snapshot hash
1f42c807c29ae255b31554afafaed683d5598414a1e5cc2a4b89190c72e2f369- Reuse basis
- All rights reserved, per the copyright page. Public text is cite_only: the copyright page says all rights reserved, so the terms do not clearly allow quotation (your WHO decision on issue 2 covers the CC BY-NC-SA guidelines). Easy to change to quote if you decide otherwise. Hash only; the PDF is not committed.
-
Background Guideline: Sodium intake for adults and children
- Locator
- Summary of evidence, page 13, cohort studies and comparison groups
- How it applies
- Fifteen cohort studies in adults, reference group lowest intake, comparison group generally highest.
- Retrieved
- Source effective date
- Not reported
- Source state
- Current
- Snapshot hash
1f42c807c29ae255b31554afafaed683d5598414a1e5cc2a4b89190c72e2f369- Reuse basis
- All rights reserved, per the copyright page. Public text is cite_only: the copyright page says all rights reserved, so the terms do not clearly allow quotation (your WHO decision on issue 2 covers the CC BY-NC-SA guidelines). Easy to change to quote if you decide otherwise. Hash only; the PDF is not committed.
-
Background Guideline: Sodium intake for adults and children
- Locator
- Background, page 6
- How it applies
- Most cohort studies reported a direct relationship, but not all.
- Retrieved
- Source effective date
- Not reported
- Source state
- Current
- Snapshot hash
1f42c807c29ae255b31554afafaed683d5598414a1e5cc2a4b89190c72e2f369- Reuse basis
- All rights reserved, per the copyright page. Public text is cite_only: the copyright page says all rights reserved, so the terms do not clearly allow quotation (your WHO decision on issue 2 covers the CC BY-NC-SA guidelines). Easy to change to quote if you decide otherwise. Hash only; the PDF is not committed.
WHO recommends that adults reduce sodium intake to below 2 g a day, about 5 g of salt, to lower blood pressure and the risk of heart and blood-vessel disease. WHO calls this a strong recommendation and restates it in its 2025 salt-substitute guideline.
Applies to Adult- Adults in the general population, with or without hypertension. The 2012 text also applies the recommendation to pregnant and lactating women; that item belongs to the maternal atlas and is outside this context. The 2012 text excludes people with illnesses or medicines that can cause low blood sodium or sudden fluid retention, and people who need physician-supervised diets, such as people with heart failure or type 1 diabetes.
- Not stated as a care setting. The guidance covers everyday dietary sodium intake.
- Global guidance. The cohort studies in the 2012 meta-analysis were conducted in Europe, Japan and the United States.
- Adult; the sources set no age bounds in the passages read
- Certainty method
- Not assessed
- Limitations
- The 2025 guideline restates the limit; the strong recommendation itself comes from the 2012 WHO guideline, which this claim cites. In its recommendation remarks that PDF rates the evidence on sodium and blood pressure as high quality, and the evidence on sodium and all-cause mortality, cardiovascular disease, stroke and coronary heart disease as lower quality. Its Annex 1 GRADE table for intake below 2 g a day against 2 g or more in adults says that no study addressed that question with cardiovascular disease or stroke as its outcome. The table rates resting systolic blood pressure at 3.47 mmHg lower from 2 studies, graded high, and has no estimate for any cardiovascular event outcome. A footnote to that table reports 5 cohort studies that compared the two intake levels, with a risk ratio of 1.30 (1.03 to 1.64) for stroke at 2 g a day or more, and the table gives that cohort result no GRADE rating. Annex 8 of the PDF describes evidence of high and moderate quality that intake below 2 g a day is beneficial for blood pressure and for the risk of cardiovascular disease, stroke and coronary heart disease in adults. It rates the cardiovascular part as moderate quality on the basis of the blood-pressure evidence, citing the well-established link between blood pressure and cardiovascular outcomes. WHO gives no single certainty rating for the 2 g limit, so the certainty stays not assessed. The 2012 text applies the limit to pregnant and lactating women too, which is outside this context. The limit is for general populations and excludes people on supervised diets or with illnesses that affect body sodium.
- Last checked
- Not recorded
- Next evidence check due
- Not scheduled
Sources and citations (8)
-
Supports Use of lower-sodium salt substitutes: WHO guideline
- Locator
- Executive summary, aligned WHO recommendations on sodium intake, page x
- How it applies
- The limit as restated in 2025.
- Retrieved
- Source effective date
- Not reported
- Source state
- Current
- Snapshot hash
e7111969908bbf588c20b457b6f5f26ce16e6d9e023e7e179d8a9c1b54a318a0- Reuse basis
- CC BY-NC-SA 3.0 IGO, stated in the PDF. Short quotations with attribution only, until the atlas settles its public data licence. Hashes only; the page and the PDF are not committed.
-
Supports Use of lower-sodium salt substitutes: WHO guideline
- Locator
- Executive summary, WHO recommendation box, page ix (rationale sentence)
- How it applies
- Why WHO recommends it: blood pressure and cardiovascular risk.
- Retrieved
- Source effective date
- Not reported
- Source state
- Current
- Snapshot hash
e7111969908bbf588c20b457b6f5f26ce16e6d9e023e7e179d8a9c1b54a318a0- Reuse basis
- CC BY-NC-SA 3.0 IGO, stated in the PDF. Short quotations with attribution only, until the atlas settles its public data licence. Hashes only; the page and the PDF are not committed.
-
Background Guideline: Sodium intake for adults and children
- Locator
- Executive summary, Background, paragraph 1
- How it applies
- The 2012 guideline gives 2 g of sodium a day, equal to 5 g of salt.
- Retrieved
- Source effective date
- Not reported
- Source state
- Current
- Snapshot hash
1f42c807c29ae255b31554afafaed683d5598414a1e5cc2a4b89190c72e2f369- Reuse basis
- All rights reserved, per the copyright page. Public text is cite_only: the copyright page says all rights reserved, so the terms do not clearly allow quotation (your WHO decision on issue 2 covers the CC BY-NC-SA guidelines). Easy to change to quote if you decide otherwise. Hash only; the PDF is not committed.
-
Background Guideline: Sodium intake for adults and children
- Locator
- Executive summary, Recommendations remarks, page 3, paragraph 1
- How it applies
- Who the 2012 recommendation applies to and its exceptions.
- Retrieved
- Source effective date
- Not reported
- Source state
- Current
- Snapshot hash
1f42c807c29ae255b31554afafaed683d5598414a1e5cc2a4b89190c72e2f369- Reuse basis
- All rights reserved, per the copyright page. Public text is cite_only: the copyright page says all rights reserved, so the terms do not clearly allow quotation (your WHO decision on issue 2 covers the CC BY-NC-SA guidelines). Easy to change to quote if you decide otherwise. Hash only; the PDF is not committed.
-
Background Guideline: Sodium intake for adults and children
- Locator
- Executive summary, Recommendations remarks, page 3, paragraph 4
- How it applies
- WHO's statement of the quality of the evidence behind the 2012 recommendations.
- Retrieved
- Source effective date
- Not reported
- Source state
- Current
- Snapshot hash
1f42c807c29ae255b31554afafaed683d5598414a1e5cc2a4b89190c72e2f369- Reuse basis
- All rights reserved, per the copyright page. Public text is cite_only: the copyright page says all rights reserved, so the terms do not clearly allow quotation (your WHO decision on issue 2 covers the CC BY-NC-SA guidelines). Easy to change to quote if you decide otherwise. Hash only; the PDF is not committed.
-
Background Guideline: Sodium intake for adults and children
- Locator
- Annex 1, GRADE table for intake below 2 g/day against 2 g/day or more in adults (PDF page 32), outcome rows and notes
- How it applies
- No study had cardiovascular disease or stroke as its outcome; blood pressure rated high; a footnote reports cohort studies.
- Retrieved
- Source effective date
- Not reported
- Source state
- Current
- Snapshot hash
1f42c807c29ae255b31554afafaed683d5598414a1e5cc2a4b89190c72e2f369- Reuse basis
- All rights reserved, per the copyright page. Public text is cite_only: the copyright page says all rights reserved, so the terms do not clearly allow quotation (your WHO decision on issue 2 covers the CC BY-NC-SA guidelines). Easy to change to quote if you decide otherwise. Hash only; the PDF is not committed.
-
Background Guideline: Sodium intake for adults and children
- Locator
- Summary of evidence, page 12, comparison of the lowest with the middle consumption group
- How it applies
- The blood-pressure difference for below 2 g a day, with WHO's high quality rating.
- Retrieved
- Source effective date
- Not reported
- Source state
- Current
- Snapshot hash
1f42c807c29ae255b31554afafaed683d5598414a1e5cc2a4b89190c72e2f369- Reuse basis
- All rights reserved, per the copyright page. Public text is cite_only: the copyright page says all rights reserved, so the terms do not clearly allow quotation (your WHO decision on issue 2 covers the CC BY-NC-SA guidelines). Easy to change to quote if you decide otherwise. Hash only; the PDF is not committed.
-
Background Guideline: Sodium intake for adults and children
- Locator
- Annex 8, Quality of evidence, page 37
- How it applies
- WHO's summary of evidence quality when it set the strength of the recommendation.
- Retrieved
- Source effective date
- Not reported
- Source state
- Current
- Snapshot hash
1f42c807c29ae255b31554afafaed683d5598414a1e5cc2a4b89190c72e2f369- Reuse basis
- All rights reserved, per the copyright page. Public text is cite_only: the copyright page says all rights reserved, so the terms do not clearly allow quotation (your WHO decision on issue 2 covers the CC BY-NC-SA guidelines). Easy to change to quote if you decide otherwise. Hash only; the PDF is not committed.
Clinical links
Each link reports what one cited claim says about one population. "Evaluated for" means studied, not shown to work. These links do not show that anything is effective or right for you.
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Claim, not a settled fact Observational association with stroke (WHO 2012, quality very low to low): Stroke
Applies to Adult- Adults in the general population, with or without hypertension. The 2012 text also applies the recommendation to pregnant and lactating women; that item belongs to the maternal atlas and is outside this context. The 2012 text excludes people with illnesses or medicines that can cause low blood sodium or sudden fluid retention, and people who need physician-supervised diets, such as people with heart failure or type 1 diabetes.
- Not stated as a care setting. The guidance covers everyday dietary sodium intake.
- Global guidance. The cohort studies in the 2012 meta-analysis were conducted in Europe, Japan and the United States.
- Adult; the sources set no age bounds in the passages read
The WHO 2012 sodium guideline reports that, in cohort studies of adults, people who ate more sodium had more strokes than people who ate the least. The pooled risk ratio was 1.24 (95% CI 1.08 to 1.43) for stroke and 1.63 (95% CI 1.27 to 2.10) for fatal stroke. WHO rated the evidence very low quality for stroke and low quality for fatal stroke. These are observational comparisons of higher and lower intake groups.Limitations. Observational cohort data with very low to low quality ratings from WHO. Groups were compared on sodium intake, not on a change in intake, and the guideline notes that some cohort studies found no link, an inverse link (higher intake with lower risk) or a J-shaped curve. Intake ranges differed widely between studies, and the lowest-intake groups in some studies ate as much as 4 g of sodium a day, so the comparison is not intake above against below the WHO limit of 2 g. Nothing here shows that cutting sodium prevents strokes; the SSaSS claim concerns a different intervention.
-
Claim, not a settled fact Recommended for this: Salt substitution (lower-sodium, potassium-containing salt)
Applies to Adult- Adults in general populations. The recommendation excludes pregnant women, children, and people with kidney impairment or other circumstances or conditions that might compromise potassium excretion.
- Not stated as a care setting. The recommendation concerns table salt that a person adds to food while cooking or eating.
- Global guideline; no country is specified
- Adult; the guideline states no age bounds and excludes children
If adults in a general population choose to use table salt, WHO suggests replacing regular table salt with a lower-sodium salt substitute that contains potassium. This is a conditional recommendation, made alongside WHO's strong recommendation to keep sodium intake below 2 g a day. It is not intended for pregnant women, children, or people with kidney impairment or other conditions that might make it harder to clear potassium.Limitations. WHO describes the evidence behind the recommendation as "moderate-to-low certainty (an assessment of low certainty overall ...)". The per-outcome levels are in WHO's Annex 6 GRADE table, which this record does not extract. It covers table salt that a person adds to food, not condiments such as soy sauce or sodium already in manufactured foods and restaurant meals. All trials in WHO's review excluded people who could be harmed by extra potassium and some also excluded people with diabetes, so evidence for those groups is uncertain. WHO says reducing sodium from all sources is the preferred strategy, and that a household member at risk of hyperkalaemia should not have food prepared with a substitute. It is recorded beside the NICE caution and does not resolve it.
Record details
- Record id
cardio:high-sodium-intake- Content hash
28d5c3f4d3562c348a41974113320d38c1cf6e4331af59a11880360bbb34e4d2