The Study
The role of body mass index in the association between dietary sodium intake and blood pressure: A mediation analysis with NHANES.
This study looked at data from lots of people and found that those who ate more salt tended to have higher blood pressure and higher body weight. But it didn’t change anyone’s diet or weight to see what would happen—it just noticed patterns. So we can’t say salt causes high blood pressure, only that they often happen together.
Analysis score
Maximum 44 for a cross-sectional study.
Where the score came from
Eating more salt doesn't just raise blood pressure directly—it also makes people gain weight, and that extra weight raises blood pressure too.
Where does this study sit?
Reviews of RCTs (Meta-analyses)
Max 100Randomized Trials
Max 90Reviews of Cohort Studies
Max 85Cohort Studies
Max 72Reviews of Case-Control Studies
Max 63Case-Control Studies
Max 58Cross-Sectional & Case Series
Max 50Expert Opinion
Max 544 / 100
Quality score
Snapshots of a population at a single point in time, or descriptions of small groups. Can identify correlations and prevalence, but cannot determine cause and effect.
Key takeaways
Summary
Based on the study abstract and findings.
- 1This is a small but measurable increase—like the difference between standing and sitting—but it adds up across millions of people and can increase heart disease risk over time.
- 2For every extra gram of salt eaten per day, blood pressure goes up by 0.36 mmHg.
- 30.14 mmHg is from salt directly, and 0.23 mmHg is from salt causing weight gain.
Score breakdown, methodology, conflicts of interest, evidence analysis & raw study data
Publication
Journal
Nutrition, metabolism, and cardiovascular diseases : NMCD
Year
2021
Authors
Q. Feng, Zuyao Yang, M. May, K. Tsoi, Suzanne M Ingle, Eric K. P. Lee, S. Y. Wong, J. Kim
Related Content
Claims (4)
Consuming large amounts of sodium leads to higher blood pressure in adults.
In U.S. adults aged 60 and younger, higher body weight increases the extent to which sodium intake raises blood pressure.
For U.S. adults without high blood pressure or preexisting disease, consuming 1 gram more sodium per day is linked to a 0.23 mmHg rise in systolic blood pressure, and this effect is explained by changes in body mass index, even when accounting for other lifestyle and dietary factors.
For every additional gram of sodium consumed daily, systolic blood pressure rises by 0.36 mmHg in U.S. adults aged 20 and older without hypertension or baseline disease, with 0.14 mmHg of this rise occurring directly and 0.23 mmHg linked to increased body mass index.
Not medical advice. For informational purposes only. Always consult a qualified healthcare professional before making health decisions.