Sodium (salt) reduction
Last reviewed 25 August 2026 · Evidence-graded review — see Methodology
Salt drives up blood pressure, and blood pressure drives heart attacks and strokes. Most sodium comes from packaged and restaurant food, so you can overshoot badly without ever touching the shaker. Cutting back works within weeks and costs nothing.
The hardest evidence is a randomised trial of about 21,000 older adults in rural China in which replacing ordinary salt with a potassium-enriched substitute cut strokes by 14 percent and premature deaths by 12 percent (Neal et al., NEJM 2021). Systematic reviews for the BMJ reached the same direction from the other side, finding lower sodium intake reduces blood pressure across adult populations and is associated with fewer fatal and non-fatal strokes (Aburto et al., 2013). The World Health Organization advises staying under 2 g of sodium a day, about one teaspoon of salt from all sources combined. This grades strong because a hard-outcome trial, many blood-pressure trials and large cohorts all point one way. One caveat belongs in the open: potassium-based substitutes suit most people but need a doctor's sign-off if you have kidney disease or take potassium-sparing medication.
Doing it: Keep under 2,000 mg sodium a day from everything you eat. Read labels, cook more at home, season with herbs, pepper and acid instead of salt, and ask your doctor before switching to potassium salt substitutes.
Who it suits: Everyone, and most of all people with raised blood pressure; the potassium-substitute caveat applies if you have kidney disease or relevant medications
Sources
- Neal B, et al. Effect of Salt Substitution on Cardiovascular Events and Death. N Engl J Med 2021.
- Aburto NJ, et al. Effect of lower sodium intake on health: systematic review and meta-analyses. BMJ 2013.
- World Health Organization, Sodium reduction fact sheet.
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