Potassium-enriched salt substitutes lowered the top number about 5 points and the bottom about 2.5 across 26 trials, and the largest trial had 14% fewer strokes, but people with kidney disease or on certain blood pressure pills shouldn't use them without a doctor's blood test plan.
A potassium salt substitute replaces part of the sodium chloride in table salt with potassium chloride. So one shake lowers the sodium you eat and raises the potassium at the same time, and in people with high blood pressure, both changes lower it. These products are often sold as low-sodium salt.
In my upcoming book it's a well-tested swap, and who must avoid it matters as much as how well it works. Too much potassium can be dangerous for the wrong person, and it's usually silent.
The book's grade: SUPPORTED (works). A potassium-enriched salt substitute is an Add next item, with the safety badge Check your meds first.
What is a potassium salt substitute?
The blend the 2025 American Heart Association guideline describes is typically about 25% to 30% potassium chloride and 65% to 75% sodium chloride (guideline). The biggest trials used blends with about 25% potassium chloride (SSaSS).
How much do salt substitutes lower blood pressure?
- Across 26 trials: a 2022 Cochrane review pooled 26 trials with about 35,000 adults. Salt substitutes lowered the top number about 4.8 points and the bottom about 2.4, with moderate certainty. Blood potassium went up slightly (Cochrane). For example, 145/90 would become about 140/88.
- The largest trial, SSaSS: 20,995 people in 600 villages in rural China. Everyone had either had a stroke or was 60 or older with high blood pressure. Half the villages got the 25% blend free for all their cooking. Over almost 5 years, the top number was about 3.3 points lower, with 14% fewer strokes, 13% fewer major heart and stroke events and 12% fewer deaths. Serious problems from high potassium were no more common than with regular salt, in a trial that screened out people at risk (SSaSS).
- Care homes: in 48 care homes for older adults in China, switching the kitchen salt lowered the top number about 7 points over 2 years. Simply giving out less salt did nothing (trial).
Those stroke and death results come from one large trial of people at high risk, and the book's grade covers blood pressure only.
Who should not use a salt substitute
Healthy kidneys usually get rid of extra potassium. Kidney disease and some medicines slow that down, and then even ordinary amounts can push blood potassium too high (NIH). Many people don't know their kidney results. Every trial in the Cochrane review left out people at risk of high potassium (Cochrane), and SSaSS excluded anyone with known serious kidney disease or on a potassium-keeping water pill or potassium supplement (SSaSS).
Ask your doctor first, and expect blood potassium checks, if you have:
- Kidney disease
- Heart failure
- Type 1 diabetes
- Addison disease or liver disease
Or if you take any of these medicines:
- ACE inhibitors (names ending in "-pril," such as lisinopril) and ARBs (names ending in "-sartan," such as losartan). That includes sacubitril-valsartan, a heart failure pill with an ARB inside (guideline).
- Spironolactone, eplerenone and finerenone.
- The water pills amiloride and triamterene.
- Aliskiren, and newer pills ending in "-drostat."
- The transplant medicines cyclosporine and tacrolimus.
- The antibiotic trimethoprim-sulfamethoxazole.
- NSAID pain pills taken regularly, and the blood thinner heparin.
Watch for combination pills. Some tablets carry one of these inside, such as triamterene or lisinopril or losartan combined with a water pill. If you're not sure what's in yours, ask your pharmacist.
Kidney disease is often silent and is found with a blood test (eGFR) and a urine test for albumin.
High potassium is often silent too. Most people find out from a routine blood test. Severe cases can cause muscle weakness, palpitations and heart rhythm problems that can be life-threatening (NIH). If you notice new muscle weakness, a racing or skipping heartbeat, or you faint, get medical care right away.
If you're in one of these groups, my answer on salt substitutes is "not without a blood test plan." Herbs, spices and lemon are a safer way to cut salt.
Why it isn't a Start here item
In the SSaSS villages, most salt went in at the stove. In one U.S. study, the shaker and the stove together added only about a tenth of people's sodium, and about 71% was added in factories and restaurants (study). A salt substitute can only replace the salt you add yourself. The guideline says these products help most when your salt is added at home, and that the tested blends can be hard to find in the U.S. (guideline).
So a salt substitute fits best if you cook at home and salt at the stove, with normal kidney tests and no potassium-holding pills.
Best salt substitute for high blood pressure: what to look for
What U.S. stores carry often isn't the tested blend.
- "Lite" salts. A widely sold lite salt is equal parts sodium chloride and potassium chloride. That's about twice the potassium share of the 25% blends in the trials.
- "Salt-free" substitutes. Many are almost entirely potassium chloride. I couldn't find a blood pressure trial of the pure potassium kind, so the book grades them NO EVIDENCE (not tested properly) and a Skip. They can also carry far more potassium than a blend. If you use a substitute, choose a blend.
- Sea, pink and kosher salt. These are about as salty as table salt, gram for gram. Switching is graded UNLIKELY TO HELP.
Across products, a teaspoon can carry anywhere from about 440 to 2,800 mg of potassium (NIH). Read the ingredient list to see whether potassium chloride is listed and how much of the mix it is, then check the potassium line. If yours has more potassium chloride than the tested blends, a lighter hand keeps you closer to what the trials used. If you're in a risk group above, ask first whatever the blend.
Some reduced-sodium foods also use potassium chloride in place of salt. That potassium counts too, so check the ingredient list if your doctor has told you to limit potassium.
A low-salt diet for hypertension comes first
A salt substitute is an add-on. The bigger win for most Americans is cutting the sodium in packaged and restaurant food, which the book grades SUPPORTED and lists as Start here.
In a review of 34 trials, people who cut about 1,700 mg of sodium a day, about 3/4 teaspoon of salt, lowered the top number about 5 points and the bottom about 3 (review). Every 1,000 mg less a day lowered the top number about 2.4 points (review).
How I'd start:
- Find where you are. Add up the sodium on your labels for three ordinary days, or use the U.S. average of about 3,400 mg a day as a fair guess (FDA).
- Cut about 1,000 mg a day first. That's my number, based on the 2.4 points per 1,000 mg.
- Go after packaged and restaurant food, then sauces and seasoning packets, and the shaker last. On a label, 5% Daily Value or less is low in sodium, and 20% or more is high.
- Get under 2,300 mg a day, then work toward 1,500 once that feels normal.
- Give it a month. The full effect of a salt cut takes several weeks to show (review).
Food may taste bland for a week or two, but your taste for salt adjusts. On blood pressure pills, watch for dizziness when you stand. If you take lithium, check with your doctor before a big salt cut.
Bottom line
A potassium-enriched salt substitute lowered the top number about 5 points in 26 trials, and in the largest trial it came with 14% fewer strokes. It helps most if you cook and salt at home. Choose a blend close to the tested 25% potassium chloride, not a pure potassium product. If you have kidney disease or heart failure, or take an ACE inhibitor, an ARB, spironolactone or another potassium-holding pill, don't start one until your doctor says yes and checks your blood. For most people with hypertension, a low-salt diet comes first, and the substitute is an add-on.
Questions people ask
Is salt substitute safe for high blood pressure?
For someone with normal kidney tests who takes no potassium-holding medicines, a tested blend makes sense, and blends lowered blood pressure in 26 trials. Very large amounts can push potassium too high even in healthy people. If you don't know your kidney results, or you take one of the medicines above, ask first, because potassium can build up without symptoms.
Can I use a salt substitute if I take lisinopril?
Ask your doctor first. Lisinopril is an ACE inhibitor, one of the medicines that make your body hold on to potassium. Your doctor may say yes with a blood test plan, or may steer you to herbs and spices instead.
What is the best salt substitute for high blood pressure?
The tested kind is a blend of about 25% to 30% potassium chloride with the rest sodium chloride. A widely sold U.S. "lite" salt has about twice that share of potassium, so use less of it. I couldn't find a blood pressure trial of pure potassium chloride products.
Is sea salt or pink salt better for blood pressure?
No. They're about as salty as table salt, gram for gram. In a small trial of 17 women with high blood pressure, Himalayan salt and table salt gave the same blood pressure (trial). The book grades switching UNLIKELY TO HELP.
More of the kitchen, graded
The salt substitute is one of dozens of items graded in Your Blood Pressure by the Numbers, coming soon. The book also grades potassium-rich foods (SUPPORTED, Start here), store-bought potassium pills (NO EVIDENCE at their 99 mg dose) and herbs and spices in place of salt (PLAUSIBLE, might help), with the numbers behind each. For now, see the DASH diet for high blood pressure and how to lower blood pressure naturally.