Researchers analyzed 34 studies involving over 37,000 people to see if salt substitutes (specially formulated salts with less sodium and more potassium) could help reduce blood pressure and prevent heart disease. The good news: these salt substitutes appear to lower blood pressure and may reduce deaths from heart problems compared to regular salt. However, most of the evidence comes from one large study in China, so scientists aren’t sure if the results apply equally to people in other countries. The substitutes seem safe and taste similar to regular salt, but people with kidney problems should avoid them.

The Quick Take

  • What they studied: Do salt substitutes (salt with less sodium and added potassium) work better than regular salt for lowering blood pressure and preventing heart disease?
  • Who participated: 37,063 adults from 15 countries (average age 62 years old) in 34 different research studies. About half the studies were from China, and half were from other countries.
  • Key finding: Salt substitutes with moderate potassium and low sodium probably lower blood pressure by about 4-5 points and may reduce deaths from heart disease by 7-17 per 1,000 people, though most of this evidence comes from one large Chinese study.
  • What it means for you: If you have high blood pressure, salt substitutes may help—but talk to your doctor first, especially if you have kidney problems. The benefits shown in studies are real, but we need more research outside of China to be completely sure they work the same way everywhere.

The Research Details

Scientists searched medical databases for all studies that compared salt substitutes to regular salt in adults. They found 34 high-quality studies (called randomized controlled trials, where people are randomly assigned to use either salt substitutes or regular salt). They combined all the results using special statistical methods to see which type of salt substitute worked best.

The researchers looked at different types of salt substitutes—some had more potassium, some had very little sodium, and some had a mix. They tracked what happened to people’s blood pressure, heart attacks, strokes, and deaths over time. They also checked if anyone had bad side effects or stopped using the salt substitutes because they didn’t like the taste.

To make sure the results were trustworthy, the researchers checked each study for quality problems and rated how confident they were in their findings using a system called GRADE (which helps separate strong evidence from weaker evidence).

This research approach is important because it combines information from many different studies, which gives us a clearer picture than looking at just one study alone. By comparing different types of salt substitutes, scientists can figure out which ones work best. This helps doctors and patients make better choices about which products to use.

This is a well-designed systematic review and meta-analysis, which is one of the strongest types of research. The researchers searched multiple databases and included studies from many countries. However, there’s an important limitation: most of the evidence for mortality benefits (preventing deaths) comes from one very large Chinese study with almost 21,000 people. When researchers removed this study, the mortality benefits disappeared. This means we can’t be sure the benefits apply to people in other countries with different diets and lifestyles. The researchers were honest about this limitation, which is a sign of good science.

What the Results Show

Salt substitutes with moderate potassium (25-40% potassium chloride) and low sodium (60-79% regular salt) showed the strongest benefits. These substitutes lowered systolic blood pressure (the top number) by about 4.4-4.6 points on average. This might not sound like much, but even small reductions in blood pressure can reduce the risk of heart attacks and strokes.

The study found that these salt substitutes probably reduced all-cause deaths by 7-17 per 1,000 people and reduced deaths from heart disease by similar amounts. They also reduced non-fatal heart attacks and strokes. The researchers rated this evidence as moderate to high quality, meaning they’re fairly confident in these results.

Salt substitutes with higher potassium or very low sodium also lowered blood pressure similarly, but the evidence for preventing deaths and heart events was less certain. This suggests that the moderate-potassium, low-sodium combination might be the sweet spot.

Importantly, no one experienced serious side effects from using salt substitutes, and people found them just as acceptable and tasty as regular salt. No one quit the studies because they didn’t like the taste.

The research showed that salt substitutes didn’t cause any increase in kidney problems or high potassium levels in the blood (which can be dangerous). This is reassuring because potassium-based salt substitutes are sometimes avoided due to safety concerns. The studies also found that people were willing to use these products long-term, suggesting they could be a practical solution for reducing salt intake.

Previous research suggested that reducing salt intake could lower blood pressure, but it wasn’t clear which type of salt substitute worked best or if they could actually prevent heart disease and death. This new analysis provides stronger evidence that salt substitutes can do more than just lower blood pressure—they may actually prevent serious health events. However, earlier research in Western countries showed smaller blood pressure benefits, which is why the researchers note that most of the mortality benefits in this analysis come from Chinese studies.

The biggest limitation is that most of the evidence for mortality benefits comes from one large Chinese study (SSaSS trial with 20,995 people). When this study is removed, the mortality benefits disappear statistically. This means we can’t be confident that salt substitutes prevent deaths in people outside of China. Additionally, none of the non-Chinese studies provided mortality data, so we’re comparing apples and oranges. The studies were mostly done in older adults (average age 62), so we don’t know if results apply to younger people. Finally, most studies were relatively short-term, so we don’t know about long-term effects over many years.

The Bottom Line

For people with high blood pressure: Salt substitutes with moderate potassium and low sodium appear to be a safe and effective way to lower blood pressure (moderate to high confidence). The blood pressure reduction is real and meaningful. For preventing heart disease and death: The evidence is promising but mainly comes from Chinese populations, so we’re less confident about benefits in other countries (moderate confidence). Before using salt substitutes: Talk to your doctor, especially if you have kidney disease, diabetes, or take medications that affect potassium levels. Your doctor should check your kidney function first.

Salt substitutes may be helpful for: Adults with high blood pressure who want to reduce salt intake, people at risk for heart disease, and older adults. Salt substitutes should be avoided by: People with kidney disease, people with high potassium levels in their blood, and people taking certain blood pressure or heart medications without doctor approval. More research is needed before recommending them universally to people outside of China.

Blood pressure reductions typically appear within weeks to a few months of using salt substitutes consistently. Heart disease and mortality benefits (if they occur) would take much longer—likely years—to become apparent. You should see some blood pressure improvement within 2-3 months if the product is going to work for you.

Want to Apply This Research?

  • Track daily salt intake by logging meals and noting when you use salt substitutes instead of regular salt. Also track home blood pressure readings weekly (same time of day) to see if your numbers improve over 4-8 weeks.
  • Set a goal to replace regular salt with a moderate-potassium, low-sodium salt substitute in your kitchen. Start by using it for cooking and at the table, and track how many days per week you successfully make the switch. Aim for 80% compliance.
  • Weekly blood pressure checks at home, monthly tracking of salt substitute usage consistency, and quarterly check-ins with your doctor to monitor kidney function and potassium levels. Log any side effects or taste preferences to help identify the best product for you.

This research summary is for educational purposes only and should not replace professional medical advice. Salt substitutes may not be appropriate for everyone, particularly those with kidney disease, high potassium levels, or taking certain medications. Before using salt substitutes, consult with your healthcare provider to ensure they’re safe for your individual health situation. The mortality benefits described in this research are primarily based on studies from China and may not apply equally to other populations. Always have your kidney function and potassium levels checked by a doctor before starting salt substitutes.