High sodium intake is a major cause of high blood pressure and heart disease. Scientists reviewed research on salt substitutes that replace regular salt with potassium and magnesium compounds. They found that certain types of potassium and magnesium salts are absorbed well by the body and could be good alternatives to regular salt. However, some forms—like magnesium oxide—don’t work as well because the body has trouble absorbing them. This research helps identify which salt substitutes are actually effective at getting these beneficial minerals into your system.

The Quick Take

  • What they studied: Whether different types of potassium and magnesium salts can be good replacements for regular table salt, and how well the body absorbs them
  • Who participated: This was a review of multiple studies that included healthy adults. The researchers looked at studies testing different salt substitutes to see which ones the body could actually use effectively
  • Key finding: Potassium chloride, potassium citrate, magnesium citrate, and magnesium chloride all work well as salt substitutes because the body absorbs them effectively. However, magnesium oxide doesn’t work as well because it doesn’t dissolve easily in water and the body can’t absorb it efficiently
  • What it means for you: If you’re trying to reduce sodium intake for blood pressure control, look for salt substitutes containing potassium chloride, potassium citrate, magnesium citrate, or magnesium chloride. Avoid products with magnesium oxide as the main ingredient. Always talk to your doctor before using salt substitutes, especially if you have kidney problems or take certain medications

The Research Details

This was a systematic review, meaning researchers searched through scientific databases to find all the best studies on this topic. They specifically looked for randomized controlled trials—the gold standard of research—where healthy adults were given different types of potassium and magnesium salts, and scientists measured how much of these minerals the body actually absorbed and used.

The researchers used a structured search method called PICO (Population, Intervention, Comparison, Outcome) to make sure they found all relevant studies. They focused on studies that measured bioavailability, which is a fancy way of saying ‘how much of the mineral actually gets into your bloodstream and can be used by your body.’ This is important because just eating something doesn’t mean your body can use it effectively.

By reviewing multiple high-quality studies together, the researchers could see patterns about which salt substitutes work best. This approach is stronger than looking at just one study because it shows what the overall evidence suggests.

Understanding bioavailability is crucial because not all salt substitutes are created equal. Two products might look the same on a label, but if your body can’t absorb one of them well, it won’t help you get the health benefits. This review helps consumers and doctors choose salt substitutes that actually work, rather than wasting money on products that your body can’t use effectively. It’s especially important for people trying to lower their blood pressure through diet.

This is a systematic review, which is a strong type of research because it combines evidence from multiple studies. The researchers used a structured method to search for and evaluate studies, which reduces bias. However, the review only included randomized controlled trials in healthy adults, so the results might not apply perfectly to people with certain health conditions. The review was published in a peer-reviewed nutrition journal, meaning other experts checked the work before publication.

What the Results Show

The research identified four salt substitutes that work well for the body: potassium chloride, potassium citrate, magnesium citrate, and magnesium chloride. All of these are absorbed effectively by the body, whether you take them as supplements or get them from food sources, and regardless of the dose amount.

Magnesium oxide, however, performed poorly. The main reason is that it doesn’t dissolve well in water. Since your digestive system is mostly water-based, magnesium oxide can’t break down and be absorbed the way other forms can. It’s like trying to dissolve sugar in ice—it just doesn’t work well.

These findings suggest that potassium chloride and potassium citrate are excellent choices for salt substitutes because they’re well-absorbed and can help you reduce sodium while increasing potassium intake. Similarly, magnesium citrate and magnesium chloride are good options for getting more magnesium while cutting back on regular salt.

The review also noted that the form of the mineral matters significantly. Different chemical compounds of the same mineral can have very different absorption rates. This is important because manufacturers have choices about which form to use in their products. The research suggests that companies should prioritize the forms that the body can actually use, rather than choosing based on cost or other factors.

This research builds on decades of nutrition science showing that high sodium intake raises blood pressure. Previous studies have shown that potassium and magnesium help lower blood pressure, but there was less clarity about which specific salt substitutes actually deliver these minerals effectively. This review fills that gap by systematically evaluating the evidence on bioavailability, helping to confirm which products are likely to work as intended.

This review only looked at studies in healthy adults, so we don’t know for certain how these salt substitutes work in people with kidney disease, heart disease, or other conditions. Some people shouldn’t use potassium-based salt substitutes because of their health conditions, so this research doesn’t apply to everyone. Additionally, the review focused on bioavailability in controlled research settings, which might differ slightly from real-world use. The review also didn’t evaluate the taste or practical usability of these salt substitutes, which matters for whether people will actually use them.

The Bottom Line

If you want to use salt substitutes to reduce sodium intake: Choose products containing potassium chloride, potassium citrate, magnesium citrate, or magnesium chloride (Confidence: High based on absorption research). Avoid products listing magnesium oxide as the primary ingredient (Confidence: High). Always consult your doctor before using salt substitutes, especially if you have kidney problems, heart disease, or take medications that affect potassium levels (Confidence: High—this is essential medical advice).

People with high blood pressure or those trying to prevent it should pay attention to this research. Anyone looking to reduce sodium intake can benefit from choosing effective salt substitutes. However, people with kidney disease, certain heart conditions, or those taking specific medications should NOT use potassium-based salt substitutes without doctor approval. Pregnant women and people taking ACE inhibitors or potassium-sparing diuretics should also check with their healthcare provider first.

Blood pressure changes from dietary sodium reduction typically take 2-4 weeks to become noticeable, though some people see changes within days. The minerals need to be absorbed and incorporated into your body’s systems, which takes time. For best results, use salt substitutes consistently as part of an overall healthy diet. Don’t expect immediate results, but stick with it for at least a month to see if it helps your blood pressure.

Want to Apply This Research?

  • Track daily sodium intake (target: under 2,300mg) and note which salt substitute brands you’re using. Record blood pressure readings weekly at the same time of day to monitor changes over 4-8 weeks
  • Replace your regular table salt with a salt substitute containing potassium chloride or magnesium citrate. Start by using it in cooking and at the table. Set a weekly reminder to check product labels when buying processed foods to identify hidden sodium sources
  • Log salt substitute usage daily, track blood pressure weekly, and note any side effects (like digestive changes). After 4 weeks, compare your average blood pressure to baseline. Continue tracking to ensure consistency and identify which brands work best for you

This review discusses research on salt substitutes and their absorption by the body. However, salt substitutes are not appropriate for everyone. Before using any salt substitute, especially potassium-based products, consult with your healthcare provider. This is particularly important if you have kidney disease, heart disease, diabetes, or take medications that affect potassium or sodium levels. This information is for educational purposes and should not replace professional medical advice. Individual results may vary, and what works for one person may not work for another.