Salt substitutes may reduce stroke risk and lower healthcare costs
Key points to remember
- Salt substitutes may help reduce the risk of stroke and heart attack when used in place of table salt for certain populations.
- New research suggests that salt substitutes are also more cost-effective because they reduce hospitalization costs.
- However, if you are already taking blood pressure medication, adding excess potassium to your diet through a salt substitute can be risky.
Reducing salt intake can help both your heart and your wallet.
Replacing table salt with a high-potassium salt substitute could reduce the risk of stroke by 14% and the combined risk of stroke and heart attack by 13%, according to a five-year study from China. Substitution can also end up saving health care costs in the long run.
For the study, the researchers recruited more than 20,000 participants living in 600 rural villages. All participants were aged 60 or older and had high blood pressure. They were divided into a salt substitute intervention group and a table salt control group.
What is a salt substitute?
Salt substitute is more commonly referred to as low-sodium or sodium-free salt. It replaces some of the sodium chloride in common salt with potassium chloride, and has been shown to lower blood pressure.
The salt substitute intervention group received 20 grams of salt substitute daily to use in place of table salt for cooking, while the control group was encouraged to continue using regular salt.
“Salt substitution was cost-effective, an extremely rare finding,” Thomas Lung, PhD, MSc, senior researcher at the George Institute for Global Health and lead author of the study, told Verywell. “I’ve been doing cost-benefit studies for over 10 years now and I’ve never seen such clear-cut cost reduction results as these.”
Lung said the affordable salt substitute intervention reduced hospitalization costs and improved participants’ quality of life.
Salt Substitutes Explained
Table salt is a chemical compound called sodium chloride. Caroline Susie, RDN, LD, registered dietitian and spokesperson for the Academy of Nutrition and Dietetics, said sodium is an essential mineral. It helps regulate fluid balance, nerve impulses and muscle function.
While sodium is essential, excessive sodium intake draws water into the blood vessels, which increases pressure and can damage the vessels.
“It can strain your heart because your heart has to work harder to pump blood. So that’s something we need, but we want to be aware of that,” Susie said.
The American Heart Association (AHA) currently recommends that adults limit their sodium intake to 2,300 mg per day, with the goal of further reducing it to less than 1,500 mg per day. Based on this standard, 1 teaspoon of table salt contains slightly more than 2,300 mg of sodium, enough to exceed the daily limit.
Since consuming too much sodium can lead to high blood pressure and heart attacks, some people turn to salt substitutes instead.
The salt substitute used in the study contained 75% sodium chloride and 25% potassium chloride by mass, which was the standard salt substitute used in China. However, many commercial salt substitutes available in the United States completely replace sodium with potassium. For example, Morton Salt Substitute contains 0 mg of sodium and 610 mg of potassium.
Balance sodium and potassium intake
Like sodium, potassium is an essential mineral for the functioning of the body. Potassium plays many roles, including supporting heart health and lowering blood pressure.
However, too much potassium can lead to health problems, especially for people with kidney, liver or heart disease. Potassium chloride may interfere with certain medications, such as ACE inhibitors, a type of medication that lowers blood pressure, and potassium-sparing diuretics.
Eligible participants were excluded from the study if they had kidney disease, were taking potassium-sparing diuretics, or were taking potassium supplements.
“When potassium is too high, the heart does not beat properly and the individual may actually go into cardiac arrest. Unfortunately, you usually don’t know the potassium is too high until there is a problem. Sharon Puello, MA, RD, CDN, registered dietitian at FRESH Nutrition, told Verywell.
Puello said new research suggests an imbalance of sodium and potassium may be associated with a higher risk of heart disease. However, it is easier to recommend reducing sodium intake than to ask an entire population to eat enough potassium-rich fruits and vegetables, she added.
Limitations and Implications of the Salt Substitute Study
The salt substitute study had a large sample size, but all of the participants live in rural China and cook most of their meals at home. The majority of their sodium intake came from seasonings and canned foods.
In contrast, Americans get more than 70% of their sodium from “packaged, prepared, and restaurant foods,” according to the AHA. Only about 11% of the sodium in the average American diet comes from seasoning foods during cooking or at the table.
While the results of this study aren’t applicable to all populations, Lung said, they still show that low-cost preventative measures can help lower blood pressure levels.
What this means for you
If you want to reduce your sodium intake, you can focus on limiting processed and packaged foods. Herbs and spices can also be used to flavor foods instead of salt. Speak to your health care provider before replacing your table salt with a potassium chloride salt substitute, especially if you are taking certain blood pressure medications.