Cutting salt from your diet can be a loathsome idea for some, mainly for fear of losing out on flavor. Fortunately, for those of us that enjoy that brackish briny kick, there are many salt substitutes out there. The question is…are they good for you?
What's the issue? Salt is a major source of dietary sodium (1;2), and consuming too much sodium increases the risk of stroke, heart disease, and in particular, high blood pressure (2-5;6). Affecting more than 4.5 million Canadians (7), high blood pressure is known as ‘the silent killer’ because it often develops without symptoms. When left uncontrolled, it can lead to heart attacks, heart failure, aneurysms, and metabolic syndrome (6). This is why sodium reduction is now recognized as an important way to prevent major chronic diseases (8;9).
Sodium isn’t all bad. In fact, it's absolutely necessary for the body to function (1). According to Canadian guidelines, older adults 51-70 years old should consume 1300 mg of sodium daily, and older adults over 70 should consume 1200 mg (10). This amounts to roughly one-quarter of a teaspoon. The problem is that many of us consume far too much sodium (2)—often more than double the recommended amount (2;11;12)!
To cut down on sodium, some people are turning to the plentiful supply of low-sodium salt substitutes. These substitutes are made with less sodium and more of another mineral—most often potassium. But with salt substitutes being so readily available, should we be reaching to place them in our grocery carts?
What the research tells us
A recent systematic review compared the use of low-sodium salt substitutes to normal salt. The review found that these salt substitutes may lower systolic and diastolic blood pressure, both in people with normal and high blood pressure. Interestingly, the salt substitutes didn’t appear to lower the risk of new or existing hypertension or death.
These findings are different from most other research, which has found that low-sodium salt substitutes have the most noticeable effect in people with high blood pressure. Why the difference? Some of the studies that looked at people with regular blood pressure in the more recent review were of poor quality, didn’t assess many people, and/or included people who were not representative of the general population. Therefore, currently, the authors only recommend low-sodium salt substitutes in people with high blood pressure. Overall, more research is needed to improve the evidence-base around low-sodium salt-substitutes (8).
Despite their potential benefits, salt substitutes are not safe for everyone. Stomach issues, respiratory symptoms, and heart trouble are potential, albeit very rare, side effects that have been documented (1). Also, people who have difficultly eliminating potassium from their body—such as people who have kidney disease or are on potassium-sparing drugs—should speak with their health care provider before using salt substitutes. This is because salt substitutes that are high in potassium can cause a dangerous build-up of potassium in the body (13-14).
So, should you ‘pass the salt-substitute’ or ‘pass on the salt-substitute’? Well, low-sodium salt substitutes are a readily-available option to help lower your sodium intake, and may even help reduce your blood pressure. But they may not be right for everyone. Before trading in salt for a salt substitute, make sure to speak with your health care provider. Some initial questions to ask include: 1) are salt substitutes a good option for me, 2) are there certain types of salt-substitutes that I should favour or avoid, and 3) are there instructions on how I should be using salt-substitutes? Don’t forget to read the ingredient list of any salt-substitute you want to use so you can assess how it can impact your health!