Healthy kidneys are necessary to excrete potassium. If you’re not sure if you’re at risk, ask your doctor about having your kidney function tested.
Based on our findings, high potassium intakes probably far exceed current and even recommended intakes. The problem is that we’ve replaced many of the potassium-rich plant foods that used to fill our diets—fruits, vegetables, leafy greens, roots, tubers—with heavy, calorie-dense fat and added sugars, and stripped of not only fiber but potassium.
In a traditional diet, especially plant-based, potassium intake is high and sodium intake is low. But now, high blood pressure is the second leading cause of death worldwide, killing more than 10 million people each year. Only unhealthy diets rank high among the global risk factors for death, as you can see below and at 0:41 in my video. Potassium Chloride Salt Substitute Side Effects.
We can improve both by eating whole, healthy plant foods like greens and beans, which are full of potassium and help lower blood pressure. But since most of us get too much sodium and too little potassium, what about using salt substitutes? Potassium chloride is a common substitute for salt, so you’ll be substituting sodium for potassium.
And it works. Based on a meta-analysis of more than a dozen randomized controlled trials, substituting sodium chloride for potassium chloride lowers blood pressure. Most experiments involved replacing common salt with less than 30% potassium chloride, and they still got results. And with less than 30% potassium chloride, most people can’t even tell the difference between common salt and potassium salt. So, can it taste the same but still lower blood pressure? What is the catch?
Potassium chloride is “generally recognized as safe” (GRAS) by the US Food and Drug Administration. The only major concern for healthy people is that if you are 100% sodium free and only use potassium chloride salt supplements, you may find it tastes funny, adding a bitter or metallic taste. I’ve found that it depends on what I’m saving. Potassium chloride works very well in some dishes and snacks, but I find it makes other foods inedible. When I learned about the science of sodium and ditched my salt shaker completely, within a few weeks, my palate completely changed. Everything was delicious without the salt—except the pesto. For some reason, the pesto without salt didn’t have the same flavor that I liked. So, I tried the potassium chloride salt substitute, and it worked well. I couldn’t tell the difference at all! So, I had the best of both worlds. Then I remembered that, when I was a child, I used to sprinkle salt on a small watermelon like they do in the South to make it even sweeter. I tried it with potassium salt and I almost gagged. Salt area is not everything.
The reason healthy people don’t worry about getting too much potassium is that they just urinate more, because of the kidneys. But that’s potassium in food—what about supplements? No side effects have been shown with long-term potassium supplementation in doses up to 3,000 mg per day. In fact, blood levels of potassium are maintained in the normal range by healthy kidneys even when potassium intake is increased to about 15,000 mg per day. That’s not surprising since we started eating so many plant foods rich in potassium that the natural potassium intake for the human species may be on the order of 15,000 mg per day.
Basically, the normal range of potassium levels in the blood is between 3.5 and 5.0 mmol/L; It starts to rise as high as 6 mmol/L. But give people potassium supplements—like the salt replacement trial where participants got an average of about 2,000 milligrams a day—and blood levels rise only 0.14 mmol/L. Therefore, they may range from 4 to 4.14 mmol/L, not something that will push the levels into the dangerous range.
Now, there is a limit. A person with a “banana habit” can lower their potassium from the normal level to more than 6 mmol/L, but this special condition was the result of eating as little as 20 bananas a day for many years. Eating 10 kilos of carrots every day is also not a good idea. That’s like 75 carrots in one day—which is actually possible with a juicer, which is what one person tried as part of a prostate cancer treatment. What about excessive salt intake?
A report in the 1940s focused on lithium poisoning from the use of salt fields. Why? Because lithium chloride was used instead of salt. Yes! But what about potassium chloride, which is used today? There is one case where someone killed himself by taking a little more than a tablespoon of potassium chloride instead of salt. That doesn’t seem like much—just a tablespoon? I mean, how can we keep that on the shelves if just a spoonful is going to kill you? However, even a small amount of common salt, if taken at once, can kill you too. In fact, swallowing salt water was apparently a common form of suicide in ancient China.
Having said all that, a small number of people may have problems, especially people with severe renal impairment. That’s why there has been so much reluctance to push potassium-based salt substitutes at the population level. If your kidneys can’t handle potassium, then it can be a big problem. We are talking about people with known kidney disease, diabetes (since diabetes can lead to kidney damage), congestive heart failure, those taking medications that inhibit potassium excretion, older adults, and people with adrenal insufficiency. If you’re not sure if you’re at risk, ask your doctor about having your kidney function tested.
Ironically, potassium is so good at reducing death from high blood pressure—even among those with kidney disease—that using potassium chloride instead of salt would likely save many lives despite the risk, as you can see below and at 5:45 in mine. video.
Traditional dietary recommendations for kidney patients limited the consumption of fruits and vegetables because they are high in potassium. However, this view is quickly changing given the many benefits of a plant-based diet. A whole, plant-based diet may even improve chronic kidney disease. For example, there is growing evidence that a whole-food, plant-based diet may help slow the progression of chronic kidney disease and delay kidney failure. Therefore, the practice of restricting potassium intake in kidney patients should really be reserved for patients with documented hyperkalemia, a potassium level of 6 or more, because the key to stopping the progression of chronic kidney disease may lie in the production area.
Doctor’s Note
If you are in trouble, you can call the National Suicide Prevention Lifeline 24 hours a day, seven days a week, at 800-273-8255.
This is the last blog in a three-part series. If you missed the first two, check it out Mineral Intake Recommendations Only 1 in 6,000 US Adults Meet again Are Potassium Chloride Salt Substitutes Worth Trying?.
