Expert: Ronald Levy, M.D. - 7/29/2008

Question
Hello Dr. Levy,

I have been studying a bit, on the internet that is, concerning sodium/potassium imbalance as I would like to intake more potassium and less sodium.

I discovered an article on Dr. Passwater.com where Dr. Passwater was interviewing Dr. Richard Moore. Below is an excerpt from that article:

"Moore: Let me give you a very interesting statistic. In 1985, The New England Journal of Medicine published an article titled "Paleolithic Nutrition." The authors, who had credentials as anthropologists specializing in the Paleolithic era, determined that, on average, our caveman forebears got around 11,000 mg of potassium daily and about 700 mg of sodium. This, by the way, is about the same ratio that modern-day hunter / gatherers have. It works out to a dietary K Factor of 15.7."
"Today, in the United States, that 11,000 mg has shrunk to 2,500 mg of potassium."

I also read where the avg. present day intake of sodium I believe has increased to between 3000 and 4500 mgs.

I have also read in other articles on the net where we should be getting at least 4500 mgs. of  potassium/day.

I've also read where one cannot purchase a potassium pill supplement above 99 mgs. per tablet. I asked the pharmacist at Wal-Mart tonight why this is so. He stated that potassium is good but in higher limits can affect heart contraction and one needs to consult their physician. Could it be possible though, that our ancient ancestors were actually ingesting a normal value of potassium at 11,000 mgs./day but some may have suffered heart problems at these seemingly higher levels?

If, in fact, our paleolithic ancestors were getting as high as 11,000 mgs. of potassium daily, then shouldn't we in the present day be ingesting the equivalent amount since, as Dr. Moore asserts, we are still genetically predisposed to metabolizing nutrients/foods in much the same way as our ancient ancestors?

I'll go with what the doctors advise. That brings up one more question. How would one safely and correctly determine the correct amount of potassium that each individual needs without under or overdoing it? Is this value given in the blood work of a normal routine physical exam or does this necessitate a more expensive and elaborate testing procedure?

Thank you for taking the time and concern to review my issue and I look forward to hearing your professional reply.

Sincerely,

Mike E.


Answer
You should NOT increase your Potassium level except under direct supervision of a physician. Potassium, in high doses, can cause your heart to arrest. It is this durg (in fact) that is given during lethal injections to execute prisoners. Your body will naturally balance out the potassium (and sodium) you intake through your kidneys. If you take increased doses, the kidney will just flush them out. But if you take a large concentration of Potassium, the kidneys cannot work fast enough to excrete it and since Potassium is an important part of muscle contraction, it will cause your heart to fibrillate.I don't know what ancient man ate (nor do I care), our bodies are designed to equilibrate the ions we take in so feel free to eat another banana but don't try to take Potassium supplements..

Ronald Levy, MD
Associate Professor of Anesthesiology
UTMB-Galveston