electrolyte supplements—capsules in particular–how many?

"Be careful with high-potassium formulas"

This is a good reminder. It's a case where "more is better" can collide calamitously with human physiology for some people.

"lite salt will probably be safe for most people"

True, but there are good and not so good ways to find out if it turns out you're not most people. (And all of us are not most people in at least some ways, whether we know it or not!) Ergo the wisdom of:

"people with health issues should always consult with a doctor."

Even if they don't know they have health issues! (Hmmm, but how do I know whether … unless …? Hmmm.)

"350 mg of K X perhaps 3 liters of water/day = high K?"

Well, considering that grape juice has about 600 mg/liter, 350 mg/liter doesn't sound so awful. OTOH, the guy who's drinking 10+ liters of water/day would be taking in a lot of potassium. As others have pointed out, certain conditions or medications can impair potassium excretion to the extent that the relevant people are restricted wrt consumption of certain real foods, let alone potassium chloride nearly straight up. IMO, it's really not a good idea to use it casually in quantities that would exceed normal levels of intake from a diet of real food, and even that may be more than is healthy for some people.

"sea salt (has) the same hidden problem: salts other than sodium chloride and consequently higher levels of K, Mg, etc"

Well, there's good news and bad news about that – sea salt's basically the same as regular salt from a dietary standpoint (see, e.g., http://www.mayoclinic.com/health/sea-salt/AN01142). The other minerals are present largely at trace levels. Even the sea salts with the highest potassium content only have a few % (I'll update this with hard numbers from the paper if people desire) – you'd need to eat about a tbsp of high potassium sea salt (containing > 5 *grams* of sodium) to get as much potassium as a serving of dried plums has.

And just for completeness, I've come back to dried fruit several times as a relevant comparison, but dried fruit is on the limited consumption list for people on potassium-restricted diets.

Best,

Bill S.

"OTOH, the guy who's drinking 10+ liters of water/day would be taking in a lot of potassium."

For the guy who drinks 10 liters of water a day in all but the most extreme circumstances, an excess of potassium would be the least of his troubles. Think hyponatremia? In any case, 10 X 350 mg = 3500 mg, still less than the recommended daily intake of K.

"As others have pointed out, certain conditions or medications can impair potassium excretion to the extent that the relevant people are restricted wrt consumption of certain real foods, let alone potassium chloride nearly straight up."

One would think such people would be aware enough of their situation to avoid electrolyte supplementation in any form. Why take the exception and use it to argue that most people should avoid a cheap, simple means of taking in a modest amount of sodium and potassium when exercising for an extended period? The daily intake recommendation for potassium is around 4000 mg, so 350 mg X 3 liters of water, a fairly average amount for most hikers, is hardly "straight up".

"For the guy who drinks 10 liters of water a day in all but the most extreme circumstances, an excess of potassium would be the least of his troubles. Think hyponatremia?"

Using your recommended Morton's Lite, the 3 grams of sodium (plus whatever's in his diet) should take care of that, right?

"In any case, 10 X 350 mg = 3500 mg, still less than the recommended daily intake of K"

The recommended amount for most people, but not including what's in his diet. Others' diets will differ, but quick calcs show that I take in ~ 5-8 grams/day of potassium from food when backpacking.

"One would think such people would be aware enough of their situation to avoid electrolyte supplementation in any form."

One might, but not everyone has particulary good access to medical care, and even among those who do, not all take advantage of it. In some surveys, about a third of people report that they don't regularly or ever see a doctor. People can have significant health changes and not be aware of them.

"Why take the exception and use it to argue that most people should avoid a cheap, simple means of taking in a modest amount of sodium and potassium when exercising for an extended period?"

That was not *at all* my intent. If my comments read that way, then I have expressed myself poorly. Indeed, I'd argue that most people *should* be supplementing with modest amount of sodium and potassium while exercising for extended periods if they're not getting adequate amounts already from their diets.

"The daily intake recommendation for potassium is around 4000 mg, so 350 mg X 3 liters of water, a fairly average amount for most hikers, is hardly "straight up"."

By "straight up," I refer to the supplement itself, which is nearly 50% KCl. Due to the high concentration, its potential for misuse is significantly greater than that of most other dietary potassium sources. If used as you suggest, it will cause no harm to most people. (And indeed I have used it myself that way, during conditions when I wasn't eating real food with plenty of it.)

Bill S.

Thermotabs might be a cheaper alternative to Saltstick Caps.

Thermotabs: 180 mg Sodium, 15 mg Potassium, about 10 cents each.

Saltstick Caps: 215 mg Sodium, 63 mg Potassium, 100 IU Vitamin D, and small amounts of a few other minerals, 20 cents each retail.

Vitamin D RDA is 600 IU for adults, Tolerable Upper Intake Level is 4,000 IU daily for adults (NIH).

Saltstick Caps Plus: 190 mg Sodium, 53 mg Potassium, 100 IU Vitamin D, 30 mg caffeine, and small amounts of a few other minerals, 30 cents each retail.

For comparison, a tall Starbucks coffee has 260 mg caffeine.

So if I switched to Thermotabs, I’d take about the same number as Saltstick Caps Plus. But I’d miss the caffeine :-(

— Rex

I just wanted to pop into this thread to remind everyone that Potassium and Sodium are not the only electrolytes necessary for proper muscle function. Personally, while I don't steadily dose electrolytes, I have Hammer Endurolytes in a small bag and will take one during big hill climbs (say more than 3000' of sustained elevation change), both up and down. I find that it greatly helps my recovery even while eating normal, healthy trail food.

A small supplement not intended to replace your primary source of nutrition is an easy insurance policy against feeling like hell. Worth it, in my opinion.