Potassium is essential for every cell in our bodies to function. It is mostly found in foods that have a sizable amount of carbohydrate like tubers, fruits, and vegetables. Even though it is found in leafy greens, which have a low carbohydrate content, you'd have to eat quite a bit of them to fulfill your potassium RDA. There's also talk that the RDA is too low even. So my question is: Do any VLCers routinely get enough potassium? What does a VLC day with suffficient potassium look like? And if you're on VLC and you don't get enough potassium, are you worried about it?
This question stems from my own inability to reach the potassium RDA without at least 100g carbs or so. I got 100% potassium in cronometer with only 75g carbs, but thats using 2 avocados. I'm also not sure I could eat that many vegetables, especially day after day.
PaleoHacker Ambimorph introduced me to dulse, which I've since used as a replacement for the seaweed snack packs I used to eat. As a virtual zero-carber (all meat with some herbs and spices, very occasional nuts, and seaweed), I won't be horking down tons of chard or spinach. The dulse is pretty tasty, and it's so packed with potassium that I feel a little goes a long way.
But honestly, until the dulse came along, I didn't worry about it. I had night leg cramps once in a while, especially during the weight loss phase, but potassium supps didn't do diddly for those so I stopped taking them. Otherwise, my health has done nothing but improve since I started eating this way, so I don't pay too much attention to RDAs and whatnot.
EDIT: I've been reading Phinney and Volek's new book, The Art and Science of Low-Carbohydrate Living, and here's a passage from Chapter 13 that directly addresses this question:
Early on in the VLCD era, hypokalemia (low blood potassium) was not uncommon, but once we learned to supply a modicum of sodium to avoid aldosterone-induced potassium wasting, this became a rare finding (limited usually to individuals with the concurrent use of diuretics). However, persistent hypokalemia unresponsive to sodium and potassium replacement can be a sign of underlying magnesium depletion.
Phinney and Volek spend a bit of time discussing the uses of sodium in a VLC diet; in their view, sodium is necessary to avoid mineral depletion while VLC, because restricting carbohydrates has a strong diuretic effect (Mike Eades also talks about this in his recent post on adapting to LC).
My hunch is that this is similar to the difficulty we have in getting enough vitamin E.
Meaning this: vitamin E is important as a fat-soluble antioxidant, but we don't have as much rancid fat in our bodies as SAD eaters. So reaching the vitamin E RDA might be hard, but we probably shouldn't care because the RDA doesn't apply to us.
Similarly, we have a smaller intake of sodium than the general populace, and maybe getting a ton of potassium isn't as important for us because of that.
After entering everything I eat into FitDay, it tells me that I am low in potassium, magnesium, manganese, vitamin E, calcium, and fiber. By "low" I mean like 30-45% of RDA. I found this kind of disturbing, and am looking at ways to get this back in line. I would really rather not take a handful of supplements every day, so am looking to adjust my diet.
I am also pretty high in vitamins A and B, especially when I eat liver.
I want to keep nuts moderate in my diet, but almonds are high in almost all of these things, and so I want to get almonds, meal or butter into my diet.
I looked into eating freshly ground flax seeds (I figure I could put them in yogurt or something), which also have a bunch of these nutrients. But the reports are mixed on flax seeds, Mark Sisson says they have been linked to prostrate problems. As a 41 y.o. male, that is a bit of a turn-off.
The obvious answer is to just eat a wider variety of vegetables and fruits, you can have a lot of certain types without boosting carbs much. Since I am high in vitamins A and B, I could cut out some of the meats and replace them with vegetables and butter. This might sound kind of anti-Paleo, but this is what the RDA nutrient profile requires...
Following up Kamal's suggestion that people eating a paleo diet may need less potassium than the RDA for those on the SAD, Nephropal suggests a mechanism:
SGK1 increases sodium reabsorption and potassium excretion in the kidneys. Moreover, SGK1 is influenced by insulin.... Considering that the Paleolithic sodium to potassium ratio was 1:16, then sodium was a much more crucial electrolyte to conserve... In the hospital setting, sugar in the form of dextrose and insulin are a quick way to lower serum potassium levels.
So people on paleo (or more specifically, low carb paleo) may well have lower potassium needs. On the other hand, I have heard that a ketogenic diet leads to higher excretion of salt, but I'm not sure what the excretion of sodium relative to potassium is.
Ah, here we see a strange phenomenon that I have noticed on the internet. We know we need potassium. We know that it is used by every cell in the human body. And yet, somehow we do not know that it is in meat! 3 ounces of beef has 267mg of it! wolframalpha is good for something.
If you are doing VLC, you are eating meat, in which case you are getting plenty of potassium. (If you are doing VLC and not eating meat I fear your time here on Earth will be abruptly curtailed.) You will not know that unless it occurs to you to actually check specifically how much potassium is in meat. Internet searches lead you to fruits and vegetables with nary a mention of meat!
A frustratingly perverse situation to be sure. One could almost assume some sort of conspiracy arranged, perhaps by banana growers, to keep us in the dark. Maybe vegan brigades are hacking into Google.
This happened to me. I was afraid to give up my daily banana, but I knew it was jacking with my blood sugar. And then, after years of worrying about getting enough potassium, I learned the truth. There was plenty of potassium in the brisket!
I've dealt with leg cramps and fatigue in the past, so when I went VLC I made sure to eat a lot of greens/spinach, herbs, fish, and I focus my occasional nut/seed snacks on those with higher levels of potassium (pistachios, almonds). I also switched my magnesium supplement to one that also has potassium, albeit not much (8% RDA).
Cocoa powder/unsweetened chocolate also has a fair amount, and I snack on 99% chocolate bars anyway. I also use some molasses in sauces, stews, etc (chili and bbq sauce especially!) when I learned that it was very high in potassium -- it's a great way to add some depth of flavour, and I'll gladly have the touch of sugar.
I've also wondered if there are natural salts or mineral water that have more than a trace amount of magnesium/potassium, if anyone knows? I didn't look for hours or anything but I couldn't find actual data on the quantities.
Will have to check out dulse too..
I've wondered how paleo man dealt with this during the times when he was forced to live on mainly meat. I can't imagine that he got muscle cramps all the time and just dealt with it. Did he get the potassium he needed from bones? Maybe bone broth is the answer for us?
I have been LC or VLC for a few years now, use sea salt, drink mineral water here & there and I work outside all day long sweating a lot - have never had the leg cramps, or other low potassium symptoms. But like anything else YMMV.
Beet greens have the most potassium than any other vegetable or food. Just make sure you steam them or fry them, because the potassium will go away in the water if you boil them. A cup of stir-fried beet greens is about 8 grams of carbs.
Use light salt. Not sodium-free salt (which tastes horrible).
It's essentially 1:1 NaCl KCl.
Use that on your meals, I think you'll be surprised it tastes fine.
(And for what it's worth I'm a big cook/foodie.)