Do blood tests accurately measure electroylytes?


(Troy John) #1

Got my tests done and I am on the low end for Sodium and Magnesium. Does this mean I should be upping my intake?


(Bob M) #2

A very good question. Some people think that other tests are more accurate. They have tests where they measure these in red blood cells (I think, anyway), and these are supposedly a better indication of what’s really in your system, as your body will do everything it can to make sure the electrolytes in your blood are in a narrow range.

As for your tests, do you find anything is off? Some people get heart palpitations, some get tired, some (like me) have muscle cramps, some have other indications that something is off. Not all of this is caused by electrolytes, but many can be.

If you feel great, then I wouldn’t worry too much. If something is off, consider more salt and magnesium.


(Bacon is a many-splendoured thing) #3

Magnesium, calcium, potassium, and sodium are regulated by interlocking mechanisms. The key is sodium, because it’s the easiest to control our intake of it. If you are getting headaches and constipation, then eat more salt. If your stools are too loose, cut back on the salt.

I’m surprised your sodium was low, because serum sodium is tightly regulated. Serum magnesium is tricky, because it’s not, apparently, a good indicator of whether we have enough magnesium or not. But low magnesium can cause muscle cramps, which might be an indication that a magnesium supplement could be helpful.

However, if you are not experiencing symptoms, you are probably okay. But I’m not a doctor, so you should probably ask your doctor what he or she thinks.


(Joey) #4

My “go to” source for the best science presented in layman’s terms (but with extensive citations to explore) is Dr. James DiNicolantonio’s “The Salt Fix.”

Might be worth reading if you’re concerned about your levels or intake.

But generally, as noted above if you’re not experiencing adverse symptoms (and there are a lot of potential ones from which to choose :wink: ) then you’re not likely far out of a healthy range.

FWIW, carb restriction is well known to generally increase one’s need for electrolyte intake along with greater attention to maintain hydration given the associated water/weight loss.


(Troy John) #5

CTViggen; Thank you. The one thing ‘off’ is frequent urination which has always troubled me since going keto, but it is more pronounced. I do take the recommended sodium intake-2 tsp on top of food, but that does not seem to help. I know I have read one should/could take up to 3 tsp of extra salt but am unsure if that is the right thing to do.


(Troy John) #6

SomeGuy, thank you for the book info. I will definitely read it.


(Bob M) #7

That’s interesting about the more-frequent urination. I have that because I’m an older male, :grinning:, but I guess keto could cause that too, as essentially you’re peeing out more, which is one reason why blood pressure typically goes down (you’re not holding onto extra water).

Personally, I just put a bit of salt in my coffee in the morning, and salt my meals. If I’m fasting, I’ll take salt under my tongue, but that’s to stave off hunger (which it does do). And if I have cramps, I’ll increase both my salt and also magnesium. I have a soft water system at home that uses potassium, so I think I get enough of that.

Since it’s getting colder, I’ll likely taper off some of the salt intake. I shouldn’t be sweating as much. But we’ll see.


(Troy John) #8

CTviggen, thank you for responding. Curious, as I am also older. How frequent do you pee in the night (keeps me awake), did it get worse starting keto and have you done anything about it?


(Jane) #9

When I ended up in the ER with a severe gallbladder attack, they put off the surgery for a day because my sodium was too low and I was told it was dangerous to do surgery unless it was to save my life. They brought it up gradually through normal IV fluids and by the next day was in the normal range so they removed my gallbladder.

My potassium was low the second day, but they weren’t concerned about it and gave me a potassium pill.

I hadn’t been able to eat anything for 3 days prior so I am assuming that is why my sodium was low, plus I was ill.