I would like to to have my calcium and magnesium levels tested with Medichecks but I am unsure which calcium and magnesium test I would ask for? Which would be the most reliable one to go for? I would like a finger prick one if that is possible as don't have anywhere I could go to to get a vein one done.
Many thanks for any guidance
ionised calcium is a simple test your GP can do (if they are helpful). Magnesium blood tests are of little use they do not reflect intracellular levels. As regards magnesium the best test is to try supplementing and see how you go.
Like all these companies they are commercial. They do state 'Most of the magnesium in the body is found in the bones and inside the cells. Only a tiny amount of magnesium is normally present in the blood.' but fail to point out it is the intracellular levels that matter. They offer a 'red cell' (RBC) test which is a bit better but still only measures blood levels not intracellular. The gold standard is the 'magnesium loading test' where they give you magnesium and measure how much is absorbed. At home, just taking magnesium and seeing how you do is almost as good and much simpler.
Thank you Jim - your info has been very helpful. I am now embarking on taking 300 mg of magnesium citrate per day to see how I go. How do you know if you have had too much?
That's handy because I've use magnesium citrate and so I'm familiar with it. I've taken up to 400 mg daily and it's OK. Take it in divided doses (twice daily?) and away from thyroid hormone, it can impair levothyroxine absorption.
The only time you should not take magnesium is if you have low blood pressure or impaired renal function (kidney disease). In these cases you should consult a doctor.
As your tissue levels of magnesium improve the body will reduce its absorption of magnesium from the gut. If you fail to absorb magnesium citrate it can act as a laxative. So, your toilet, clever little thing, will tell you if you are taking too much magnesium! Don't worry at the doses you are taking it would be a slow progression to softer stools, so you could back off early. It can take many months to restore magnesium levels so beware that a dose you can tolerate now may be a little too much in three months time.
The other issue about magnesium is that hypothyroidism causes lower intracellular magnesium levels, a 'shift from the intracellular to the extracellular space', so it's important to adequately treat hypothyroidism. On the other hand, hyperthyrodism or thyrotoxicosis leads to renal loss of magenesium. So, getting thyroid right is important.
(For those of you who are going to ask for the evidence: I've looked hard for relevant studies but can't find any good ones. I've taken the above information from Jean Durlach's out of print book 'Magnesium in Clincal Practice'. Prof Durlach is the leading expert on magnesium.)
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