Comments for Magnesium and Kidney Function

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Don't Be Frightened
by: Kerri Knox, RN- The Immune Queen!

Hi Priya,

As usual, excellent questions.

Don't be frightened though. There are several reasons why this is just not an issue for almost anyone.

1) The VAST majority of people, especially the elderly, who are looking at magnesium as a solution to their health problems have HAD kidney function tests. Anyone who has had a 'routine' blood test has almost certainly had their kidney function tested and since even VERY minor kidney function abnormalities are concerning, almost everyone would know if they have kidney problems.

2) You do NOT need to get a kidney function test after starting magnesium if you had one before taking magnesium. Magnesium in no way HARMS the kidneys, it can just build up to dangerous levels if you DO have kidney function problems. So, once you check kidney function, then it's safe for almost everyone with normal kidneys to take magnesium.

3) People with kidney function problems are usually QUITE sick and would almost always have been to see a doctor about their problems. Even those who live in a remote location would be likely to be sick enough to travel a long distance to see a doctor about their problems. There are just VERY few people walking around with kidney function problems who aren't aware of it.

4) Yes, if you are urinating normally and don't have swelling and your 'intake and output' is essentially similar, then it's very likely that you have normal kidney function. There are a very few exceptions to this of people who have normal urinary output with poor kidney function, but this is VERY rare and again- it's likely that they are quite ill and are already aware of this problem.

Unfortunately, there is NOT a safe dose that 'everyone' can take because those with kidney failure can overdose even taking small amounts and should never take magnesium except on the advice of their nephrologist (kidney doctor).

In any case, even if someone WERE to not have access to kidney function tests and are concerned that they might have an undiagnosed kidney problem, they could simply read my page on Magnesium Overdose before starting magnesium therapy. If they suffer from any of these symptoms or feel WORSE after starting magnesium, then they could just stop taking it.

No one should feel worse taking magnesium. They should feel better or feel nothing.

Hope this alleviates your concerns...

Kerri Knox RN Immune Health Queen

Kerri Knox, RN- The Immune System Queen
Functional Medicine Practitioner
Immune System

thanks for clarification on Magnesium and Kidneys
by: nathji

Dear Kerri,

As always you have all the answers and they are the best that can be had anywhere in the world. I am grateful for your getting rid of the "kidney fears" that I had, regarding magnesium. I am now going to your page on Magnesium Overdose and enlighten myself further!

Thank you again for this wonderful site and the wonderful way in which you help people all over the world!! Its the best site on the internet!!

Best wishes,

magnesium and the kidneys
by: nathji

Dear Kerri,

Could you let me know whether I should take Magnesium as I last had a creatinine of 1.2 in 2002 and havent measured it since then for lack of a lab where I live?

Also, how much does the creatinine change over the years all by itself-- with age? I am 69 now.

Then again is it true that muscle fatigue releases creatine and that converts to creatinine and thus raises the creatinine in the blood, which worsens the kidney function?

I am taking magnesium for leg muscle fatigue -- but what if this leg muscle fatigue is making the creatinine go up and this is worsening the kidney function silently without any symptoms? Should I still be taking magnesium?

Should I be afraid to walk and of leg muscle fatigue for the above reason?

This would be a typical catch 22 situation.

Your advice would be invaluable as always!

Magnesium and Kidney Function...
by: Kerri Knox, RN- The Immune Queen!

Hi Nathji,

While creatinine can rise throughout life, the numbers stay VERY VERY stable all of the time and should always be within the normal range. Even quite elderly people may only have a creatinine that is just very very slightly over the high limit.

It's surprising what a 'tight' range creatinine stays in regardless of health problems, age, etc and it should always be almost completely normal- except with kidney disease.

Jigsaw Health - Sh!t You Not - $10 off

Muscle FATIGUE does not cause the release of anything, while muscle DEATH releases a substance called Creatinine KINASE- not creatinine. The creatinine portion does need to get filtered out by the kidneys, but rarely does a transient rise in CK (as with a heart attack or with a marathon runner) even result in an increased Creatinine or even slightly impaired kidney function.

While large amounts of CK or CPK (Creatinine Phosphokinase) along with dehydration can cause a condition called Rhabdomyolysis that releases HUGE amounts of CK- and can lead to kidney failure, the small amount that might be released from a very gradual muscle wasting from a leg would be unlikely to harm the kidneys in any way.

People who get Rhabomyolysis get it suddenly and are VERY VERY sick- it almost always requires a trip to the hospital. So, that is not a worry for you either as it the ONLY cases of Rhabdo that I have seen in over 10 years of working in emergency rooms are:

* Drug or alcohol induced (statin drugs included)
* Someone who has had a major traumatic event (car accident, stroke)
* Someone (usually an elderly person) who fell and couldn't get up and wasn't found for 2 to 3 days

It's usually a VERY traumatic event that causes VERY high CK's that would induce Rhabdo that would lead to kidney failure and not something to worry about.

I would NOT suggest that you stop walking as that would lead to more muscle wasting, not less!! Keep active, keep moving!

But again, if you take too much magnesium- whether it is from poor kidney function or for any other reason- you will feel bad. Taking magnesium should in no way make you feel bad, so if it does then you should just stop taking it.

Kerri Knox RN Immune Health Queen

Kerri Knox, RN- The Immune System Queen
Functional Medicine Practitioner
Immune System

by: Priya Nath Mehta

Dear Kerri,

I cannot thank you enough for your enlightening reply and the exactness of your advice and knowledge which is always for the betterment of all of us!
Thank you, I shall do as you have advised!!
I am so grateful to you!

Your admirer and fan,

Guess I'm *unusual*
by: Vee

Hi there, Just felt I should comment here, as I'm searching for ways to IMPROVE my kidney function, which by medical standards has qualified me for dialysis, & stumbled across your website. I am not doing dialysis. In fact, I didn't even know I had a problem.

Got sick with something else, they did some baseline tests, and imagine my surprise to find out that my gfr was 8. It has so far gone up to 11, but I am attacking this (as well as 2 other issues) holistically, carefully, diet, exercise, naturopathic drs, & trying to stay as far from the medical community as I can.

I do take saltbaths including the use of magnesium flakes 5 times/wk. All my normal functions are just that - normal. No swelling/fluid retention, no decrease (or increase) in urine output. I feel amazingly well & energetic. The MDs are confused by all this (me too actually).

I have a positive attitude, willing to change my entire lifestyle in ALL ways to regain my health, and so far my body has cooperated with that. Just wanted to tell a bit of my story here. Thank you!~~ Vee

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