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Transdermal Magnesium Chloride: Probably Bunk

I recently conducted experiment on myself using Transdermal Magnesium Gel (not the "Oil").

My RBC level was 2.13nmol/L or 5.18mg/dL

I went through 2 bottles over a 2 month period, a 700mg/day dose. I allowed the gel to sit for 45 minutes to 1 hour.

My RBC level was 1.63nmol/L or 3.97mg/dL

I somehow went from mid-range to deficient. My diet, exercise, caloric content did not change.

Granted, the blood vials could have been mistakenly mixed up. But since (to my knowledge) there haven't been any comparative studies to see how transdermal compares to oral forms and placebos, this product remains suspect anyway. For those who haven't been using it, you can conduct a similar experiment for yourself.

I'm redoing the experiment using 800mg/day of magnesium citrate (better then oxide) for 45 days to see how that turns out.

If anyone else has tried something similar, please share. I'm curious of the results.

asked Dec 8, 2013 by AC

I think RP commented to someone that topical mg isn't enough to compensate for a deficiency in the diet. I concluded that I should focus on getting plenty quality orange juice of the highest quality, then on the occasional bad days have some mg supplement on top of that. Foot bath of MgCl2 ("magnesium oil") definitely has a relaxing effect for me, so it must be going somewhere even if it doesn't stay there long.

6 Answers

Nice experiment. Read this detailed analysis of a doctor over at worldhairloss, that also states that magnesium oils and gels are pretty much worthless. Only useful transdermal way would be taking a bath in epsom salt every day for several weeks (only that has been shown to increase levels). It's probably easier to just take a oral supplement.

I'm really curious to see the result of your oral supplementation period.

answered Dec 8, 2013 by Bukowski

I make my magnesium oil by myself and believe me, if the concentration is high enough it definitely works. Just one week ago I zonked myself out by applying an extra strength mixture. I got the symptoms that are seen if you go overboard with intravenous mag, i.e. Hypermagnesemia. Please also read here:

Good luck with magnesium citrate. If I use that the shit hits the fan literally. The net effect of that kind of diarrhea would be even more magnesium loss I think.

answered Dec 8, 2013 by nograde

Also for magnesium via nutrition I would suggest dates, which are exceptionally high in mag. And strong coffee/espresso if you can handle it.

Chronometer tells me 43mg magnesium per 100g, which is pretty average (i.e. buckwheat has 251mg or oats have 138mg). It has extremely high amounts of potassium though.

Dates are much more delicious than buckwheat, though. It's not a well known fact, but deliciousness is actually the most important factor in magnesium absorption.

Bukowski: compare that to the 11mg OJ gives you ...


Although I love buckwheat pancakes.

I like buckwheat crepes, adding enough milk and eggs to make them very thin and crispy + a lot of sugar. Very rewarding, but not as overwhelmingly sweet as dates. Quite a lot of tryptophan though...

I also make a lotion out of coconut oil, beeswax and magnesium oil. I would think this would absorb worse than magnesium oil on its own, but it doesn't sting and still helps me with pain pretty well.

"it's not a well known fact, but deliciousness is actually the most important factor in magnesium absorption." Dewit, do you have a study for that?:P

I don't know if RBC level is all that accurate; it seems a 'loading test' gives a slightly better picture of absorption (though no current measurement is perfect):

This study took pre and post MgSO4 intravenous infusion serum and RBC levels and they didn't really change, which I think is telling (Table 1):

I'm not sure why your levels went down (maybe more deposited into your tissues?), but I'd go by 'dat feel.'

answered Dec 8, 2013 by Adam Cap

As far as I know, there is only one study which tested transdermal MgCl and it found that it does indeed have a positive effect. However, the study is not listed on pubmed and used a particular brand of magnesium oil, instead of using medical grade magnesium chloride hexahydrate. Also, they used hair analysis. I suspect a high level of bias, but it may be interesting for some nonetheless.

There you go:

answered Dec 8, 2013 by Dewitt

you mentioned that there isn't much absorption of magnesium with epsom salts. any studies that test magnesium flakes? apparently, you can buy them for baths.

Nope, I don't know of any studies about that.

If you receive sun exposure, I wish you tested changes in vitamin D. Magnesium seems to increase levels of both active and inactive Vitamin D.
answered Mar 17, 2015 by john
Did you measure your TSH?

Magnesium injections reduce TSH.
answered Mar 19, 2015 by john