For transdermal magnesium, I have tried on my skin both:
• Magnesium oil, which is not an oil at all, but just magnesium chloride crystals dissolved in water, which for some reason has an oily texture.
• Magnesium sulfate crystals (Epsom salts) dissolved in water, which does not have an oil texture.
I much prefer putting magnesium sulfate dissolved in water on my skin, because this does not feel sticky like magnesium oil, and also it does not irritate and itch the skin like I find magnesium oil does.
The magnesium content of magnesium sulfate is comparable to magnesium chloride, so they are both effective ways of absorbing magnesium through the skin.
If you want to make life easy for yourself, just get an empty plastic household cleaner spray bottles (like the one shown), fill it with warm water, and dissolve in the Epsom salts. Then you can just spray this Epsom salts solution on your skin from the bottle, and in my experience it works great.
Actually what I do is spray a bit of solution from the bottle into the palm of my hand (rather than spraying directly on the skin), and then rub that onto my skin.
Household cleaner spray
bottle containing magnesium
sulfate dissovled in water
I sometimes just spray just my leg area, and rub in. It takes only two minutes to dry, and then you can put your clothes on. If I want a larger dose of magnesium, I spray over my entire body, from head to toe.
You don't have to wash off this Epsom salts solution, because it dries in after two minutes, and it does not itch or irritate at all, unlike magnesium oil, so I find you don't even know it's there. This means that you can go on absorbing the magnesium for a longer period of many hours.
I use a 750 ml (25 oz) cleaner spray bottle, and this lasts me months of daily application.
When you are making up a bottle like this, a surprising amount of Epsom salts crystals can be dissolved in the water. I get around two mug fulls of Epsom salts crystals to dissolve into one bottle. I tend to make the Epsom salts solution as concentrated as possible.
Since you can buy a 1 LB of Epsom salts crystals for a couple of dollars / pounds at a pharmacy, this is also a very inexpensive source of transdermal magnesium.
I calculated that if you are using a standard 750 ml household cleaner bottle like the one in the picture, and you dissolve two mugfuls of Epsom salts in that (which is about 500 grams in total of Epsom salts), then:
Each spray will contain around 100 mg or so of elemental magnesium.
These household cleaner bottles deliver 1 ml of liquid per spray (when I tested them), so that's how you can do the calculation.
I typically use 20 or so sprays to cover my whole body, so that will be a total magnesium dose of 2,000 mg = 2 grams.
It's not clear what percentage is absorbed through the skin, but I would estimate that a good 50% is absorbed, so that would amount to 1 gram of elemental magnesium actually entering the body from 20 sprays.
This study on the absorption of magnesium during an Epsom salts bath in 19 individuals found that after a week of daily Epsom salts baths, on average the blood magnesium levels increased from 105 ppm to 141 ppm. The concentration of Epsom salts in these baths was just 1%, which equates to 600 grams of Epsom salts in a 60 liter bath.
So given that my saturated solution Epsom salts spray is much more concentrated than 1% (I use 500 grams in 750 ml, which works out as a 67% concentration), I would guess you get a greater absorption of Epsom salts from my spray method than you will from a bath. Plus my method is much more economical than a bath, which requires 600 grams of Epsom salts for each bath.
Other studies on transdermal magnesium
here.
If applying magnesium sulfate daily for long periods, it is advisable to consider oral calcium supplementation, as calcium and magnesium really need to be consumed in a certain ratio. If you do not take calcium, what happened to me may also happen to you (I developed an
incredible unconscious craving for milk!).