High Magnesium Supplementation Experiments


EDIT: Read this post, the premise of these experiments was flawed. Result summary: If anyone else wants to go above 400mg of magnesium supplementation, go with chelated magnesium to avoid laxative effects and you won’t need to worry about the upper limit.

I’m in the process of testing out a recipe that follows the optimal micronutrient ratios compiled on this forum.

Everything else has come together nicely, except for my magnesium requirement of 900mg, preferably 1800mg in order to get a good calcium:magnesium ratio of close to 1:1. (720mg phosphorus->x2.5= 1800mg calcium) This is potentially problematic since, for those who don’t know, the safe upper limit recommended for magnesium supplements is about 400mg.

I am getting a decent amount from the “food” part of my recipe, and I’m supplementing the rest. The supplements I’m using are a blend of three sources (oxide, citrate, aspartate). Based on earlier discussions here, I’ve been hoping that spreading various forms of magnesium out over the course of the day and having it mixed in with the soylent would let me digest it more like a natural magnesium source and push over the limit of about 400mg from supplements.

To be clear, the “toxicity” of magnesium supplementation is all about the stool and laxative effects. So turn back now if you don’t like that talk :slight_smile:
(I only replace 2/3 of my meals with soylent, so there are other unquantifiable factors involved)

In short: it’s a bit complicated. Basically, I confirmed that in pill form you don’t want to go over 400mg. You can push it a bit by mixing, maybe a lot, but it’s turned into a blindfolded juggling act for me due to problems with getting the magnesium to mix up properly.

Week 1, I used 400mg from supplementation and 400mg from the food (rye, cocoa, etc), with the supplement mixed up thoroughly into the drink. I was getting a steady single bristol-3.5 movement per day. So far so good.

Week 2, I upped it to 800mg from supplementation, and there was no change. I figured for sure there ought to be a little change, though. Until this point, I had noticed there was a bit of a sedimentation problem. I assumed it was from all the minerals from all the vitamins I was crushing up, which is a problem some people have run into. A significant amount of sedimentation gets lost to the sink drain during cleanings.

So for a few days I was being aggressive with shaking my bottle before each sip and trying to get the last bits out of my nalgene bottle (making eating a chore). I think perhaps my stools at this point went from a bristol-3.5 to a 4. It wasn’t dramatic and could have just been due to other factors or random.

I eventually crushed up all my vitamins separately and put them each in a cup of water to get a sense of the sedimentation problem, and it turns out ALL of the sedimentation was coming from my magnesium. So I was likely never getting all of it in the first place, or at least the magnesium oxide (see below). I estimate with my aggressive sediment capture habits, I was still losing up to 10%.

Week 3, I decided to take my 2 magnesium caps in the middle of my soylent meals as separate swallowed capsules. At this point things got a bit messy pretty quick. I started getting bristol-5.5 to 6 movements, THREE times per day!!

Except for the occasional bristol-7 flatulence (happened twice in a controlled manner), it wasn’t a big problem per se, just really annoying and an obvious change. It wasn’t diarrhea, I wasn’t losing water, no nausea, confusion, loss of appetite, muscle weakness, difficulty breathing, or irregular heartbeat. However, I don’t feel comfortable suggesting that nobody would experience these things at this dosage level, or that I wouldn’t eventually if I kept it up. The obvious change in bowel movement to something generally considered unhealthy is not a good sign and not something I intend to let go on.

Week 4, taking only 1 capsule per day and things are returning to normal.

So it’s a real catch-22: In my recipe magnesium is the only one you can’t take separately, but it’s the only one that can’t be mixed easily. Back to the drawing board, I suppose.

It looks like the sediment is coming from the magnesium oxide (magnesium citrate and magnesium aspartate are both water soluble). So theoretically, I could be getting most of the magnesium when mixed. I don’t know how much of each of the three types I can expect in these capsules and I don’t know how much I actually ingest when I mix.

I’m thinking of new things to try now. If anyone has questions, advice or comments, (particularly about different magnesium sources and solubility) please give your feedback. I will post updates as I continue to try to crack this.


My doctor recently suggested magnesium citrate liquid to me. I haven’t picked any up yet, because I still have a large bottle of magnesium glycinate to finish off, but wouldn’t a liquid fix the problem of sedimentation?


What dosage does he recommend?

How much of the glycinate do you use?

Pure magnesium citrate costs about 5x as much for me. I was hoping that having a blend of various sources would help prevent the laxative effect… I guess that’s a no-go. Anyway, I still have a few hundred of these caps to get through, maybe I can do 1 capsule/day and then top it off with more citrate.


You should add a little water to the last amount and chug it down, otherwise you’re playing roulette with what vitamins you’re actually getting. If the sediment is too grody, then you need to just take the tablets.


I don’t honestly remember. I have it written down somewhere. I’m not necessarily following her guidelines when it comes to my soylent though - except going by the community guidelines…you’re right, that’s a lot of magnesium. If you start with even just the minimum for phosphorous to calculate your dosages for phosphorous/calcium/magnesium - that’s a LOT of mag. That put me at 7 pills for mag glycinate. When I bought those though, it wasn’t with high dosages in mind, so I don’t know if there are higher dosages available. My current pills are 400mg each.


Yeah, adding water is the only way to get them out actually. They get caught in the beveled 90 degree corner of my nalgene bottle. It’s all magnesium (oxide) though. Without the magnesium caps mixed in, there is no sediment.

Yeah, I’m beginning to think the only way to do it would be to make a bean, quinoa, avocado kind of savory super-priced soylent. Either that, or perhaps we’ve got it wrong by looking at the optimal P:Ca and Ca:Mg separately. My spidey senses are suggesting the balance may be different if all three are taken into consideration, but I can’t find anything on that, so…

Your magnesium glycinate may be the best form of supplement, though. Check this out. That’s a website for people with heart problems who need higher magnesium, apparently. The summary in particular seems promising:

The true amino acid chelated form of magnesium glycinate offers the benefit of fast and complete absorption without interference and without the adverse effects of bowel intolerance.

But then there’s also this

Many veteran afibbers experimenting with magnesium supplementation have successfully combined a variety of forms…


I can’t find a source that isn’t trying to sell something, but the glycinate form is apparently so highly absorbed that it is four times as effective as citrate. The previous more reliable source also said it’s more absorbable, and as far as I understand the situation, it’s the magnesium that isn’t absorbed which causes the laxative issues.

I imagine if you use glycinate, it would be sufficient to have your recipe closer to the 2:1 Ca:Mg ratio.

Are you interested in seeing what happens if you shoot for 3 or 4 pills instead?


I bought the glycinate a long while ago when I was doing research on vitamins to take along with this iodine protocol that I was doing and the info that I’d gotten was that the glycinate was the best absorbed and best tolerated. This woman that I’m seeing smh, I don’t know. She makes these recommendations, but doesn’t back them up with why. I asked her about why citrate and not the glycinate, and she said something about that she recommends glycinate for heart issues, but not for other stuff?? Whatever, I’ll prob stick with the glycinate then.

I did set my recipe to 3 pills. I’m also getting magnesium from my multi and from buckwheat, so between all three sources, I’m getting 1060mg. My calcium is set at 1.83g, and my phosphorous at .75g. We’ll see how that goes. I’m starting this recipe next Monday.


Awesome. Keep us posted! I’m trying to find a cheap form of glycinate, but it’s pretty hard in Japan. The best I’ve found so far would be about $0.5 more expensive per day just to replace half the magnesium. If you don’t experience any problems, I’ll probably go for it.

@vallaron mentioned this in his soylent recipe thread:
As for you magnesium problems i once read an article that said dietary uptake of magnesium was very inefficient due to the way we process it and that the best way to get it was through soaking in a bath with Epsom salts, absorbing it through the skin.I have used these baths before to help me after weight lifting sessions and my recovery increased greatly.

Have you looked into that way of upping the amount your body intakes?

That’s interesting. I don’t take baths often enough for it to be a reliable solution, but having epson salts around wouldn’t be a bad idea, I guess.


Epsom salts are magnesium sulfide ( I think) and it is absorbable through the skin. There is another liquid topical magnesium alternative though. A few years ago, I came across magnesium chloride “oil” (it’s not an oil, but in solution it feels like an oil on the skin) Now, you can buy magnesium chloride flakes from several different companies, or you can buy it ready made. OR, seeings how you’re in Japan! I bought and used Japanese Nigari to make mine. It’s the exact same thing, and it was super cheap.

The problem with the topical solutions, or even the baths, is that it’s difficult to measure exactly how much you’re getting. I know it works. I used it for a while when I was having severe insomnia. There were times when I could definitely feel myself relaxing after applying it. I have a friend who used to get severe charlie horses in his legs sometimes. Like, wake up in the middle of the night screaming kinds of charlie horses. We’d apply some of the magnesium oil, and it was really the only thing that would give him immediate relief.

I stopped using it on a regular basis because it was kind of a pita. I didn’t like the feeling that it left on my skin, so it meant that I had to apply it and sit around for 20 min to half an hour and then take a shower. Other people don’t have that issue, and swear by it. Google magnesium oil.


Oh, neat - I just confirmed that epsom salts have sulfur too. Sulfur is a miracle ‘drug’ for skin problems, and in hot humid summers here. Definitely going to try it. I don’t think it’s a problem that we don’t know how much magnesium we absorb through the skin (unless you’re on a low calcium, high magnesium diet and do this bath every day).

In the meantime, I have extracted the non-soluble portion of my magnesium supplement, which I will assume is close to pure magnesium oxide.
I have also extracted a couple days worth of the sediment that’s left after drinking my soylent normally.

Tonight I’m going to measure them and compare to the mass of the supplement as a whole. I should be able to get a reasonable estimation for what % of the magnesium I’m losing through sedimentation. Once I have that, I’ll readjust my numbers and keep raising my magnesium until I get problems again.


Ok, so I’ve estimated that in week 2, when I was supplementing with 2x 400mg caps, I was only getting a total of 640mg ingested after sedimentation losses. Due to my 2/3 meal replacement I was actually only ingesting just over 450mg of supplement per day.

I had no problems, so I will continue from there, starting tomorrow, by upping the dosage to 3x 400mg caps. (1020mg/day for the recipe, 680mg of actual ingestion)

In this image, from right to left, I have the content of a capsule (1300mg) the non-soluble portion of a capsule (300mg MgO), and the sediment that gets lost through normal drinking habits (100mg MgO). I measured 2 trials for the sediment and there was basically no variation.

Molecular Mass for MgO: 40.3g/mol
Atomic Mass of Mg: 24.3g/mol

Mg content of MgO: ~60%

0.6 * 100mg = 60mg of Mg lost through the sedimentation

So of each 400mg capsule, if broken up and mixed evenly in my soylent, only 340mg of it gets into my system. (More if I try real hard to eat the sediment, but that costs me more in time than the Mg is worth)

This represents an overall loss of 15%. Not good, but better than I was expecting. This only raises my cost of Mg to 15.3 ¥/g, whereas the cheapest magnesium glycinate source is still 165 ¥/g. So there is still value in determining how far we can push the mg supplement upper limit when the magnesium is varied and spread out through food.


So 3.2 g of this should give me around 800mg of magnesium?

Also this is $0.07 per g (6.84 ¥/g I think?) But I don’t think you can purchase this in Japan…


Wow, that is killer cheap. Although it is better to look at the cost per gram of magnesium than the cost per gram of the chelate. It’s ~$0.30/g of Mg. That’s only twice what I’m paying for Mg that supposedly has 4x the absorption; so it’s still a great deal.

I actually have been able to find source naturals Magnesium “chelate” (unspecified amino acid) for about $0.70/g on amazon Japan. That’s still more expensive, but just cheap enough to warrant getting it, for me.

Experiment update: All last week I’ve been ingesting roughly 600mg of non-chelated magnesium spread evenly in my soylent, and have not had any issues yet.

I plan to stay with 600 from my current sources and slowly start adding my new chelate once it arrives.


Oh wow it took me a while to get that you were using the Mg abbreviation for Magnesium, before it was like wait why did he say milligrams in the middle of that sentence :stuck_out_tongue:

That website has lots of really cheap stuff on it for the Americans.


It doesn’t help that I’ve been inconsistent! Sorry m(_ _)m


With my current recipe, I have 1300mg of Magnesium/day.

  • 400mg from food
  • 600mg from normal magnesium supplements (oxide, citrate, aspartate)
  • 300mg from magnesium chelate supplement

I’m eating 2/3 of this soylent per day, so each day, I’ve been ingesting ~867mg from soylent:

  • ~267mg from food ingredients
  • 400mg from magnesium citrate, oxide, and aspartate
  • 200mg from magnesium chelate

I’ve been taking this for a little over a week now. Results:

  • My stools have been solid bristol 3s and 4s, one or twice per day.
  • I just had my first blood test done this weekend and the doctor says everything looks perfect.

The next step will be to eat this soylent as a full meal replacement for at least a few days straight to see what happens.


I only managed to do one day of full soylent meal replacement for the full 1300mg Magnesium dose (there were no issues); I won’t be gathering any more anecdotal evidence than that, unfortunately. It’s hard for me to do full meal replacement due to lifestyle considerations, and there’s been a development on the Optimum Ratios thread:

The 2.5:1 Ca: P ratio was based on an erroneous interpretation (It’s for blood content, not diet). That dramatically lowers the need for Calcium, and therefore magnesium in my recipe, so I’ll be dropping down to something more like:

  • 800-1000mg total Mg
  • 400mg from food
  • 200-400mg from supplement (oxide, citrate, aspartate)
  • 200mg from chelate

The key number there is 400 from normal supplements and 200 from chelate. That is the amount I’ve been ingesting over the past few weeks on my 2/3 meal replacement diet. So with my new recipe, there is no need to do a full meal replacement test anymore.

As far as I’m concerned, at this point, my experiments are concluded. Thanks guys.