Everything You Need to Know About Magnesium

Robert Rountree:

This is The Thorne Podcast, the show that navigates the complex world of wellness and explores the latest science behind diet, supplements and lifestyle approaches to good health. I'm Dr. Robert Rountree, Chief Medical Advisor at Thorne and functional medicine doctor.

As a reminder, the recommendations made in this podcast are the recommendations of the individuals who express them and not the recommendations of Thorne. Statements in this podcast have not been evaluated by the Food and Drug Administration. Any products mentioned are not intended to diagnose, treat, cure, or prevent any disease.

Hi everyone, and welcome to The Thorne Podcast. We're really glad you're here and excited to talk about some fascinating topics for you today. I'm joined again by friend of the pod and Thorne Vice President of Medical Affairs, Dr. Amanda Frick. How's it going, Amanda?

Amanda Frick:

It's great, Bob. How are you?

Robert Rountree:

I'm good, I'm good. Good energy, enjoying life.

Amanda Frick:

That's all you can ask for.

Robert Rountree:

So, that's all you can ask for. All right, it's time to get into the main topic for this week, the mineral magnesium and its role in the body. So, what is the big deal about magnesium? I mean, what's important about it? Why would anyone care?

Amanda Frick:

I think that you should care, because it's easier maybe to answer what magnesium does not do in the body than it is to answer what it does do, because it does so many things. I mean, it's a mineral, a macromineral is what I would call it that makes up the structure of so many different things in the body.

So it contributes to the structure of bones and teeth, it's important for organ health, multiple organs in the body. It's regulating how other minerals are transported through membranes or muscle fibers or utilization in the body. It's part of probably hundreds, I don't know, thousands of biochemical pathways as a co-factor for so many different things. I mean, what does it not do is easier than what it does do, so that's why you should care.

Robert Rountree:

I was at a conference many years ago, oh, it's been almost 30 years I think, and one of my mentors, Dr. Sidney Baker, was doing the keynote, and at one point he had them turn off all the lights in the room and he pulled out a strip of magnesium and lit it, and it was amazingly bright when it was burning. Now, his point was this is what miners used to use in their helmets. They would burn these little strips of magnesium and that's what they used as a flashlight.

Amanda Frick:

That's cool.

Robert Rountree:

It's really cool, and why he did that in a conference on health was, he said, "This is an example of how much potential energy magnesium can be involved in, and all of its different interactions." So one of the things I learned about magnesium is that it combines with ATP, so in order to make ATP, which is the energy currency in the cell, you need magnesium, which is not the same as saying, “Oh, take magnesium and you'll have energy.”

But the converse is true. If you don't have enough magnesium, then all kinds of things can go wrong, so that's a lead in question. How can people get deficient in this and what kind of issues would come up if they are deficient? So, why is magnesium deficiency so common?

Amanda Frick:

So, I think that's actually cool and debatable about who you ask, right? So a traditional medical system would say it's rare or difficult to become deficient in magnesium, but functionally we would say that it's one of the most common nutrient deficiencies that someone can have, so it depends on how you look at it.

Robert Rountree:

Yeah.

Amanda Frick:

But I think poor diet is part of it, increased stress or demand on the body to utilize magnesium for other things, possibly certain medications can deplete magnesium, added stress. Then also, some things like extended bouts of diarrhea or other conditions that may deplete nutrients can deplete something like magnesium as well.

Robert Rountree:

What about diuretic medicines for hypertension or congestive heart failure?

Amanda Frick:

Yeah, I think that would go back to medication interactions or medications causing problems.

Robert Rountree:

So, people can actually pee out magnesium?

Amanda Frick:

Pee it out, you can have it go out in other areas, but it can definitely make an exit when you don't want it to, by multiple mechanisms.

Robert Rountree:

No, I mean, I haven't looked at the literature on this in a while, but I remember there was a concept of something called magnesium wasting syndrome. The idea was that if you're under a lot of stress, then you actually do urinate out more magnesium. I don't know if they understood why that was, but I think it was studies that were done in Germany decades ago in animals that showed that was clearly the effect.

I can say I do have patients that have chronically low magnesium, and when I measure it in their urine, it's much higher than it ought to be. So I think part of it is that we may not be getting magnesium in our diet, because we eat as a whole a lot of refined food, ultra-processed food that doesn't have magnesium in it.

Amanda Frick:

Yeah, I mean, it's kind of like a lot of other healthy minerals, you're getting them from whole grains and nuts and seeds and beans and then green leafy veggies. I mean, most dense nutrients you can get from those things, but we eat refined grains and strip out the nutrients or people aren't just popping walnuts and almonds. Some people are, but maybe not enough, and then even how much of a bad name have beans gotten in recent decades and are people eating beans anymore? And then-

Robert Rountree:

They're all worried about lectins or…

Amanda Frick:

Yyeah, something. So I think there's a lot of food options out there, but how much we actually eat of those foods is the other side of the story.

Robert Rountree:

So, there's a lot of different ways you can get deficient, right? You can not be getting enough in your diet, you can be taking a medicine that makes you lose it, or you can be under a stress condition that makes you lose it. What's the consequence of not having enough? Well, first of all, how would you know if you're low in magnesium? This is a two-part question, right? One is, is there a blood test you can do? Just a standard blood level of magnesium, is that adequate? And are there conditions or symptoms, et cetera, that would develop as a result of deficiency?

Amanda Frick:

So, I think there's a couple parts to both of those. If you're severely deficient in magnesium, from a medical perspective you could have issues with your heart, you could be at risk for heart attack or stroke, you could have issues with bone density, you may have increased in chronic health problems like diabetes and other metabolic factors, so it can be really serious. Conversely in functional medicine when we talk about nutrient deficiency, we're talking about optimizing wellness or we're talking about having an optimal health experience, but you can be severely deficient in magnesium and cause serious health problems.

Other than that, I would say that some of the gentler aspects or functional aspects that you may notice if you aren't getting adequate magnesium in your diet could be issues with bowel regularity. Maybe your bowels are not moving as regular as you would like them to or they're difficult to move. Some people would experience an increase in anxious thoughts or maybe they're having difficulty sleeping, because magnesium can support restful sleep, magnesium can support a balanced mood, so they're going to be some more subtle things that you may notice.

Now that could be other nutrients as well, so talking with your practitioner, getting a better idea of what that looks like for you is really important, but the great thing is, it's magnesium. If you take too much, you can relax your bowels too much, and so you can…

Robert Rountree:

Yes, I like that word relax. It could relax your bowels.

Amanda Frick:

Yeah, you may want to relax your muscles, but your bowels are a muscle, and so you can over-relax that and experience loose stool. But other than that, there's not a lot of risk, or if it's something that's worth trying for you, it's a pretty safe thing to try to increase magnesium in your diet.

Another time I would use it a lot are people taking medications, like we alluded to already. I really frequently would add it to protocols with my patients who are taking things like a birth control pill or some other hormonal contraceptive. I always added that into something to rebalance there.

I think your other question was about blood tests, so you can test magnesium in a normal blood test. Whether I think that's useful is questionable. Unless you're looking for some gross imbalance that would be transient in the blood, it's probably not giving you the functional information you need, so you'd be looking at some more sophisticated nutrient tests or maybe whole-blood analysis sort of tests to see what the functional amount of magnesium is in the system.

Robert Rountree:

So, my understanding is that you really, really have to be severely depleted in magnesium before your serum magnesium level drops, right?

Amanda Frick:

Right. That's when you're looking for those severe health effects.

Robert Rountree:

So it's severe health issues, but it's still something that people, if they're going to bring it up to their doctor, and if they're worried about magnesium deficiency, it's something they could easily ask for, because it's a standard test, but a better test is to measure magnesium inside of red blood cells, called just RBC magnesium, because that really is like doing a tissue biopsy, right? That's saying how much magnesium is inside your cells, and that's what we want to know.

Amanda Frick:

There's a lot of other nutrients you'd prefer to test that way as well. I always thought it was funny that I'd have a patient come in and say, "Oh, my doctor said I don't need calcium. My blood test's normal, I don't need calcium." So, it's the same thing.

Robert Rountree:

Oh, yeah, I got plenty of calcium in my blood. 

Amanda Frick:

Yeah, if you didn't you'd be having an issue.

Robert Rountree:

If you had low calcium in your blood, you're in big trouble, right? You're not just deficient, something weird is going on.

Amanda Frick:

Well, the converse, too, true. That's the other thing they would say, like, "Oh, you're taking way too much B12. You definitely need to stop taking your B12, your B12's super high in your blood test." OK, well, you took it that morning before you went and got your blood drawn.

Robert Rountree:

Right, right. Those tests for things like B vitamins ... in fact, most nutrient tests, the normal levels were determined in people that weren't taking supplements, which I think is a little bit weird. Then if they're abnormally high, then a more mainstream untrained doc would say, "Yep, your B6 is too high, your B12 is too high." Well, no, those levels weren't based on people taking supplements.

Amanda Frick:

Well, and the same as what you were saying, we don't know what's getting into the cell either, that's just what's floating around in there. When you get your blood drawn, it's not really an adequate representation of what's happening in your body with it. There are other options, especially for something like B12, but just measuring serum B12 is not the way.

Robert Rountree:

One of the fascinating pieces of research I've run into with magnesium is its effect on something called heart rate variability. So, we used to think that when you measure heartbeats, that they should be pretty precise. If you've got a rate of 60 beats per minute, that's your resting heart rate, then that was exactly 60 beats per minute. But a healthy heart doesn't beat at exactly that rate, it's every beat is a little bit wider or a little bit shorter, so that variability is what you see in a healthy heart.

There were a couple of studies that I came across a few years ago that showed that when people have subtle deficiencies in magnesium, not enough to make their blood level down, but to make their red blood cell level down, so their tissue levels were down, which implied that the level in heart tissue was down, then the variability actually flattened out, so the heart rate became less variable.

I thought that was very interesting, because HRV, as you know, is an indicator of overall health of the heart, right? It's not a medical condition, it's not a disease, there's not an international classification of disease code for abnormal heart rate variability, but it is one of the best wellness tests for the heart that there is.

Amanda Frick:

I hadn't seen that research actually, I would love to look at that.

Robert Rountree:

The thing is people don't have to take massive amounts of magnesium to get it back in shape, they can eat more magnesium in their diet. That's a little harder to do if they're actually deficient. So I guess that brings us into a question, why would somebody want to take a magnesium supplement, versus just get a list of high magnesium foods?

Amanda Frick:

Part of it may be caloric density, part of it may be, like you were talking about lectins, maybe those items are not a part of a diet that they are partaking in. You can get magnesium in almonds, but almonds are not a low calorie food and you'd have to eat a decent amount of almonds, and sometimes maybe you just want a more targeted response.

I think you can get really nitpicky about it too, but there's so many different types of magnesium supplements that you could take that are sort of known for having a more effect on one thing or another. Maybe some types are better at supporting muscle relaxation or helping the muscles to relax, some may be better to purposefully help to regulate the bowels, because bowels are moving slow. Then there are other types that we talk about being able to cross the blood barrier because of what they're attached to, and those are more targeted to affect mood or help to support a balanced mood.

So you don't know that you can sort of target the direction your magnesium's going to go with your almonds, but the type of magnesium you supplement with could maybe give you a better way to target your desired effect with the supplement.

Robert Rountree:

So, it kind of gets to that bigger issue of should anybody take a supplement? You always hear somebody in the mainstream press saying, "You can get it all from a healthy diet." Then I go, "Great, what's a healthy diet? Can you please define that? OK, eat a healthy diet, you don't need supplements." Tell me exactly what a person should eat and tell me how many people are actually compliant with that.

I see supplements as being more of an insurance formula, right? It's insurance, especially if somebody is entering a stage of unwellness, they have that abnormal heart rate variability, if something is starting to go in the wrong direction, it seems like taking a supplement is a pretty easy way to start correcting that. Maybe they don't need to supplement forever, but certainly taking it until things start to normalize. Don't you think that seems like a reasonable suggestion?

Amanda Frick:

I think it's a reasonable suggestion. It's also, in most cases, a really cost-efficient thing to take, too. It's not like a large cost expenditure to try a magnesium supplement.

Robert Rountree:

There's a lot of different kinds of magnesiums out there. Why? Why not just take magnesium oxide? Shouldn't everybody just take the cheapest... You talked about magnesium, it's not that expensive. Shouldn't you just take the cheapest thing you can get?

Amanda Frick:

That goes back to what I was saying before about the different forms of magnesium and what they do. You maybe want to take magnesium oxide if you're trying to accomplish something very specific.

Robert Rountree:

Yeah, yes.

Amanda Frick:

And sometimes you might be, and sometimes that's exactly what your doctor would recommend.

Robert Rountree:

OK, so there is an over-the-counter protocol called milk of magnesia, right? It's not magnesium oxide, but it's designed to achieve a certain purpose.

Amanda Frick:

Definitely helps achieve that purpose.

Robert Rountree:

And if that's your purpose, then maybe you want the cheapest magnesium you can get.

Amanda Frick:

True, because it's going to go right through and out, which is exactly what you're trying to accomplish.

Robert Rountree:

That's because the magnesium, the molecule, the mineral pulls water into the intestines, so that's why it has that laxative effect. But maybe you don't want that laxative effect, in which case what kind of magnesium would you want to take?

Amanda Frick:

So actually milk of magnesia is magnesium hydroxide, so related, which is accomplishing that task, so really what it's about is it's not absorbing as well, and so it's in the lumen of your colon and then drawing the water in, which is how it's working in that way. So, it would be better to take a magnesium that's more efficiently absorbed in your digestive system so that you don't have it sitting around in the lumen and drawing water.

So, that's where a lot of times people will formulate with either different amino acid things like magnesium citrate or other chelated forms of magnesium for that reason, because it helps assist the magnesium crossing into the body where it can disassociate, and that's also why those different forms can help affect other areas other than just the bowels.

Robert Rountree:

So, the main advantage of a magnesium chelate, where an amino acid or something like that is bound to the magnesium, is it's better absorbed and less likely to let's say stimulate or over-stimulate the bowels?

Amanda Frick:

Correct. One of the benefits, yes.

Robert Rountree:

OK, one of the benefits of that. OK, now we got to take a short break and when we get back we'll take some questions.

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And we're back, so now it's time to answer some questions from our community. The first question this week comes from a listener who asks, "Is it OK to take magnesium every day? Or do you just take it when it's needed?"

Amanda Frick:

So, I think either one. I mean, again, it's depending on what you're trying to accomplish. If you're trying to accomplish some bowel regulation and you don't need it every day, maybe you take it for a targeted reason, but it's definitely OK to take it every day. It's included in most multi-vitamins, which people take every day. In general, like we've discussed, it's really hard to have a perfect diet, and so supplementing with some magnesium every day is safe and probably a good plan.

Robert Rountree:

Yeah, so there's not really a downside to it unless the person is having excessively loose stools. That would be the only time I would say, if somebody is complaining of the loose stools, that'd be the only time I'd say, “Well, maybe you should cut back and only use it intermittently.” 

But it could be a tradeoff. If a person has a condition where I think they could use support from magnesium, and they're saying, "Well, I feel loose stools," the first thing I would say is make sure you're using a form of magnesium like bisglycinate that's well-absorbed. I would do that first, and then if that's still a problem, cut back on the dose a little bit or maybe do it every other day. 

So, what foods are best for magnesium? What's really rich in magnesium?

Amanda Frick:

We talked about it a little already, but I think that goes back to I think whole grains, nuts, seeds, beans and leafy greens. Almonds. People think about almonds a lot. I don't know that they're the best nut, but definitely nuts and seeds in general.

Robert Rountree:

All the things that are not included in an ultra-processed diet, which is the American diet, right? If you're going to get fast food all the time, you're probably not getting magnesium.

Next question. "I've seen magnesium in topical oils and gel. Is it doing different things when applied topically versus orally?"

Amanda Frick:

So, interesting question. My grandmother and my mother would've had me use an Epsom salt soak, or I've even talked to patients about Epsom salt soaks, or when I was training for weightlifting competitions, I would use Epsom salt soaks to help with muscle tension, and I always felt like it helped me to relax. So empirically I don't know what that answer is, but I know at least from experientially that it seems to help or assist, like an Epsom salt soak, but I don't know a lot about the topical oils and gels. Bob, what do you think about that?

Robert Rountree:

Well, I spent some time a while back trying to find evidence that the topical forms were absorbed, even Epsom salts. It's an ionic form and cell membranes in the skin are fatty, so how do you get it across those membranes unless there's some kind of transporter? So, I did a lot of research trying to find studies that show that blood levels would go up after taking it, and I couldn't find any studies on that. Maybe I just missed something.

But that doesn't mean, as you said, that it isn't getting absorbed, we just don't have a lot of data or evidence that it's true. Certainly an Epsom salt, is that magnesium sulfate or something like that? If you've ever done that, you can feel it, you can feel your muscles relaxing, so some of it must be getting into the muscle tissue.

The one thing I'll say is I've tried a couple of commercial products of the gels, and they're really messy and not easy to use, so when I've recommended those to patients, or I didn't really recommend them, I just told them, "Well, if you want to try this, sure, it might help." People don't usually end up taking it for long, so their long-term compliance is not good, because it's really messy. Sometimes those gels can be really itchy to put on, so I haven't ever found a good formulation where I'd say, “Hey, this is something you can use long-term.”

Amanda Frick:

Why are people electing to choose a topical application?

Robert Rountree:

I'm assuming because they got diarrhea.

Amanda Frick:

OK, OK.

Robert Rountree:

Because they say, "I can't tolerate it that way. My guts react to it." Again, with people like that, I usually start with a much lower dose. I use something like bisglycinate and just have them titrate up, and usually people will build a tolerance.

The next question says, "I think more of magnesium as a metal, or the stuff that burns white in fireworks," which is what I had mentioned earlier. "Isn't it weird to think about eating it?" I love that question. Is it weird to eat magnesium?

Amanda Frick:

[Laughs] I think you'd have a hard time eating food if you're worried about trying not to eat magnesium.

Robert Rountree:

It's in a lot of things.

Amanda Frick:

In a lot of things.

Robert Rountree:

Yeah, and in fact, a lot of things that we eat are weird if you want to isolate them. If you took the zinc out and just had a big pile of zinc in front of you, you'd probably say, "Well, why would I want to do that? Why would I want to eat that?" Well, that's true for a lot of things.

Amanda Frick:

Right, that'd be like thinking about eating a metal nugget, right? I mean, same. Why would you eat zinc? It's like a chunk.

Robert Rountree:

It's a chunk of metal. Why would you eat metal? Because our bodies are made of metals, even things... Arsenic is a good example. We need a certain amount of arsenic for ourselves to function properly. So, people hear arsenic, "Oh, that's terrible." But no, a little bit of arsenic is good; it's just that a lot of arsenic is toxic. So that's true for a lot of the metals, the minerals that our bodies are made of.

Amanda Frick:

Especially the trace minerals.

Robert Rountree:

So, why does magnesium bisglycinate promote sleep?

Amanda Frick:

There's multiple reasons why I think you would choose something like magnesium bisglycinate to support restful sleep. One of them, magnesium itself, like we're talking about, you were talking calcium channel blocker or relaxing muscles, helping to relax nerves. A system that's frazzled and overstimulated, [it] can help support that, but bisglycinate is magnesium bound to two glycine molecules.

Glycine's an amino acid by itself that has effects that support restful sleep, restful mind, a balanced mood, because it's supporting inhibitory neurotransmitters in the brain and the nervous system. So you're sort of getting a dual effect of supporting relaxed muscle fibers, supporting relaxed state of mind, and supporting restful sleep. It's like a double hitter.

Robert Rountree:

So the only thing I might add to that is that, and this is a little bit technical, but we know that nerve firing, that firing of neurons is dependent what's called voltage gated channel. OK, I know it's really technical, but neurons are electrical things, like little tiny batteries, and they fire depending on these channels. Magnesium and calcium are involved in those channels, and if there's a deficiency of magnesium, it can cause erratic firing of the nerves. So magnesium generally has a calming effect on the firing of neurons, kind of a long technical way of saying that.

That's actually been shown in animal studies and test tube studies, etc., so it generally calms the nervous system, and I think that has something to do with the sleep promotion. It's not acting like a drug, right? It's not a drug, it just makes the nervous system, again, a little bit more at ease. 

Why doesn't Thorne sell the threonate version of magnesium, magnesium threonate?

Amanda Frick:

Magnesium threonate's gotten a lot of push as far as ability to cross the blood-brain barrier, and so it's positioned a lot for supporting relaxed mood or supporting people with anxious thoughts. But I would posture that first of all, it's really expensive, so to make a product and get the dose that you need to be effective is not very cost-efficient.

There are also some studies showing what types of magnesium are found in brain tissue, so not human studies, but I think saying that threonate is the only magnesium that can get into the brain is probably not accurate, and we feel that adding a magnesium threonate to our suite is not going to accomplish something that we don't already have products to support.

Robert Rountree:

I mean, we already have people telling us that when they take magnesium bisglycinate, for example, that they feel calmer, that it supports nervous system function, right? So if that's the case, then whether you've got a study or not that shows that that magnesium actually made it into the brain is not quite as relevant.

Amanda Frick:

Also from a cost and dose standpoint, then you're getting a more effective combination with the bisglycinate.

Robert Rountree:

Yeah, if somebody is deficient in magnesium, they have to take a lot of the threonate to get their magnesium levels up. 

So Thorne makes a big deal about magnesium stearate as being bad. So here we are having this magnesium discussion, and yet in the background, Thorne is saying, "Well, we have a ‘No List,’ and on that ‘No List’ is something called magnesium stearate." So the writer says, "Clearly the issue is the stearate and not the magnesium, but why is that the issue?"

Amanda Frick:

Well, I think you're right. It's not the magnesium that's an issue, but it's the fact that the compound acts like… So when you're adding magnesium stearate into a powder mixture, which is exactly why it works to help encapsulate powder, is it makes it kind of compact, stick to itself, flows more easily, so you can take powder, run it through machines and get it into a capsule state a lot faster, a lot easier, and it's pretty inexpensive.

So, the problem is that soapy mixture has questionable effects on whether it's inhibiting the absorption of the nutrients you're trying to get into the capsule. So not trying to take the capsule to get magnesium from your magnesium stearate, you want to get whatever the active ingredients are. So we feel that if there's any question that that magnesium stearate could be inhibiting absorption of the active ingredients or the nutrients we're trying to get in, it doesn't belong in your capsule. That's why we talk about it so much, and we're willing to take extra cleaning time, extra costs and a significant impact on our production schedule to make sure we're creating our products without it.

Robert Rountree:

I've had people say, "Well, how much magnesium stearate's in one capsule? How can that be a big deal?" Well, the problem is a lot of people take more than one capsule, right? So, I actually saw a demonstration where a person was say taking five or six different things, and you start mixing all of those things together. Well, maybe you're taking some B vitamins and maybe you're taking a mineral formula, and maybe you're taking an adaptogen, and it adds up very quickly.

So yeah, a little bit of magnesium stearate in one capsule is probably not that big a deal, but if you start taking multiple capsules, then you can get a surprising amount of that magnesium stearate in a very short period of time, and suddenly you're eating something you don't necessarily want to be eating.

Amanda Frick:

Yeah.

Robert Rountree:

All right, folks, that's all the time we have this week. Be sure to leave a comment and subscribe to the show, we really appreciate it. Thanks for listening, and thanks again, Amanda, for podcasting with me.

Amanda Frick:

Thanks, Bob. It was great. Thanks for having me.

Robert Rountree:

Thanks for listening to The Thorne Podcast. Make sure to never miss an episode by subscribing to the show on your podcast app of choice. If you've got a health or wellness question you'd like answered, simply follow our Instagram and shoot a message to @thornehealth. You can also learn more about the topics we discussed by visiting Thorne.com and checking out the latest news, videos and stories on Thorne's Take 5 Daily blog. Once again, thanks for tuning in and don't forget to join us next time for another episode of The Thorne Podcast.