Q: Are different forms of magnesium better for different ailments?
A: It's a bit misleading to think of one form of magnesium being better for a certain ailment. While there is a basis for this belief, it's not quite this simple. To understand this fully, a bit of background on magnesium is needed.
In order to be utilized by the body, magnesium must be bound to a carrier. This is true for all minerals; think of putting a rusty nail into a glass of water and drinking it to get your iron - it wouldn't work because there is nothing for the iron to bind to. Magnesium citrate is a magnesium molecule that is bound to citric acid; magnesium glycinate (also known bisglycinate) is magnesium that is bound to the amino acid glycine; magnesium oxide is a salt that combines magnesium and oxygen; magnesium malate is magnesium bound to malic acid, etc.
When someone talks about a certain form of magnesium being better for a specific ailment, this is the logic they are using - malic acid is good for energy, therefore magnesium malate is best for those with chronic fatigue syndrome; glycine has been shown helpful in sleep studies, therefore magnesium bisglycinate is best for sleep and relaxation, and so on. While there is some truth to this, it is more important to have a form of magnesium that is highly absorbable - if your body is not absorbing your magnesium it won't do you much good. Different forms of magnesium are absorbed at different rates.
What to Look For Instead
One of the most bioavailable forms of magnesium is an ionic magnesium citrate like MAG365, which is almost completely absorbed by the body. Because it is ionic, it doesn't need your stomach acid to digest it, which is what gives it a unique advantage over other formulations. Compare this to magnesium oxide, which has a 4% absorption rate and you start to get a picture of why quality matters more than the form.
Magnesium oxide is the only form of magnesium that has been studied so admittedly there is a bit of guesswork on absorption rates, however the science behind formulations is clear: proper forms will always have a higher absorption rate. This logic would apply to a magnesium bisglycinate formulation such as PrizMAG as it is in a chelated form. It is not ionic, but your gastrointestinal tract can readily absorb the glycine amino acids it is attached to, which allows for easy absorption directly into the cells.
Not All Magnesium Forms Are Created Equally
Most magnesium citrate is not ionic and has a reputation as a laxative - this shows that the body is not utilizing it, but flushing out it through the bowels unassimilated. When comparing to ionic magnesium citrate, this name is misleading as it has nearly the same name but the scientific properties of the two are very different. It is important to note that if you take too much of a quality magnesium source you will also experience this side effect. This doesn't mean your body didn't absorb it - it just means that you took more than your body can utilize at one time. Building up a dosage slowly can mitigate this problem, as can taking it in divided doses or slowly sipping it throughout the day. Sometimes it takes your body a while to adjust to taking supplemental magnesium.
What We Manufacture and Why
We currently focus on two types of magnesium: ionic magnesium citrate and chelated magnesium bisglycinate. The reason we have focused on these types of magnesium is because we believe they are the most absorbable. After formulating MAG365 - which we believe to be the most bioavailable to the body - we found that some people wanted a capsule form.
Our research led us to launch PrizMAG, which is the only pure bisglycinate on the market, free from fillers, binders, excipients, and most importantly magnesium oxide; many magnesium bisglycinate products are buffered with magnesium oxide even though the label doesn't disclose this. We believe that this is the best capsule form of magnesium, and has a high absorption rate, only surpassed by ionic magnesium citrate.
The good news is that any high quality magnesium supplement will help with magnesium deficiency symptoms, but we encourage you to focus on quality over hype. And if you really want to enjoy the secondary benefits a particular form might give, you can always take that substance as a separate supplement (ie. malic acid for energy).
Firoz M, Graber M. (2001. Bioavailability of US Commercial Preparations. Dec; 14 (4): 257-62. (https://pubmed.ncbi.nlm.nih.gov/11794633/).