Should You Take Multiple Types of Magnesium?

This can make it tricky to know which one to take. Is there really that much of a difference? And should you be taking more than one type?

Below we break down the unique properties of different magnesium types, including how well your body uses and absorbs them, and how they differ in their potential benefits. And, we address the question of whether you should be supplementing with more than just one type!

How Do Various Types of Magnesium Benefit the Body Differently?

To discuss differences in absorption, we’ll introduce a concept called bioavailability. Various types of magnesium supplements have different bioavailability to different extents. 

What Is Magnesium Bioavailability?

Bioavailability is a measure of how much of something is absorbed and utilized by your body. This is a good question to ask because when we are thinking about taking a supplement or trying to increase magnesium levels through diet, we want to know how much is actually getting to where we need it.

And, it turns out that bioavailability can vary greatly depending on how much magnesium you need. Your body has mechanisms that regulate magnesium absorption based on your current magnesium status. While we are not entirely sure how it does this, this regulation means that you could be absorbing anywhere between 25-75% of what you ingest. This is a huge range, right?

For example, if you have sufficient magnesium stores, you are likely going to absorb about 25% of dietary magnesium. In contrast, if you are deficient you can absorb up to 75%. It is important to know that most of the magnesium you take in goes into storage – bones, muscles, and other issues. In fact, only 1% of all the magnesium in your body is actually in the water portion of your blood (serum) .

Besides your current status, there are other internal factors that might impact magnesium absorption:

• Age: as you get older, your body becomes less efficient at taking up nutrients, including magnesium.

• Kidney function: your kidneys play a big role in regulating magnesium levels. In fact, they filter about 2,400 mg of magnesium per day, removing 5% into urine. This means that 95% is reabsorbed! But, if you have issues with your kidneys, they may be less efficient at these reabsorption processes, and change how much your body retains and excretes.
• Other health factors: such as blood sugar control, stress, and more.

Extent of Bioavailability

Now, there are multiple levels of bioavailability because simply because it gets absorbed in the gut doesn’t mean it reaches your brain. You can have gut bioavailability, cellular bioavailability, and tissue-specific bioavailability, which are all different.  

Let’s look at a few types of magnesium bioavailability. 

1) Gut Bioavailability (i.e. increasing serum magnesium)

Gut bioavailability means how much magnesium from diet or supplements is absorbed through your gut and into the bloodstream as opposed to getting eliminated through feces.

When you consume magnesium, most of it gets absorbed in your small intestine and some in your colon. After ingestion, it takes about 1 hour for absorption to start occurring, and peaks 2-2.5 hours after. While individual factors can play a role in how much you absorb, generally we understand magnesium to have about 30% bioavailability. 

Here is an example: Say you consume 360 mg of magnesium. You lose approximately 160 mg in feces and 100 mg in kidney excretion. This leaves about 100 mg to be taken up into the bloodstream. As we learned about, the kidneys play a big role here, filtering and reabsorbing magnesium to ensure a healthy balance.

2) Cellular Bioavailability (i.e. increasing red blood cell magnesium)

Cellular bioavailability means the amount of magnesium actually taken up and used by the cells in your body from the bloodstream versus getting excreted in the urine. 

Various cell types can absorb magnesium differently, so it’s possible that cellular bioavailability varies by tissue. However, a good test for cellular magnesium is the red blood cell magnesium test, which measures how well your magnesium gets absorbed by red blood cells. Because this number is less impacted by acute changes, it can be a more accurate reflection of magnesium status.

3) Brain Bioavailability (i.e. crossing the BBB)

Finally, when we talk about brain bioavailability of magnesium, we want to know how much effectively crosses the blood-brain barrier, to be used by brain cells. While we generally can’t directly measure this value in humans, researchers use indirect methods to see how well magnesium can cross through the blood-brain barrier to carry out its functions.

Why do we care about this? Well, magnesium is really important for the function of your brain. And, magnesium levels are higher in the brain than in the blood with your body working hard to keep this balance.

Generally, if your magnesium cannot be absorbed through the gut, it will also not reach your cells, organs, and brain. So, low gut bioavailability also means low cellular and organ bioavailability. However, in order to have high cellular and organ bioavailability, you need to have a high gut bioavailability. 

Before we dive into the different types of magnesium, let’s look at some external factors that can impact magnesium absorption:

Decrease absorption:	Increase absorption:
Single, high dose Taking with high amounts of other minerals (phosphorous, iron, copper, manganese, and zinc) Consuming with oxalic acid (like spinach) Consuming with phytic acid (cereals, nuts, seeds, and legumes) Consuming with certain fibers (wheat bran, cellulose, lignin)	Taking with a meal Taking alongside fermented foods, starch, inulin, and other low or indigestible carbohydrates Spreading out doses throughout the day

Distinct Tissue Bioavailability and Benefits of Different Magnesium

There are a wide array of magnesium types on the market, making it challenging to know which ones you should be taking. Each type differs slightly in terms of absorption rates and bioavailability to different tissue types.

While many clinical studies have compared blood levels of magnesium after various magnesium supplements, it’s not very ethical to feed magnesium supplements to humans and biopsy all their tissues to measure their tissue magnesium bioavailability. 

Therefore, most tissue bioavailability studies are done in rodents and provide relatively informative data that may be applicable to humans. For example, in rodents, organic acid forms of magnesium like malate and acetyl taurate have better tissue bioavailability than oxide. 

There is also a limited number of clinical and animal studies that use radioactive magnesium. As a result, despite limited clinical evidence, most clinicians widely accept that organic forms of magnesium have better gut and tissue bioavailability than inorganic forms.

Let’s break down what some of those might be for each type of magnesium on the market:

1) Magnesium Oxide

Magnesium oxide is magnesium combined with oxygen. It has lower gut bioavailability compared to other forms of magnesium. In a small clinical study, only about 4% of magnesium oxide is absorbed through the gut. 

However, it has a good ratio of magnesium content by weight. Know that while this form can seem like a good option to increase magnesium levels because of its higher elemental magnesium content, its low absorption can also lead to gastrointestinal discomfort and a potent laxative effect.

When made into effervescent tablets, gut absorption can be boosted up to around 10% by improving its water solubility. Because of its poor gut bioavailability, it is not very good at increasing magnesium levels, even though most magnesium clinical trials use magnesium oxide. Instead, it is often used for helping digestive issues like heartburn, indigestion, and constipation.

2) Magnesium Sulfate

Also known as Epsom salts, magnesium sulfate is not generally a component of supplements but is instead used to help ease muscle tension when added to baths. Because it is topical, absorption rates are low – we do not absorb nearly as much magnesium through the skin compared to the digestive tract . It can also be used as a laxative as it has poor gut bioavailability and can pull water into the gut.

3)  Magnesium Chloride

Magnesium chloride consists of magnesium combined with chlorine. Chlorine is unique because it dissociates from magnesium easily and can rapidly bind with other elements to form a salt. This type tends to be more readily absorbed compared to magnesium sulfate and magnesium oxide.

Magnesium chloride can support healthy blood sugar control and can raise blood magnesium levels by more than 13%, suggesting that it has some gut and pancreas bioavailability.

4) Magnesium Malate

This form combines magnesium with malic acid, a compound that can be found in apples. In rats, magnesium malate is absorbed quickly, raising blood magnesium levels after 4 hours with levels peaking after 8 hours. In this study, magnesium malate raised muscle magnesium more than other types, although this was not statistically significant from other types of magnesium.

5) Magnesium Glycinate (Bisglycinate)

Magnesium glycinate has emerged as one of the more popular forms for supplementation. It combines magnesium with two glycines, an amino acid that has an inhibitory effect on the brain. Glycine also has chelating properties, which can help bind and transport magnesium molecules in the body. 

In a study in people without the end part of their small intestine, magnesium bisglycinate could be absorbed. So, the authors concluded that magnesium bisglycinate could be absorbed like dipeptides. This means magnesium bisglycinate is less likely to cause digestive distress and could be absorbed even despite suboptimal stomach acid or digestion. Other amino acid chelates of magnesium such as threonate and aspartate may also be absorbed in the same manner. 

6) Magnesium Threonate

Magnesium threonate combines magnesium with a naturally occurring amino acid, L-threonine. This form has been one of the most studied when it comes to increasing magnesium concentrations in the brain.

This form seems to have higher bioavailability, especially in crossing the blood-brain barrier compared to other magnesium supplements. Also, a few clinical trials confirm its benefits in brain and cognitive health. As such, it is often promoted for potential cognitive benefits like supporting brain health and function.

7) Magnesium Aspartate

Magnesium aspartate is magnesium combined with the amino acid aspartate. This form is thought to be easier for the body to absorb compared to magnesium oxide or magnesium citrate. Some research shows it can be helpful for muscle fatigue and hyperactivity. Magnesium aspartate is also a key part of a popular sleep supplement in bodybuilders called ZMA or Zinc, Magnesium, and Aspartate. 

8) Magnesium Citrate

Magnesium citrate is magnesium combined with citric acid, a natural component that is found in citrus fruits. In a clinical study, subjects took ~600 mg elemental magnesium of citrate vs oxide and measured their urine magnesium excretion at 2 and 4 hours afterward. 

The citrate group had about 37 times higher urinary magnesium excretion than the oxide group at the four-hour mark. This is likely because the citrate makes it more soluble in water and better absorbed through the gut.

Even still, it has poor absorption and some laxative effects compared to some of the other forms of magnesium. It is also a very affordable option compared to some other forms.

9) Magnesium Taurate

This form combines magnesium with the amino acid taurine. It is commonly used for heart health, with research showing it can help keep blood pressure in check. In a systematic analysis, magnesium taurate was one of the best absorbed and tends to accumulate in the brain with lower levels in the blood and muscle.

10) Magnesium Acetyltaurate

Magnesium acetyltaurate combines magnesium with taurine and an acetyl group. Magnesium acetyl taurate can cross the blood-brain barrier in good amounts, but accumulate less in other tissues. Therefore, it’s the most beneficial for the brain.

11) Magnesium Chelate

Magnesium chelate is a form of magnesium where magnesium is bound to an organic chelating agent. These tend to be amino acids or other substances such as sugars or starches. One study showed good absorption, with a comparable uptake to magnesium citrate.

12) Magnesium Orotate

This type pairs magnesium with orotic acid, which seems to help transport magnesium into cells and act as an antioxidant. Clinical trials show that it has multiple heart health benefits, suggesting that it has high bioavailability to heart tissues. It might help protect against tissue damage, and has good kinetics once it is in systemic circulation. But, we still do not know how well we are able to take this form up from the digestive tract.

13) Magnesium Lactate

Magnesium lactate combines magnesium with lactic acid, designed to increase its absorption. This is because this combination can improve how soluble the supplement is in water.

In one study, results showed that the caplets had a bioavailability of around 20% when taken on an empty stomach and about 12% when taken with food. They also found that bioavailability was higher when taken with food compared to fasting.

14) SucrosomialⓇ magnesium

SucrosomialⓇ magnesium is magnesium oxide embedded in phospholipids and sucrose esters to improve absorption. In a clinical trial of 10 healthy subjects, SucrosomialⓇ magnesium had better gut and red blood cell bioavailability than magnesium oxide and bisglycinate. It also is less likely to cause digestive upset or loose stools.

Do You Need Multiple Forms of Magnesium?

As we learned above, certain forms of magnesium can offer different benefits compared to others. Even the well-absorbed ones have different cellular and tissue bioavailability. When choosing which ones to take, you need to keep your unique goals in mind. 

There can be positives with combining different forms, broadening the range of benefits. Since each type offers its own advantages and disadvantages, you can tailor your approach to suit your own needs.

Combining different forms can also enhance absorption and utilization by your body. While some are absorbed better, others release magnesium slowly over time. Some gravitate towards the brain, others towards the heart, or muscles. Therefore, mixing forms can optimize magnesium’s effectiveness and availability for the body.

But, some magnesium types might have actions you don’t want. For instance, if you already tend towards loose stools, it is probably best to avoid taking a magnesium form with strong laxative properties. And, certain magnesium forms can interfere with medications, so it is always best to double-check the forms that are included in supplements.

Although mixing magnesium forms is generally safe, it’s crucial to monitor your total intake. If you get diarrhea, cramps, and stomach discomfort, adjust your dosage carefully to avoid these issues.

Should You Take Multiple Types of Magnesium?

This can really depend on what you are hoping to accomplish with supplementation. Do you want to address a specific need that maybe one form has been more studied than another? If so, it might be good to stick to that particular magnesium type.

Otherwise, if you are just looking to improve your overall magnesium status, a full-spectrum magnesium can be helpful. Because various magnesium forms have different absorption and bioavailability rates, a combo product can ensure that you are taking up enough and maximize its efficacy throughout your body.

Conclusion
As we’ve learned, different types of magnesium have different bioavailability both through the gut and in different tissues. Therefore, each can have unique benefits compared to other types. Regardless, making sure you have enough and diverse types of magnesium is important for your health.

This is why we have formulated Magnesium Breakthrough, combining the magnesium types with the most evidence to back up their use. This ensures you are maximizing absorption and getting the most out of your supplement routine. Whether you want to balance stress responses, get to sleep faster, optimize your hormones and metabolism, or build strong bones, Magnesium Breakthrough can be the tool you need to get started.