Magnesium Dosage – How Much Magnesium Should I Take

This article will explain everything you need to know about how much magnesium you should take.  We also explain how and when to take magnesium for best results.

The correct magnesium dosage depends on many factors, including:

• Are you male or female? 
• Your age
• Which type of magnesium are you taking?
• Is the magnesium buffered?
• What is the main reason you are taking magnesium?
• Are you referring to “elemental magnesium”?

Let’s start with an overview of the Recommended Dietary Allowance (RDA) and the Upper Limits (UL) of magnesium per day.

RDA – Recommended Dietary Allowance:

This refers to the recommended daily intake of elemental magnesium from a combination of diet and supplements.

UL – Upper Limit:

This refers to the safe daily upper limit of elemental magnesium from supplements alone.

***NOTE:  You may have noticed that the safe upper limit (UL) is often showing a lower number than the recommended dietary allowance (RDA).  This is because the RDA is referring to total magnesium from diet and supplements, and the UL is referring to magnesium from supplements alone. 

Table 1: Recommended Dietary Allowances (RDAs) for Magnesium

Age	Male	Female	Pregnancy	Lactation
Birth to 6 months	30 mg*	30 mg*
7–12 months	75 mg*	75 mg*
1–3 years	80 mg	80 mg
4–8 years	130 mg	130 mg
9–13 years	240 mg	240 mg
14–18 years	410 mg	360 mg	400 mg	360 mg
19–30 years	400 mg	310 mg	350 mg	310 mg
31–50 years	420 mg	320 mg	360 mg	320 mg
51+ years	420 mg	320 mg

*Adequate Intake (AI)

Table 3: Tolerable Upper Intake Levels (ULs) for Supplemental Magnesium

Age	Male	Female	Pregnant	Lactating
Birth to 12 months	None established	None established
1–3 years	65 mg	65 mg
4–8 years	110 mg	110 mg
9–18 years	350 mg	350 mg	350 mg	350 mg
19+ years	350 mg	350 mg	350 mg	350 mg

Important Insight:

You may have noticed that we’re using the term “elemental magnesium” and not just “magnesium”.  This is essential to understand, even though most respected health websites don’t even mention it.

Magnesium supplements are never pure magnesium because pure magnesium is just a metal, which humans obviously can’t ingest.  Magnesium for humans needs to be in some edible form like magnesium bisglycinate (glycinate), magnesium citrate, magnesium oxide, etc.  

Elemental magnesium refers to just the magnesium component of these compounds, if you were to strip away the glycinate, citrate, or oxide parts of the molecules.  

We have a very popular article on which explains elemental magnesium in detail.

What type of magnesium are you taking?

This is perhaps the most important and most overlooked question with regard to magnesium dosing.  

The form magnesium is in matters immensely.  What matters is not only how much magnesium you take, but also how much magnesium actually absorbs.  

This is why talking about “magnesium” in general, without specifying which type of magnesium you are taking, actually doesn’t make a lot of sense.

Most magnesium supplements have very low bioavailability.  This means they absorb very poorly in the body.  Magnesium oxide, the cheapest and most popular magnesium supplement, absorbs at a rate of only about 4%.  

Non-buffered magnesium bisglycinate has the highest absorption of any magnesium supplement.

What is non-buffered magnesium?

Buffered magnesium means that another form of magnesium has been added to it.  Most magnesium bisglycinate supplements are buffered, even though the supplement label won’t say this.  These supplements are usually buffered with high amounts of magnesium oxide, which has the poorest absorption.

This is why we recommend non-buffered magnesium bisglycinate

Another major problem with taking a magnesium supplement that doesn’t absorb well (besides the problem of not getting the magnesium you need), is that it will cause stomach upset and diarrhea.  Learn more about the form of magnesium that won’t cause diarrhea. 

How much magnesium should you take from magnesium bisglycinate (non-buffered)?

Non buffered magnesium bisglycinate (which is the same thing as non buffered magnesium glycinate) has the highest bioavailability of any type of magnesium.

Our capsules are 500 mg of magnesium bisglycinate each, which is 50 mg of elemental magnesium.  The rest of the 500 mg is the “glycinate” part of the molecule.

Because they absorb so well, many people feel great after only 1-2 capsules per day, which is only 50 to 100 mg of elemental magnesium.  

Some people require even more magnesium, and they can safely take up to 6 of our capsules per day.  This is 300 mg of elemental magnesium.

It is best to start with 1-2 capsules per day, and slowly work up if you feel you need more magnesium.  Because these are non buffered, you won’t experience any nausea, diarrhea, or other gastrointestinal side effects.  

There are many other forms of supplemental magnesium:

• Magnesium Oxide
• Magnesium Citrate
• Magnesium Taurate
• Magnesium Chloride
• Magnesium Lactate
• Magnesium Malate
• Magnesium L Threonate
• Magnesium Orotate

If you are taking any of these forms, you should make sure you stay under the UL (Upper Limit) per day based on the table above, or check with your healthcare provider.

Why are you taking magnesium supplements?

The reason you are taking magnesium supplements can affect the amount you should take. 

There are many reasons you may wish to take magnesium supplements.  

Some potential reasons are:

• To reverse magnesium deficiency
• To help with relaxation and sleep
• To help with migraine
• To reduce leg cramps
• To reduce constipation 

Note:  If you are taking magnesium for the purpose of reducing constipation, you should actually take the form with the worst bioavailability.  This is magnesium oxide.  The side effect of magnesium oxide is making you run to the bathroom, hence reducing constipation.  It isn’t the magnesium that is working, it is actually the fact that the magnesium isn’t staying in your body that is producing the results.  For all other reasons of taking magnesium, you should take a magnesium supplement that absorbs very well.

Some people, for example, take magnesium to help them sleep.  If they are able to sleep well with only 50 mg of elemental magnesium per day, then they may choose to not take any more magnesium.  Other people may need closer to the Upper Limit (UL) per day to get the desired result.  We have seen similar results with people taking magnesium to reduce migraines or leg cramps.  The amount of magnesium that works for a specific condition varies quite a bit from person to person.

Remember to always stay within the safe recommended limits of magnesium intake unless your healthcare provider recommends otherwise. 

Should I take magnesium in the morning or at night?

Customers are always asking us, “When should I take magnesium?”.  “Can I take it in doses spread out during the day, or is it best to take it all at once?”

This largely comes down to personal preference.  If you are taking it to help you sleep, then you can take it before bed.  It will also help you reduce leg cramps at night.  

Some experts recommend taking magnesium with meals because it can help reduce potential side effects like diarrhea.  

We don’t make that recommendation because if you are taking non-buffered magnesium bisglycinate, then diarrhea won’t be an issue for you.  Remember, non-buffered is key.

You can either space your magnesium supplements throughout the day, or take them all at once, whichever feels better for you.

Is it ok to take magnesium supplements every day?

Yes.  If you are taking magnesium supplements at safe dosages (mentioned above) then you can safely take them every day.  If you have any concerns about your unique health situation, you should speak with your healthcare provider.

Should I take magnesium with food, or on an empty stomach?

This is also a matter of personal preference.  As mentioned above, some experts recommend taking magnesium with food in order to prevent any side effects like diarrhea.  This is reasonable advice if you are taking the typical magnesium supplements you will generally find.  

Since we recommend non-buffered magnesium bisglycinate supplements, you really have the luxury of taking them with or without, because side effects like diarrhea are not an issue.  

Some foods inhibit the absorption of magnesium, so you may wish to take it on an empty stomach in that case.  In a good form, magnesium is quite gentle on the stomach.

What inhibits the absorption of magnesium?

Many nutrients can interfere with, and inhibit the absorption of magnesium.  

Here is a list of nutrients that inhibit magnesium absorption:

• Calcium
• Phytates
• Zinc at very high doses 
• Potassium
• Oxalate
• Proteins
• High doses of vitamin D

What decreases the amount of magnesium in the body?

A lot of things in our lives actually decrease the amount of magnesium we have in our body.  This makes our magnesium intake needs greater.

Things that decrease the amount of magnesium in our body:

• Coffee (caffeine)
• Stress
• Alcohol
• Excess sweating
• Certain medications 
• Nicotine