Elemental Magnesium, RDI's and EAR's

5 Minute Read

"How much elemental magnesium is in your product?"

One of our most frequently asked questions is "How much elemental magnesium is in your products?" While this isn’t necessarily a difficult question to answer, we often find the reason you're asking is because you would like to know;

a) how much to apply each day.
b) compare it to oral supplements.
c) compare it to competitors claims.

So we thought we could clear the air and help with some of the confusion.


How much do I need to apply each day?

The simple answer to this question is: as many times as is required to combat the symptoms of your magnesium deficiency. We generally recommend applying a topical magnesium product twice a day, first thing in the morning and last thing at night.

The more complicated answer is addressing how topical magnesium relates to the Recommended Daily Intake (RDI) and Estimated Average Requirement (EAR) provided by the Australian Government's National Health and Medical Research Council.

The rationale behind these figures are based on the US Institute of Medicine study of 1977 into the Dietary Reference Intakes for Magnesium (https://doi.org/10.17226/5776) which is a fantastic source of information about Magnesium.

There is a wealth of information within the report all about magnesium however for the purposes of this blog there are 3 key pieces of information; Bio-availability, Measurements, Hazards.

"Bio-availability for dietary supplements can be defined as the proportion of the administered substance capable of being absorbed and available for use or storage."

Bio-Availability

It can often come as a shock to learn that dietary magnesium in a typical diet has a bio-availability of approximately 50%. Less than half of the magnesium in your diet is actually absorbed and available for use. This figure can get much lower with pharmaceutical tablet and powder forms of magnesium. The bioavailability of dietary magnesium can also depend on the accompanying nutrients such as fiber, phosphorus, calcium, vitamin C and proteins.

It is incredibly difficult to measure how much magnesium is absorbed by the body due to the lack of effective measurement.

Measurements

The typical total body magnesium content is approximately 25g. Around 50-60% of magnesium resides in the bones, the blood serum only contains around 1% (20mg/L). This combined with a number of other factors can make blood serum magnesium tests an unreliable indicator of your body’s magnesium status.

One of the best ways to detect magnesium deficiency is by experiencing the common symptoms such as cramping, headaches, eye twitching & more.

The report relies mostly on balance studies in order to recommend it’s RDI’s and EAR’s for magnesium. These types of tests measure the intake of magnesium (usually through measuring of magnesium within the diet) and then measure the output of magnesium (usually through urine and fecal matter).

A positive balance assumes that the body has ‘enough’ magnesium in the diet, while a negative balance assumes that the body is not getting ‘enough’ magnesium. The report itself critiques a number of these balance studies, as many of them failed to account for all the inputs (hard water containing magnesium for example) as well as all the outputs (sweat for example). These studies also pre-date any form of commercial topical magnesium.

The main problem with these balance studies is that they operate under the assumption that a higher intake would do no good. This is clearly not true of water, no-one recommends “just enough“ to maintain balance. Magnesium is similar to water in this way, the more magnesium your body has, the better it functions.

Which begs the question, how much magnesium is too much?

Hazards

The kidney is the principal organ involved in magnesium homeostasis, therefore when someone has extreme kidney failure, it’s never advised to take magnesium without a doctor's supervision. With health individuals however, the report notes that “Magnesium, when ingested as a naturally occurring substance in foods, has not demonstrated to exert any adverse effects. However, adverse effects of excess magnesium intake have been observed with intakes from nonfood sources such as various magnesium salts used for pharmacological purposes.”

The well known side-effect of taking ‘too much magnesium’ is diarrhea, what isn’t well known is this tends to only be a side effect of tablets and powders. This coincidentally happens to be one of the main benefits of using topical magnesium.

Summary

The common way to determine whether your magnesium levels are deficient is to observe the symptoms such as cramping & eye twitches. The RDI’s and EAR’s refer to the ideal recommended dietary intake for people to maintain balanced magnesium levels.

The kidneys are the main organ that regulates your magnesium levels. Taking too much magnesium in tablet/powder form will often result in diarrhea, however the same effects are not observed with topical or dietary magnesium.

This brings us back to the simple answer; apply as much (or as little) topical magnesium as you like in order to get the intended benefits.

How does topical compare to oral supplements?

Unfortunately comparing elemental magnesium levels in tablets to sprays won’t help you understand which has the better bioavailability or which will better assist you with your symptoms of deficiency. Since RDI’s and EAR’s are based purely on dietary magnesium, we always recommend trying to get your oral magnesium from diet only.

Topical can be a great supplement because you can actually target areas of discomfort with fairly instantaneous results that don’t cause bowel discomfort. You don’t need to use the product for a number of weeks to know if it will work.

That said, we have a lot of happy customers that use both oral and topical magnesium alongside a healthy diet. Ultimately it’s down to understanding your own body and preferences.

How do your products compare to competitors?

Product Amount/Type of Magnesium Elemental Magnesium

Magnesium Pro Spray

160mg/mL Magnesium Chloride Hexahydrate

19mg/mL

Natural Relief Spray

140-180mg/mL Magnesium Chloride Hexahydrate

16-21mg/mL

Our Natural Range Magnesium Oil comes from Australian salt lakes and therefore has deviations per batch. The Magnesium Pro range is lab made and therefore has the same strength in every batch.

While originally making the Pro Range, we closely examined many different types of compounded Magnesiums and the average they all yield is approximately 10% elemental magnesium. We carefully selected Magnesium Chloride Hexahydrate due to it’s high bioavailability and safety profiles.

We're of the opinion that any claims of ~100mg/mL of elemental magnesium is simply unrealistic due to molecular weights. Unfortunately there is little regulation around false claims in the market. A TGA listing is often one of the best ways to identify an authentic amount of magnesium.

We recommend using the right product that works for you and supporting whichever brand aligns with your values.

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