One of the most commonly asked about in clinic is about Magnesium, so we’ve decided to provide you with a run down on the dietary sources, different types & formulations of Magnesium.
Please note: None of this information is designed to replace tailored nutrition or medical advice. You should not add supplements or change your diet without speaking to your healthcare professional first.
What is Magnesium & why do we need it?
Magnesium is an essential mineral in the body – we use it for hundreds of chemical reactions in the body. Whilst can obtain magnesium through your diet, some people, in certain situations may need supplemental magnesium to ensure they meet their daily requirements.
- Muscle & nerve function
- Blood pressure regulation
- Blood glucose regulation
- Detoxification pathways in the liver
- Hormone regulation
- Bone health
- And much more!
The information in this blog is not intended to, nor does it replace the need for medical advice or tailored guidance from a qualified healthcare professional. If supplemental magnesium is something under consideration, you should discuss with your healthcare professional:
- Your current dietary intake
- Any pre-existing health conditions
- Your current or recent medications
- Your current supplementation (if any)
- Digestion & absorption capability
- Potential side effects – alongside health status
- Any sensitivities or allergies
- Your health goals
Any dietary supplements, not just magnesium, should be part of a well-balanced approach to nutrition and lifestyle.
How much Magnesium do we need?
In the UK, the NHS recommendation for magnesium for adults aged 19-64years are:
- 300mg for biological men
- 270mg for biological women
Younger and older individuals will have different requirements. US based, National Institute of Health provides additional guidance on Recommended Dietary Allowances in Table 1 of this fact sheet
which can be a helpful reference point. However, we must also consider nutrient availability in our foods which is impacted by factors including soil health, pesticide use and what a typical diet is made up of. Additionally, when thinking about the amount of any nutrient each individual needs, we must consider factors that may alter the above recommendations:
- Is the amount listed, the minimum needed to avoid a deficiency rather than optimal?
- How much Magnesium is being obtained from the diet?
- Is there an increased need for Magnesium due to a health condition e.g. osteopenia or osteoporosis?
- Is Magnesium absorption altered e.g. due to medication or digestive dysfunction?
Dietary Magnesium Sources
As a rule we can consider fibre containing foods are containing magnesium, but we should also remember tap, mineral and bottled water also contains varying levels of minerals – excessively filtered water may have had minerals removed / reduced.
Magnesium is generally found in the following foods:
- Nuts; brazil, almonds,
- Seeds; pumpkin
- Beans; white, black, lima
- Fish; tuna, halibut, mackerel
- Vegetables; spinach, okra, swiss chard
- Grains; oat bran, brown rice
How much Magnesium is in servings of these food sources?
Factors such as soil nutrient density, locality and processing of food can influence the magnesium content. Additionally you can often see charts stating the amount of magnesium in milligrams (mg) – slightly confusing as the symbol for magnesium is Mg (!) – per 100g of the food item. However, eating 100g of pumpkin seeds is not be a typical serving (25g is more likely) Vs 100g of mackerel which is a typical serving size.
|Serving Size||Food||Magnesium in mg|
|1tbsp = 25g||Roasted pumpkin seeds||156mg|
|1tbsp = 25g||Chia seeds||111mg|
|1tbsp = 25g||Dry roasted almonds||80mg|
|1/2 cup||Boiled spinach||78mg|
|1tbsp = 25g||Dry roasted cashews||74mg|
|1/2 cup||Cooked black beans||60mg|
|1x medium||Baked potato||43mg|
|1/2 cup||Cooked brown rice||42mg|
|85g fillet||Atlantic salmon cooked||26mg|
|1 cup||Dairy milk||24-27mg|
|85g fillet||Halibut cooked||24mg|
|85g||Chicken breast cooked||22mg|
|85g||Ground beef mince cooked||20mg|
|1/2 cup||Cooked white rice||10mg|
Magnesium Types or Forms
If you have ever looked at a bottle of Magnesium supplements you may have seen some of the following names listed. Magnesium is never ‘just’ Magnesium – it must be ‘attached’ to another substance which is why you may have seen some of the types listed below. However, you may also notice some dietary supplements or complexes with bold health claims, these must be viewed with an air of caution. Not least down to dosage, type, formulation, your own biochemistry and genetic make up and how well you digest and absorb any nutrient – dietary or supplemental.
- Sulphate / Sulfate (aka Epsom salts)
The Magnesium types above in bold are the most commonly used or seen in dietary supplements, below we will give a little more explanation on these including benefits and potential side effects. However, be wary of taking bold health claims on any supplements as gospel, reflect on what is marketing Vs hard science.
You should also be aware some magnesium supplements may contain more than one type of magnesium, or be sold with other nutrients in as well. Some medications may interact with magnesium – creating an additive or reductive effect of the medication and therefore impacting symptoms or health condition in some way.
These are two reasons why seeking the guidance of a qualified healthcare professional is crucial.
Magnesium chloride is bound with hydrochloric acid. This form of magnesium may be considered as a tool in supporting blood glucose regulation and may be found in tablet form. In the ‘flake’ form used in a bath, some find it beneficial for supporting sleep quality or may be found in lotions and sprays to apply topically.
- Generally well absorbed in the gut
- Available in topical forms
Potential side effects – may be dose dependent:
- Altered blood pressure or blood glucose
Magnesium citrate is magnesium bound to citric acid. As a supplement Mg citrate is one of the most common forms of magnesium dietary supplements. It is generally well-absorbed and is often used to its potential in promoting relaxation and reducing muscle cramps and tension.
Magnesium citrate increases fluid in the bowel, this process (osmosis) can trigger bowel movements / motility. As such, this form can either be used to support sluggish bowel movements OR for some should be avoided if you already have loose bowel movements.
If you are experiencing sluggish bowels, which may be termed constipation, or other altered bowel movements including loose bowel movements, should first be investigated and assessed before using supplementation.
- Supports bowel regularity
- Reduces muscle cramps and tension
- May help with relaxation and nervous system support
Potential side effects – may be dose dependent:
- Digestive Discomfort – such as cramping
- Diarrhoea – can contribute to loose stools or diarrhoea
Magnesium glycinate (or bisglycinate) is a chelated form of magnesium bound to the amino acid glycine. This type of magnesium is highly absorbable and less likely to cause digestive discomfort that magnesium citrate, which may suit individuals with sensitive stomachs. Often used when supporting the nervous system which may in turn support some types of headache, muscle relaxation, sleep and cognitive function.
- High bioavailability
- Generally well tolerated
- Supportive for the nervous system
Potential side effects:
- Low risk of digestive discomfort, in rare cases, it can cause diarrhea or upset stomach.
Magnesium L-Threonate (or Threonine):
Magnesium L-Threonate is a newer form of magnesium that is gaining attention for its potential cognitive benefits. This form has the unique ability to cross the blood-brain barrier, making it more effective at enhancing brain function. It’s known to improve memory and cognitive performance, making it an intriguing option for those looking to support their mental acuity. This format is generally well-tolerated with fewer side effects.
- Supports cognitive function
- Enhances memory and brain performance
Potential side effects:
- Some individuals may still experience mild digestive discomfort or loose stools – often dose dependent
Magnesium oxide is a lower-cost magnesium supplement that contains a high percentage of elemental magnesium (approx 60%) combined with oxygen. However, it it thought to be relatively low solubility and absorption in comparison to other forms of magnesium. Magnesium oxide is usually found in powder or capsule / tablet form.
This type of magnesium is best suited for individuals with no pre-existing digestive issues.
- May be supportive for heartburn / indigestion for some
Potential side effects – may be dose dependent:
- Digestive discomfort such as cramping or bloating
- Loose stools or Diarrhoea
Magnesium Sulfate (Epsom Salt):
Epsom salt, is also known as magnesium sulfate and also contains oxygen. Typically is used primarily in topical applications like Epsom salt baths, sprays, gels or lotions. Soaking in Epsom salt may help relax muscles, and soothe muscle soreness. It is not intended for oral consumption, Epsom salt is a popular and affordable way to enjoy the benefits of magnesium, especially for those that enjoy a hot bath or foot soak.
- Relaxes muscles
- Soothes soreness
- Over nervous system support
Potential side effects:
- If ingested orally, can have a strong laxative effect, causing diarrhea – not recommended for oral intake.
Dietary supplement delivery methods
What do we mean by delivery methods? Not how to order and have supplements delivered, but how the nutrients are delivered into your body. Why? Because depending on your health status, digestion and absorption capacity but also factors such as swallowing your healthcare professional will likely consider different methods of nutrient delivery IF a dietary supplement is appropriate.
There are several delivery methods to consider, each with its own set of benefits and reasons for use. Understanding these options is crucial because the method selected can impact how your body absorbs and utilises this mineral. You can find some dietary supplement products that contain more than one nutrient either a ‘multivitamin’ or ‘multimineral’ or certain formulations containing nutrients to support a certain system, these may be any of the following methods of delivery.
Tablets and Capsules:
- Convenience: Tablets and capsules are among the most convenient delivery methods. They are easy to take and do not require any preparation.
- Accurate Dosage: They provide a pre-measured dose, ensuring you get a consistent amount of magnesium with each use.
- Portability: Ideal for on-the-go individuals, as they are easily portable and can be taken without water in some circumstances.
- Tasteless: Generally no unpleasant taste, which can be beneficial if you dislike the taste of some powdered forms.
- Customizable Dosage: Magnesium powder allows you to customise your dosage, making it easier to adjust intake according to an individuals specific needs.
- Faster Absorption: Powder tends to be absorbed more easily as no capsule to digest, which can increase absorption speed for some.
- Mixing Options: You can usually mix magnesium powder into various beverages or foods, which may make it more palatable for those who dislike swallowing pills.
- Taste: Some products have an added flavour to make more palatable on their own e.g. citrus fruit
- Slow, Sustained Release: Patches provide a slow, sustained release of nutrients such as magnesium through the skin, which can be beneficial for continuous absorption throughout the day. Also helpful for those that find swallowing capsules,
- Avoiding Digestive Issues: Ideal for those who experience digestive discomfort or are prone to diarrhea with oral supplements.
- Minimized Laxative Effect: Transdermal patches minimize the risk of the laxative effect often associated with oral magnesium supplements.
Topical Creams, Lotions & Sprays:
- Targeted Application: Creams and lotions can be applied directly to specific areas of the body, making them suitable for muscle relaxation and soreness relief.
- Avoiding Digestive Upset: Like transdermal patches, topicals can help individuals sidestep digestive issues.
- External Use: They don’t require ingestion, which can be helpful for those who have trouble swallowing pills.
Usually in the form of a ‘sublingual drop’ i.e. under the tongue OR a spray to the inside of the cheek:
- Quick Absorption: Liquid forms of nutrients are generally absorbed more rapidly, making them a good choice for individuals with an urgent need for magnesium.
- Flavored Options: Some liquid supplements are available in various flavors, which can be more appealing to those who dislike the taste of traditional tablet forms.
- Easy for Children and the Elderly: Liquid magnesium can be easier for children and the elderly to consume.
If you want to find out more about what nutrients you made need to support your health, or confused if the supplements you’re using are right for you then please get in touch.
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