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What is Magnesium?

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Magnesium is an essential mineral required for the activation of over 300 enzymatic reactions and biochemical processes in the body¹. Magnesium has diverse functions all around the body, including protein synthesis,² muscle and nerve function,³⁻⁴ energy production,⁵ blood glucose control, and blood pressure regulation¹. 50-60% of the magnesium stored in the body is stored in the bones, with the rest being found in soft tissues⁶.

Recommended Daily Intakes

In the UK, the daily recommended intake of magnesium is 300mg for men, and 270mg for women; however, it is estimated that 10-20% of the UK population has intakes below this⁷.
Increasing intakes of processed and low-nutrient foods, as well as significantly decreased intakes of high-nutrient foods, are thought to contribute to this. Low vitamin D levels are also a risk factor for magnesium deficiency, as vitamin D is necessary for magnesium absorption in the gut⁸. Coffee, alcohol, and high-stress levels can also contribute to increased magnesium excretion, further contributing to deficiency. Chronically low magnesium levels are thought to increase the risk of high blood pressure, cardiovascular disease, type 2 diabetes, and osteoporosis⁹.

What are the signs of Magnesium deficiency?

Magnesium is considered an electrolyte¹⁰, and with less than 1% of total body magnesium being found in circulation, it can be hard to accurately detect deficiencies. As a result, evidence suggests that subclinical magnesium deficiency (deficiency with minimal apparent side effects) is widespread across the UK¹¹.

Subclinical deficiencies can result in gradual changes in physiological or cellular functions¹¹; this type of deficiency can be hard to diagnose or detect but can subsequently result in long-term chronic diseases. As magnesium deficiency can often go unnoticed, there are several symptoms that could be early, non-specific signs of deficiency, such as anxiety, depression, sleep disorders, headache, and constipation, which may be harder to correlate with magnesium deficiency¹¹.

Additionally, if your magnesium levels are low long-term, or you suffer from other health conditions which affect magnesium levels, you may be at greater risk.

The more obvious signs of Magnesium deficiency can include¹²:

  • Loss of appetite
  • Nausea and vomiting
  • Weakness & fatigue
  • Shaking pins and needles
  • Muscle spasms
  • Hyperexcitability
  • Abnormal heart rhythms

Thankfully, magnesium intake can be supported by increasing your intake of magnesium-rich foods, or taking a dietary supplement. Foods with great levels of magnesium include kale, spinach, wholegrains, legumes, seeds, nuts, avocados, bananas, and dark chocolate.

What is Magnesium good for?


Magnesium is an essential mineral for the maintenance of healthy bones. An adequate supply of magnesium is needed to support calcium absorption and bone crystal formation¹³. Magnesium is also believed to improve vitamin D bioavailability and activation, which also contributes to increased calcium absorption into the bones¹⁴. Research has shown that having decreased levels of circulating magnesium is associated with an increased risk of fracture in men¹⁵, and lower bone mineral density in women¹⁶.


Sleep is dependent on a good supply of magnesium: in human cells, levels of magnesium rise and fall in a daily cycle, and may play a role in maintaining circadian rhythm¹⁷. Magnesium is essential for the production and activation of serotonin, which is converted to melatonin at night and contributes to helping you fall asleep¹⁷. If low serotonin and melatonin levels are affecting sleep, taking a magnesium supplement may be efficient to support this.

Research has shown that magnesium supplements may improve sleep efficiency, and sleep time, and reduce early morning waking, with long-term benefits including reducing daytime sleepiness¹⁸⁻¹⁹⁻²⁰.

Exercise & Energy Production

Magnesium’s role as an electrolyte is considered to be particularly important for muscle function and nerve transmission, and may contribute to relaxing aches, pains, and muscle spasms after intense exercise²¹. Magnesium supply is rapidly used up during periods of stress and when energy demands are high, meaning that supplementing when performing intense exercise is essential²².

Magnesium is also essential for the activation of ATP (Adenosine Triphosphate), the main source of energy required by every cell in the body²³. Magnesium also supports the transfer of glucose in food into body cells²³, key to efficient energy production during exercise.

Heart Health

Magnesium plays a role in the biochemical reactions in the heart muscle which generate the heartbeat²⁴. Like all muscles throughout the body, the heart muscle relies on interactions with calcium and magnesium in order to contract and relax. Whilst calcium stimulates the muscle fibres, magnesium has the opposite effect, allowing the muscle fibres to relax²⁵. Having enough magnesium is essential to ensure your heart can maintain its proper function.

Magnesium also plays a role in the sodium-potassium pump: an enzymatic reaction involved in generating electrical impulses and nerve signals essential for muscle contraction and movement throughout the body²⁶.

Magnesium may help to reduce blood pressure by increasing the production of nitric oxide²⁷, a signalling molecule which contributes to the relaxation of blood vessels, helping to reduce the effects of endothelial dysfunction and promoting healthy vasodilation²⁸. These processes facilitate the healthy functioning of blood vessels around the body, helping to reduce and maintain blood pressure.

Why are different forms of Magnesium important?

Magnesium is very chemically reactive, and therefore needs to be bound to something else to ensure it is stable enough to consume. Depending on why you want to take a magnesium supplement, considering the different forms of magnesium can ensure you take the most suitable form.

Chelated Magnesium - what is it?

Chelation is a binding process which combines minerals like magnesium with organic compounds, improving the bioavailability and stability of the nutrient. The most common chelated magnesium supplements include citrate, glycinate, chloride, malate, taurate, oxide, and sulphate. Chelated minerals bypass the digestive process, allowing them to be effectively transported across the intestinal wall, and used efficiently around the body²⁹. Increased stability also reduces the chance for negative reactions with fat-soluble vitamins and other minerals, increasing absorption rate and effectiveness²⁹.

Feel’s forms of Magnesium

Magnesium Citrate

Magnesium citrate is formed of magnesium bound to citric acid. It is considered highly absorbable, and research has found magnesium citrate to have increased bioavailability over both magnesium citrate and magnesium oxide for both acute and chronic supplementation periods³⁰. Magnesium citrate is also considered a ‘gentle’ compound; easy in the stomach and digestive tract.

Magnesium has been shown to have great benefits for energy production, muscle and nerve function, and cardiovascular and bone health²⁻³⁻⁴⁻⁵⁻, which is why we’ve included magnesium citrate in Feel Multivitamin.

Magnesium Bisglycinate

Magnesium bisglycinate is formed from elemental magnesium bound to the amino acid glycine. Research has shown that due to the presence of glycine, magnesium bisglycinate may have a calming effect on the brain and contribute to a better night’s sleep³¹. Magnesium bisglycinate also supports the body in producing the calming neurotransmitter GABA, which helps to support relaxed mood³¹.

Because of magnesium's important role in sleep, and the calming benefits of glycine, we chose to include 200mg of magnesium bisglycinate in Feel Sleep.

Aquamin: Magnesium

Aquamin magnesium is derived from a natural mineral source: seawater. Aquamin magnesium is a multi-mineral complex with a highly bioavailable source of marine magnesium, with an additional 72 trace minerals which act synergistically with the enriched magnesium content³².

Marine-derived magnesium has been shown to be significantly more bioavailable than other forms of magnesium found in supplements, with specific benefits including bone and muscle health, energy production, and nervous system function³³.

Aquamin’s source of magnesium has shown great results for bone health, which is why we’ve included 328mg of Aquamin Magnesium in Feel Bones.

Beverley Shergold, BANT registered Nutritionist,
BANT registered Nutritionist

 Beverley Shergold, BANT registered Nutritionist

Beverley is a BANT registered Nutritionist and a CNHC registered Nutritional Therapist. She has worked in the nutrition industry since qualifying over 15 years ago and is an experienced educator, currently acting as Programme Leader for a BSc (Hons) degree in Nutrition & Lifestyle Medicine. Alongside her work in nutrition education, Beverley also consults with organisations on nutrition and wellbeing and offers private consultations. She has a special interest in the influence of nutrition and lifestyle on the immune system and in oral health.


¹ https://www.hindawi.com/journals/ije/2018/9041694/
² Magnesium contributes to normal protein synthesis
³ Magnesium contributes to normal muscle function
⁴ Magnesium contributes to normal functioning of the nervous system
⁵ Magnesium contributes to normal energy-yielding metabolism
⁶ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3775240/
⁷ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6060686/
⁸ https://pubmed.ncbi.nlm.nih.gov/11425281/
⁹ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5690358/
¹⁰ Magnesium contributes to electrolyte balance
¹¹ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5786912/
¹² https://pubmed.ncbi.nlm.nih.gov/26404370/
¹³ https://www.degruyter.com/document/doi/10.1515/cclm-2012-0868/html
¹⁴ https://www.degruyter.com/document/doi/10.7556/jaoa.2018.037/html
¹⁵ https://link.springer.com/article/10.1007/s10654-017-0242-2
¹⁶ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3953885/
¹⁷ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6910806/
¹⁸ https://pubmed.ncbi.nlm.nih.gov/35184264/
¹⁹ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3703169/
²⁰ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6212970/
²¹ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6524065/
²² https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5622706/
²³ https://www.sciencedirect.com/science/article/pii/B978012375083900177X
²⁴ https://www.ackdjournal.org/article/S1548-5595(18)30040-5/fulltext
²⁵ https://pubmed.ncbi.nlm.nih.gov/7286246/
²⁶ https://pubmed.ncbi.nlm.nih.gov/28124894/
²⁷ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5338151/
²⁸ https://onlinelibrary.wiley.com/doi/full/10.1111/j.1751-7176.2011.00538.x
²⁹ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5652077/
³⁰ https://pubmed.ncbi.nlm.nih.gov/14596323/
³¹ https://www.researchgate.net/publication/221794543_New_Therapeutic_Strategy_for_Amino_Acid_Medicine_Glycine_Improves_the_Quality_of_Sleep
³² https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6073474/
³³ https://www.prinovaglobal.com/content/dam/prinova/documents/whitepapers/PRN-Aquamin_Bonehealth_RoW_EN_WP-D01.pdf

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WeAreFeel Nutrition Team - All content provided on our blog is created exclusively for our readers by our research and nutrition team. We try to provide as much scientific backing as possible with references to support any claims made.
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