Der große Magnesium-Ratgeber: Eigenschaften, Vorteile, Arten und richtige Einnahme

Magnesium is the fourth most abundant mineral in the human body and one of the most important micronutrients for overall health. It acts as a cofactor in more than 300 biochemical reactions, ranging from cellular energy production (ATP) and protein synthesis to muscle contraction and nervous system regulation.

Despite being present in a wide variety of foods, modern lifestyles, chronic stress and the consumption of ultra-processed foods mean that a significant proportion of the population does not meet the recommended daily intake.

In this comprehensive guide, you will learn what magnesium is good for, its scientifically supported benefits, how to identify low magnesium levels, the differences between its various forms (bisglycinate, citrate and malate), and how to choose the most suitable supplement.

What does magnesium do in the body?

To understand what magnesium does, its main function can be described as acting as the biochemical “spark plug” of our cells.

Without adequate levels of ionised magnesium (Mg2+), enzymes cannot transfer phosphate groups or process glucose, fats and amino acids to convert them into usable energy.

Physiologically, magnesium is mainly distributed throughout the body as follows:

1. Bones and teeth (approximately 60%): forms part of the mineral matrix and works closely with calcium and vitamin D.
2. Muscles and soft tissues (approximately 39%): acts as a calcium antagonist; while calcium triggers muscle contraction, magnesium enables relaxation.
3. Extracellular fluid and blood (approximately 1%): regulates electrolyte balance and the transmission of nerve impulses.

Magnesium benefits recognised by EFSA

Magnesium has several authorised health claims in the European Union, as established in Commission Regulation (EU) No 432/2012.

Its main recognised functions include:

• Contributes to the reduction of tiredness and fatigue: participates in metabolic processes necessary for the normal functioning of the body.
• Contributes to normal energy-yielding metabolism: is involved in numerous reactions related to nutrient utilisation and energy production.
• Contributes to normal muscle function: participates in the physiological processes involved in muscular activity.
• Contributes to the normal functioning of the nervous system: is involved in cellular mechanisms related to nerve transmission.
• Contributes to the maintenance of normal bones and teeth: forms part of the minerals found in bone tissue.
• Contributes to electrolyte balance: helps maintain the balance of minerals and electrolytes in the body.
• Contributes to normal protein synthesis: participates in cellular processes related to protein formation.
• Contributes to normal psychological function: performs physiological functions related to the normal functioning of the body.
• Has a role in the process of cell division: participates in essential mechanisms for cell maintenance and function.

Magnesium for sleep and stress reduction

One of the most common reasons people look for magnesium supplements is to support sleep and nighttime rest.

Magnesium acts as a natural relaxant of the central nervous system:

1. Stimulates GABA receptors: gamma-aminobutyric acid is the brain’s main inhibitory neurotransmitter, responsible for reducing neuronal activity to help initiate sleep.
2. Regulates cortisol levels: helps moderate the hormonal response to physical and psychological stress.
3. Musculoskeletal relaxation: by limiting excessive calcium entry into muscle fibres, it helps prevent physical tension that can make it difficult to fall asleep.

Symptoms of magnesium deficiency: how can you tell if your levels are low?

Magnesium deficiency, also known as hypomagnesaemia when it involves low blood magnesium concentrations, can occur for several reasons, including insufficient intake, certain medical conditions, impaired intestinal absorption or the use of some medications.

One particular characteristic of magnesium is that less than 1% of the body’s total magnesium is found in the blood. Therefore, serum magnesium concentrations do not always accurately reflect the body’s total stores, although they remain a useful tool in clinical assessment.

Possible signs and symptoms of magnesium deficiency include:

• Tiredness and weakness: may occur in the early stages, although these symptoms are non-specific.
• Loss of appetite and nausea: may accompany insufficient magnesium intake or deficiency.
• Muscle cramps, spasms or involuntary contractions: may occur in more significant deficiencies.
• Tingling or changes in sensation: may develop when neuromuscular disturbances are present.
• Heart rhythm disturbances: may occur in severe cases of magnesium deficiency.

For more information about clinical causes and diagnostic tests, read our complete guide to symptoms of magnesium deficiency and how to prevent them.

Types of magnesium: which is best for your needs?

Different forms of magnesium are used in food supplements. Some of the best known include magnesium bisglycinate, citrate, malate, L-threonate and magnesium oxide.

These forms differ mainly in their chemical composition, solubility, elemental magnesium content, absorption characteristics and digestive tolerance.

There is no single form of magnesium that is best for everyone. The choice should take into account the amount of elemental magnesium provided, the characteristics of the formulation, individual tolerance and nutritional needs.

The following comparison table shows the characteristics of the main options available at HSNstore:

For a detailed analysis of each chemical form, read our technical article on types of magnesium and which is best for your needs.

How much magnesium do we need per day?

Magnesium requirements depend on several factors, including age and sex.

The European Food Safety Authority (EFSA) establishes the following adequate intakes for adults:

• Adult men: 350 mg of magnesium per day.
• Adult women: 300 mg of magnesium per day.

These amounts refer to the total daily magnesium intake from food, beverages and, where applicable, food supplements.

They should not be interpreted as the amount of magnesium that needs to be taken through supplements.

During pregnancy and breastfeeding, EFSA maintains the same adequate intakes established for adult women.

For athletes, individual requirements may vary depending on diet, training characteristics and mineral losses. However, participating in sport does not necessarily mean that magnesium supplements are needed, nor does it justify indiscriminately increasing magnesium intake.

How to take magnesium correctly

When taking a magnesium food supplement, it is important to pay attention to the amount of elemental magnesium provided, the recommended dosage and individual digestive tolerance.

What is the best time to take magnesium?

There is no universally optimal time that has been shown to be superior for everyone.

Magnesium can be taken at different times of the day, following the manufacturer’s instructions and taking individual tolerance into account.

Is it better to take magnesium with food or on an empty stomach?

Some people tolerate magnesium supplements well on an empty stomach, while others may experience gastrointestinal discomfort.

Can magnesium be combined with other supplements?

Magnesium may be included in supplements containing other minerals or vitamins. However, it is important to check the total amounts provided to avoid unnecessary duplication.

Magnesium may also interact with certain medications, including some antibiotics and treatments for osteoporosis.

In these cases, it may be necessary to separate doses by several hours, depending on the medication used. If you are taking prescription medication, consult your doctor or pharmacist before introducing a magnesium supplement.

Magnesium safety, contraindications and side effects

Magnesium naturally present in foods is considered safe for healthy individuals when consumed as part of a normal diet.

However, food supplements and certain medicines containing magnesium may cause adverse effects when taken in high amounts or under specific clinical circumstances.

The main precautions include:

• Digestive discomfort: high magnesium intake from supplements may cause diarrhoea, nausea or abdominal discomfort.
• Kidney impairment: people with significantly impaired kidney function may have difficulty eliminating excess magnesium, increasing the risk of hypermagnesaemia.
• Drug interactions: certain antibiotics, bisphosphonates and other medications may interact with magnesium.
• Taking several supplements simultaneously: combining different products containing magnesium may unintentionally increase total magnesium intake.

EFSA has established a tolerable upper intake level of 250 mg per day for magnesium from certain readily dissociable supplemental sources and compounds such as magnesium oxide, in adults, including pregnant and breastfeeding women.

This value refers to additional magnesium from these sources and does not include magnesium naturally present in foods.

It is important to distinguish this limit from the adequate intake values for magnesium, which refer to total consumption of the mineral.

In all cases, the product’s instructions for use and warnings should be followed. People with kidney disease, those taking medication or individuals with specific medical conditions should consult a healthcare professional before taking magnesium supplements.

Studies and References

1. Commission Regulation (EU) No 432/2012 of 16 May 2012 establishing a list of permitted health claims made on foods, other than those referring to the reduction of disease risk and to children’s development and health.
2. EFSA NDA Panel. Scientific Opinion on Dietary Reference Values for magnesium. EFSA Journal. 2015;13(7):4186.
3. EFSA Scientific Committee. Tolerable Upper Intake Levels for Vitamins and Minerals. European Food Safety Authority.
4. National Institutes of Health, Office of Dietary Supplements. Magnesium: Fact Sheet for Health Professionals.
5. de Baaij JHF, Hoenderop JGJ, Bindels RJM. Magnesium in Man: Implications for Health and Disease. Physiological Reviews. 2015;95(1):1-46.
6. Abbasi B, Kimiagar M, Sadeghniiat K, Shirazi MM, Hedayati M, Rashidkhani B. The effect of magnesium supplementation on primary insomnia in elderly: A double-blind placebo-controlled clinical trial. Journal of Research in Medical Sciences. 2012;17(12):1161-1169.
7. Boyle NB, Lawton C, Dye L. The Effects of Magnesium Supplementation on Subjective Anxiety and Stress: A Systematic Review. Nutrients. 2017;9(5):429.

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