Nowadays it is known that magnesium is not only important for athletes, but plays an indispensable role in human life. Therefore, care should be taken to ensure an adequate supply of this element. The connection between magnesium and the microbiome is particularly noteworthy, as this relationship has far-reaching effects on our health – from intestinal function to mental well-being.
The super substance magnesium
Magnesium is one of the most versatile and important minerals in the human body. It is involved in over 300 biochemical reactions and plays a central role in almost all essential bodily functions. From energy production in the cells to the regulation of the nervous system and muscle activity – magnesium is essential for good health. At the same time, it acts as a natural antagonist of calcium, helping to relax muscles and stabilize nerve impulses.
Magnesium dominates in the bones
The magnesium measured in the laboratory during blood analysis is not a sufficient indicator of magnesium status, as it only accounts for 1% of the total magnesium in the body.
50-60% of magnesium is stored in the bones. A third of this serves as a dynamic store and can be quickly released into the bloodstream if required.
20-30 % is stored in the muscles. The rest is found in other soft tissues such as the liver, heart and kidneys.
Of the magnesium found in the blood, 55-70% is ionized, i.e. it is biologically active. 20-30% is bound to proteins and 5-15% is complexed, i.e. it forms stable compounds with other substances such as phosphate. As a result, it is less freely available than ionized magnesium.
Magnesium also plays an important role in the activation of vitamin D, which takes place in the liver and kidneys. In the bones, it primarily contributes to mineralization, thereby stabilizing the bone substance and preventing the dreaded osteoporosis.
Magnesium deficiency is dangerous
Despite its essential importance, many people suffer from a latent magnesium deficiency – often without realizing it. An unbalanced diet, chronic stress or certain medications can impair the absorption or availability of magnesium and lead to long-term health problems. Symptoms such as muscle cramps, fatigue, cardiac arrhythmia and even mood swings can indicate a deficiency. Supplementation is therefore advisable in most cases – even without a proven deficiency in the blood analysis. This is because the magnesium concentration in the blood often appears to be sufficient due to the release of magnesium from the dynamic store. It is therefore a fallacy to believe that there is no magnesium deficiency if the magnesium concentration in the blood is sufficient.
Supplementation is usually advisable, as adults need around 300-400 mg of magnesium per day. Depending on gender, age and activity, the requirement can vary upwards. However, if the stores are empty, supplementation can also be increased. Higher doses, spread over several doses, can be useful to replenish empty stores over a period of several weeks or months.
Organic magnesium compounds for supplementation
Magnesium can be supplemented in various compounds:
a) Organic compounds:
Magnesium citrate: Highly bioavailable, ideal for deficiencies and digestive problems.
Magnesium glycinate: Particularly gentle on the stomach, good for stress and sleep problems.
b) Inorganic compounds:
Magnesium oxide: High magnesium concentration, but less absorbable. More suitable for constipation.
Magnesium sulphate: Is often used for short-term applications (e.g. as a laxative).
Magnesium is important for the microbiome
However, magnesium is not only important for humans, but also for the trillions of microorganisms that live in our gut. The link between magnesium and gut health is increasingly becoming the focus of research and shows how closely the mineral balance and the microbiome are connected.
How magnesium influences the microbiome
Magnesium affects the microbiome via various mechanisms.
a) Regulation of the intestinal flora:
Studies show that magnesium supports the maintenance of a diverse and stable intestinal flora. Magnesium can promote the growth of beneficial bacteria such as Bifidobacterium and Lactobacillus, which are important for a healthy intestinal barrier and a balanced immune response.
Low magnesium levels, on the other hand, can promote the growth of pro-inflammatory or pathogenic bacteria such as Enterobacteriaceae, leading to an imbalance (dysbiosis).
A high diversity of the microbiome is important to keep the intestinal flora stable against external influences and to be able to use the full functional diversity of the bacteria.
b) Anti-inflammatory effects
Magnesium influences the immune response in the intestine. It has an anti-inflammatory effect by inhibiting the excessive production of pro-inflammatory cytokines. Proinflammatory cytokines are signaling proteins that are produced by the immune system and promote inflammatory reactions. They play a central role in the immune response by activating cells of the immune system and promoting their migration to sites of inflammation. Although they are necessary to fight infection or repair tissue damage, excessive or chronic inflammatory responses caused by pro-inflammatory cytokines can be harmful to health.
A magnesium deficiency can promote these inflammatory processes and weaken the intestinal barrier – a crucial mechanism in inflammatory bowel diseases such as Crohn’s disease or ulcerative colitis.
In addition, a strong immune system in women is crucial for controlling infections in the vaginal area, such as those caused by Candida albicans or Gardnerella vaginalis, thereby preventing vaginal dysbiosis.
c) Changes in metabolite production
Short-chain fatty acids (SCFAs) such as butyrate, which are produced by beneficial intestinal bacteria, are essential for supplying energy to intestinal cells and maintaining barrier function. Magnesium deficiency can reduce the bacteria that produce these metabolites. The growth of pathogenic bacteria supported by magnesium deficiency can also promote the production of toxic substances.
d) Strengthening the intestinal barrier
The intestinal barrier protects humans from harmful microorganisms and toxins. Magnesium plays an essential role in maintaining this barrier by promoting the production of mucus and tight junction proteins that tightly bind intestinal cells together. A magnesium deficiency can weaken the barrier, making it easier for bacteria and toxins to enter the bloodstream.
This can trigger systemic inflammation associated with chronic conditions such as inflammatory bowel disease, autoimmune disorders and even neurodegenerative diseases.
e) Influence on the microbiome-gut-brain axis
Magnesium has an indirect effect on the so-called microbiome-gut-brain axis. By supporting healthy gut flora, it helps to regulate neurotransmitters such as serotonin and the hormone melatonin, which play an important role in both the gut and the brain. Even though serotonin cannot cross the blood-brain barrier into the brain, the microorganisms form important precursors of serotonin.
In the brain, magnesium is crucial for the production of serotonin, as it acts as a cofactor for the enzyme tryptophan hydroxylase, which converts the amino acid tryptophan into serotonin. It also contributes to the conversion of serotonin into the hormone melatonin.
A magnesium deficiency, on the other hand, can disrupt communication between the gut and brain. Via the microbiota-gut-brain axis, a lack of precursor molecules can lead to disturbances in neurotransmitter production (e.g. serotonin), which is associated with mood problems such as depression and anxiety.
Dysbiosis in the gut can also indirectly promote neuroinflammatory processes in the brain.
Magnesium is essential for a healthy microbiome
An adequate intake of magnesium strengthens the microbiome, promotes diversity and has a positive effect on health.
A magnesium deficiency, on the other hand, can significantly disrupt the microbiome by reducing beneficial bacteria, favoring pro-inflammatory bacteria and weakening the intestinal barrier. This not only has local effects on gut health, but also influences systemic processes such as immune defense and mental health.
The intake of sufficient magnesium is therefore essential to maintain a healthy microbiota and the associated functions. An adequate supply from food is usually not guaranteed, which is why supplementation is usually advisable. An additional intake of around 400 mg per day is usually sufficient if the dynamic stores are replenished. If this is not the case or if there are high magnesium-consuming factors such as sport or stress, higher doses may be necessary. An overdose is rare, as excess magnesium is excreted via the kidneys in healthy people. (JS)
Sources and further reading
Geiger, H., & Wanner, C. (2012).
Magnesium in disease.
Clinical Kidney Journal, 5(Suppl 1), i25–i38. https://doi.org/10.1093/ndtplus/sfr165
Jahnen-Dechent, W., & Ketteler, M. (2012).
Magnesium basics.
Clinical Kidney Journal, 5(Suppl 1), i3–i14. https://doi.org/10.1093/ndtplus/sfr163
Lobionda, S., Sittipo, P., Kwon, H. Y., & Lee, Y. K. (2019).
The role of gut microbiota in intestinal inflammation with respect to diet and extrinsic stressors.
Microorganisms, 7(8), 271. https://doi.org/10.3390/microorganisms7080271
Mazur, A., Maier, J. A. M., Rock, E., Gueux, E., Nowacki, W., & Rayssiguier, Y. (2007).
Magnesium and the inflammatory response: Potential physiopathological implications.
Archives of Biochemistry and Biophysics, 458(1), 48–56. https://doi.org/10.1016/j.abb.2006.03.031
Rosanoff, A., Weaver, C. M., & Rude, R. K. (2012).
Suboptimal magnesium status in the United States: Are the health consequences underestimated?
Nutrition Reviews, 70(3), 153–164. https://doi.org/10.1111/j.1753-4887.2011.00465.x
Winther, G., Jørgensen, B. M. P., Elfving, B., Nielsen, D. S., Kihl, P., Lund, S., Sørensen, D. B., & Wegener, G. (2015).
Dietary magnesium deficiency alters gut microbiota and leads to depressive-like behaviour.
Acta Neuropsychiatrica, 27(3), 144–150. https://doi.org/10.1017/neu.2015.7
Wolf, F. I., & Cittadini, A. (2003).
Chemistry and biochemistry of magnesium.
Molecular Aspects of Medicine, 24(1–3), 3–9. https://doi.org/10.1016/S0098-2997(02)00087-0
