The Benefits of Magnesium for the Body

Magnesium is one of the most abundant minerals in the human body. It acts as a cofactor in over 300 enzymatic reactions, supporting a wide range of processes from bone metabolism to muscle contraction, nervous system function, and energy production.

The Benefits of Magnesium for the Body

What Is Magnesium?

Magnesium comes primarily from dietary sources, is absorbed in the intestine, stored in different tissues—especially the bones—and excreted mainly through the urine.

Where Is Magnesium Found in the Body?

• Bones: 50–60%, helping maintain calcium and phosphorus balance.

• Skeletal muscles: 25%, essential for contraction and relaxation.

• Liver, nervous system, kidneys, and other organs: 15%.

Approximately 98–99% of magnesium is intracellular, with only 1–2% extracellular, highlighting the importance of maintaining magnesium inside cells.
An average adult has around 24 grams of magnesium in the body.

Magnesium is an essential mineral involved in over 300 chemical reactions in the human body. About half of the magnesium in your body is stored in bones and teeth, while the rest supports energy production in cells, nerve signal transmission, and muscle relaxation after contraction.

European Health Authority Guidelines

In 2012, the European Food Safety Authority (EFSA) and the European Commission reviewed health claims for foods and supplements containing magnesium. They concluded that magnesium can legitimately contribute to:

• Normal energy metabolism

• Normal nervous system and muscle function

• Electrolyte balance

• Protein synthesis and normal cell division

• Normal psychological function

• Bone and dental health

• Reduction of fatigue

Important: For these claims to apply, products must contain at least 56 mg of magnesium per 100 g, 100 ml, or per serving.

Claims That Are Not Allowed

Magnesium supplements cannot claim to:

• Maintain normal blood pressure, including during pregnancy

• Reduce stomach acidity

• Improve stress resilience

• Support lipid metabolism

• Support hormonal health

• Act as antioxidants

• Aid blood clotting

• Support the immune system

• Maintain normal blood sugar

• Reduce anxiety

These claims were banned due to insufficient scientific evidence.

Magnesium Deficiency: Symptoms and Risks

Early signs of magnesium deficiency include:

• Loss of appetite

• Nausea and vomiting

• Fatigue

Advanced deficiency may cause:

• Numbness or tingling

• Muscle cramps

• Tremors

• Irregular heartbeat

At-risk groups include:

• Older adults

• People with alcohol use disorders

• Individuals taking diuretics, potassium salts, or hormonal contraceptives

Potential Uses of Magnesium

Beyond correcting deficiencies, magnesium is commonly used (though evidence may vary) for:

• Supporting cardiovascular health, bone health, and preventing kidney stones and type 2 diabetes

• Relieving premenstrual symptoms and migraines

• Improving physical performance

• Reducing muscle cramps and constipation

• Reducing stress and anxiety

Effectiveness of Magnesium

• Laxative effect: High doses of magnesium sulfate or carbonate (over 350 mg in a single intake) can act as a laxative.

• Cardiovascular health: Diets rich in magnesium (~300 mg/day) with adequate calcium and fiber may help protect against hypertension, but supplementation alone has not proven effective for preventing or treating heart disease.

• Diabetes: Magnesium deficiency may worsen insulin resistance in diabetics. Some studies suggest magnesium supplementation could improve insulin sensitivity, though more research is needed.

• Premenstrual symptoms: Magnesium combined with vitamin B6 may reduce uterine muscle tension, easing PMS symptoms.

• Kidney stones: Magnesium increases calcium solubility in urine, potentially preventing calcium-based kidney stones.

• Athletic performance: Exercise can reduce magnesium stores, potentially lowering performance, though research on supplementation is mixed.

• Muscle cramps: Magnesium’s relaxing effect may reduce cramps, but studies are contradictory.

• Osteoporosis, stress, anxiety, migraines: Effectiveness of supplementation is not fully proven.

Precautions

• People with kidney insufficiency should avoid high-dose magnesium supplements.

• Diarrhea is the main side effect, which can be minimized by:

  • Taking less than 350 mg at a time

  • Taking magnesium with meals

  • Choosing less laxative forms (chloride, gluconate, citrate)

• Avoid taking magnesium simultaneously with certain antibiotics (cyclines, quinolones) or osteoporosis medications.

Forms and Dosage

Magnesium supplements are available as:

• Tablets

• Powders

• Liquid solutions

Recommended daily intake:

• Men: 420 mg/day

• Women: 320 mg/day

• Adolescents, pregnant or breastfeeding women: 400 mg/day

Magnesium deficiency often coexists with calcium deficiency, so these minerals are frequently combined in supplements.

Dietary Sources of Magnesium

Magnesium is naturally present in:

• Chocolate

• Legumes

• Whole grains

• Nuts and seeds

• Dark green leafy vegetables

• Brewer’s yeast and wheat germ

• Certain mineral waters (e.g., DonatMg, Hépar, Hydroxydase, Rozana)

Incorporating these foods into your diet is an effective way to maintain healthy magnesium levels.

Magnesium-Rich Foods

A balanced diet can theoretically meet daily magnesium needs, yet most adults consume less than recommended. According to the EFSA NDA group, the adequate intake (AI) is:

• Men: 350 mg/day

• Women: 300 mg/day

• Children: 170–300 mg/day (depending on age)

Foods rich in magnesium include:

• Cocoa and dark chocolate

• Seafood

• Nuts and seeds (almonds, walnuts, hazelnuts)

• Whole grains

• Fatty fish

• Vegetables and dried fruits

Less magnesium is found in lean meats, eggs, and white bread. Refined products, fats, alcohol, phytates (from plant foods), calcium, and phosphates reduce intestinal absorption of magnesium.

Mineral water is also an excellent source, especially when magnesium is in the chloride form, which is naturally highly soluble.

How Magnesium Is Absorbed

The intestine is the main site of absorption, with only 30–50% of dietary magnesium absorbed (about 100 mg daily). The rest is excreted in stools.

Magnesium absorption occurs via two mechanisms:

1. Paracellular transport (passive) – The majority of magnesium is absorbed in the small intestine through tight junctions between epithelial cells.

2. Transcellular transport (facilitated diffusion) – Magnesium moves into intestinal cells and then into the blood through an energy-dependent mechanism.

Absorption is influenced by:

• The chemical form of magnesium

• Dietary balance – Alcohol reduces absorption and increases urinary loss.

• Hormonal factors – Stress hormones like adrenaline and cortisol can increase magnesium loss.

The Role of Magnesium

Magnesium supports many cellular and tissue functions, including:

• Reducing fatigue

• Maintaining electrolyte balance

• Supporting energy metabolism

• Regulating nerve and muscle function

• Maintaining healthy bones and teeth

Magnesium and Fatigue

Fatigue is a state of weakness unrelated to activity and persists after rest. Magnesium deficiency can cause fatigue because the body’s systems cannot function optimally. Ensuring a magnesium-rich diet or supplementing when needed can help restore energy levels.

Magnesium and Stress

Stress—whether physical (pain, temperature, noise) or psychological (emotions, tension, workload)—triggers neurotransmitters that rely on calcium as a messenger. Excess calcium in cells leads to magnesium loss, creating a vicious cycle of stress. Adequate magnesium intake helps modulate calcium and mitigate stress effects.

Everyday stressors, like work difficulties, illness, personal challenges, new tasks, or exams, consume magnesium, making dietary or supplemental support important.

Magnesium and Muscle Function

Magnesium acts as a calcium antagonist, regulating muscle contraction. It prevents excess calcium accumulation and hyper-contractility. At rest, magnesium levels in muscle cells are 10,000 times higher than calcium, highlighting its critical role.

Signs of Magnesium Deficiency

A blood magnesium test is commonly used to detect deficiencies or monitor supplementation. Causes of deficiency include:

• Insufficient dietary intake

• Increased physiological needs, such as growth in children or pregnancy

• Reduced intestinal absorption or increased gastrointestinal/renal losses

Common signs of low magnesium include:

• Fatigue

• Stress

• Muscle cramps

• Eyelid twitching

Choosing the Right Magnesium Source: Marine Magnesium

Supplementation can be beneficial when magnesium balance is disrupted. Marine magnesium is derived from seawater.

• Marine magnesium oxide is obtained through thermal decomposition of magnesium, a technique developed in the 1950s by Joseph Aman.

• It has 99.5% purity, contains no allergens or GMOs, and is suitable for medications and dietary supplements.

Marine magnesium provides a high-quality, bioavailable source, making it ideal for restoring magnesium levels safely and effectively.

Conclusion

Related articles

• 6 key benefits of magnesium you should know
• 10 essential health benefits of magnesium.
• The basics of anti aging diet eating.
• What is magnesium for essential roles.
• The benefits of magnesium why you need it.

📚 Medical sources

• National Institutes of Health (NIH) – Magnesium Factsheet
• Mayo Clinic – Magnesium: Uses and Deficiency
• Cleveland Clinic – Magnesium and Health
• Harvard Health – Magnesium: The Important Mineral