How Magnesium Affects Health and Which Foods Contain It

Magnesium is a very important mineral for the functioning and health of our body. Learn which foods are rich in magnesium and how it affects our body. Which magnesium-rich dietary supplements should you take? Read more!

Magnesium is required for the activity of about 300 different enzymes in our body.
The body of an adult contains about 24 g of magnesium, of which 60% is found in the bones and the rest in soft tissues. Less than 1% is found in the serum.

Here are several reasons why magnesium is important for our health:

• Participates in energy production (ATP) by breaking down and utilizing carbohydrates, proteins, and fats as a metabolic mediator (glycolysis, phosphorylation).

• Acts as a calcium antagonist (controls calcium entry into the cell membrane) and enables muscle contraction.

• Contributes to the protection of heart muscle function, regulates potassium movement in myocardial cells, protects against stress, has a vasodilatory effect on cardiac and peripheral arteries, and reduces plaque formation.

• Plays a role in the structure of bones and teeth, mitochondria, proteins, and nucleic acids.

• Deficiency leads to hypocalcemia because it affects parathyroid hormone and 1,25(OH)₂ vitamin D, the two main regulators of calcium homeostasis.

• Various (in vivo) studies have shown that regular magnesium intake has a preventive effect on the development of diabetes.

• Participates in nerve impulse transmission and the production of serotonin (the so-called happiness hormone) in the brain. It also protects brain cells from damage, which is important for the prevention of Parkinson’s and Alzheimer’s disease.

• Has an important role in detoxification. It is essential for the production of glutathione, an antioxidant responsible for removing heavy metals (mercury, lead, arsenic) from the body.

Magnesium Deficiency and Excess

It is known that magnesium deficiency causes weakness, fatigue, muscle cramps, dizziness, headache, and constipation. Deficiency also affects the nervous system, causing anxiety, irritability, lethargy, memory difficulties, and insomnia. Many studies indicate a link between low magnesium levels and depression.

Symptoms of chronic magnesium deficiency include reduced immunity, persistent fatigue, decreased bone density (leading to osteoporosis), anemia, and arrhythmia.

Although magnesium deficiency is difficult to define, there are special conditions that require increased intake:

• Alcoholism

• Use of certain medications (tetracyclines, quinolone antibiotics, loop and thiazide diuretics, proton pump inhibitors)

• Gastrointestinal diseases

• Type 2 diabetes

• Older population

• Pregnancy

• Children in growth and development

• Everyday stress

Excess magnesium in the body, or hypermagnesemia, is very rare because excess magnesium is excreted by the kidneys in healthy individuals. Problems occur with reduced kidney function. Other possible causes include excessive magnesium intake, Addison’s disease, lithium therapy, reduced thyroid hormone secretion, and milk-alkali syndrome.

Caution is also advised with long-term use of laxatives and antacids, as they often contain magnesium salts.

Symptoms of excess magnesium range from mild (confusion, drowsiness, muscle weakness, ataxia) to severe (vasodilation and sudden drop in blood pressure leading to reduced consciousness, bradycardia, cardiac arrhythmias, hypoventilation), and can even result in cardiac arrest.

Foods Rich in Magnesium

It is important to note that today’s agricultural soil is increasingly poor in magnesium. Artificial fertilization depletes magnesium content because fertilizers usually contain nitrogen, phosphorus, and potassium, but not magnesium. As a result, we consume too little of this mineral.

Thermal processing causes foods to lose 40–70% of magnesium. Certain compounds can hinder magnesium absorption: phytates, fiber, fats, oxalic acid, potassium, iron, phosphorus, calcium, manganese, and alcohol. Vitamin D, lactose, and vitamin B6 increase magnesium absorption; vitamin B6 is important for transporting magnesium into cells.

The current recommendation for adults is 300–400 mg of magnesium per day. A typical diet provides 180–300 mg per day, of which only about one third is absorbed.

Seawater contains large amounts of magnesium, with the highest concentration found in the Dead Sea.

Magnesium is obtained through a balanced diet that includes green leafy vegetables, whole grains, legumes, seeds, nuts, and fruit. Some of the richest sources are pumpkin seeds, wheat germ, almonds, hazelnuts, cocoa, oats, flaxseed, sunflower and chia seeds, Brazil nuts, sesame, peanuts, walnuts, brown rice, soy, buckwheat, spinach, tomatoes, broccoli, dates, raisins, prunes, avocado, banana, potatoes, and fish such as sole and tuna.

Magnesium in Pregnancy

Certain studies have shown that during pregnancy magnesium levels decrease significantly, by up to 30%. This occurs because magnesium is important for preventing miscarriage and preterm birth, reducing leg muscle cramps (common in later stages of pregnancy), and for the synthesis of nucleic acids and proteins needed to build new fetal tissues.

During pregnancy, intestinal transit slows, often causing constipation. Magnesium is important here because it has a mild laxative effect.

In women of reproductive age, magnesium requirements are about 310 mg, while during pregnancy they increase to 350 mg.

The EFSA Panel on Dietetic Products, Nutrition and Allergies (NDA) issued an opinion on adequate magnesium intake for children, adults, pregnant women, and breastfeeding women based on average intake assessed through dietary surveys in nine EU countries (Table 1).

Table 1. Adequate magnesium intake (mg/day)