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Magnesium (Mg)

vitguidemagnesiumMagnesium is an essential mineral. An adult contains around 20-30 grams of magnesium. Approximately half of the body's magnesium supply is stored in the bones. The rest is distributed in the muscles, liver, nerve tissue and other soft tissues. Magnesium is mainly found inside the cells where it supports over 300 different enzymatic processes.

Functions and importance for

  • Strong bones. Together with calcium and phosphor, magnesium constitutes the solid matter of bone tissue
  • Energy turnover and energy levels
  • Nervous system and nerve impulse transmission
  • Blood pressure and heart
  • Muscle function and muscle contraction
  • Maintenance of the electrolyte balance (fluid and sodium balance) with sodium and potassium
  • Protein synthesis, including muscles, hormones, and skin
  • Cell division
  • Alkalizing agent that prevents acid overload

Deficiencies and poor utilisation may be caused by

  • Unbalanced diets and prolonged dieting
  • Lack of vitamin B6 causes poor cellular uptake of magnesium
  • Too much calcium, phosphor, and sodium (salt)
  • Oxalic acid (found in acidic leaves, tea, spinach, cocoa, and rhubarb)
  • Large consumption of alcohol and other stimulants
  • Chronic diarrhea
  • Diuretics
  • Stress

Deficiency symptoms

Often very similar to those that occur with calcium deficiencies:

  • Neural and mental disturbances
  • Trembling and inner unrest
  • Muscle fatigue
  • Muscle cramps
  • Fatigue
  • Reduced appetite
  • Reduced appetite
  • Nausea
  • Constipation and irritable colon
  • Elevated blood pressure
  • Insidious decalcification of the skeleton


Mainly kernels, almonds, nuts, seeds, beans, oats, whole-grain, avocado, cabbage and other vegetables, dark chocolate, and seaweed. Also, dairy products, fruit, berries, meat, fish, and sea salt.

Magnesium content in mg per 100 grams

Pumpkin seeds 540
Cocoa powder 523
Almonds 265
Oats 117
Avocado, parsley 29

Recommended daily allowance

Adults: 11 years of age and older: 375 mg
Pregnancy: Slightly more (with help from supplements)
Children: 1-10 years of age: 85 mg

Increased need

  • Unbalanced diets
  • Above mentioned deficiency symptoms
  • Pregnancy
  • Diuretics

Magnesium, supplements, and medical drugs

Magnesium is used in nutritional supplements as well as in certain medical drugs. The most bio-available magnesium sources are magnesium carbonate, magnesium acetate, magnesium orotate, and magnesium amino acid chelate. Magnesium oxide (E530) is a tablet excipient that is also used against heart burn and constipation. This magnesium compound is difficult for the body to absorb and does therefore not affect the body's magnesium status.

Some supplements contain several magnesium sources in order to ensure the optimal bio-availability and utilisation of magnesium.

Over dosing - side effects

Rarely seen at doses below 2,000 mg and with normal kidney function. If a person consumes more magnesium than the body can absorb - especially in the form of laxatives with magnesium - it may result in:

  • Diarrhea

In people with impaired kidney function, too much magnesium may in extreme cases cause:

  • Slow heart rate and low blood pressure
  • Weak muscles and possibly paralyses

Important information

There is an interaction between magnesium and calcium. For that reason, these two minerals must be ingested in the right balance. Normally, magnesium and calcium should be consumed in a 1:2 ratio. In the case of kidney diseases and serious heart complications it is advised only to take magnesium supplements if directed by a physician