Magnesium is a macromineral found in nuts and seeds, dark green leafy vegetables, tofu, legumes and grains. It is second to potassium in terms of concentration in the body’s cells. Magnesium is thought to work well with calcium and they often recommended together. The Recommended Daily Amount (RDA) for magnesium in the UK is 400 mg for males and 310 mg for females.
The primary function of magnesium is its role in energy production. It is involved in over 300 enzymatic processes in the body. Magnesium also assists in the uptake of potassium and calcium. Low levels of magnesium have been associated with various diseases including heart disease, high blood pressure, kidney stones, cancer, insomnia, PMS and menstrual cramps.
Magnesium deficiency due to low dietary intake in otherwise-healthy people is uncommon because the kidneys limit urinary excretion of this mineral however excess loss of this mineral due to certain health conditions, medications and alcoholism can lead to deficiency. Signs and symptoms of magnesium deficiency include fatigue, mental confusion, irritability, weakness, heart disturbances, depression, loss of appetite and insomnia.
Diabetes– It has been reported that magnesium deficiency may also be implicated in diabetes mellitus which in turn may contribute to metabolic complications of diabetes including vascular disease and osteoporosis (1). Data gathered from studies evaluating insulin responsiveness showed it was dependent on magnesium levels which demonstrates the importance of magnesium as a determinant of insulin action (2).
Allergies– Magnesium deficiency has been implicated in various types of allergies and allergic skin reactions in many studies. A study in the 1980’s found that mice deprived of magnesium, compared to a control group, developed allergy like symptoms including skin redness and increased scratching. An increase in white blood cells and histamine levels in an allergy-like crisis was also noted (3).
Fibromyalgia– Magnesium is known to regulate or inhibit many nerve receptors which are implicated in certain types of fibromyalgia pain. Studies have shown that magnesium supplementation may have an effect on neuropathic pain by blocking these receptors (4) (5).
Anxiety– Research also supports the correlation with low magnesium intake and psychiatric disorders.
A 2009 study published in the Australian and New Zealand Journal of Psychiatry reported an inverse relationship between magnesium intake and depression and anxiety disorders (6). In a 2012 study published in the journal Neuropharmacology, researchers conducting tests on mice found that low magnesium levels in the mice caused them to enter states of hyper-excitability and enhanced anxiety (7).
Asthma– A number of studies have demonstrated the importance of magnesium for those suffering with asthma. A 2010 study involving fifty-two participants; half of whom received magnesium supplementation and the other half placebo. The outcome of the study revealed those taking magnesium supplementation showed a significant improvement in lung activity compared to the placebo group (8). Furthermore, a study in 1994 noted that people who have diets lower in magnesium have more asthmatic symptoms and self-reported wheezing (9).
ADHD– Magnesium is often used in the treatment and prevention of attention deficit disorder (ADD) and attention deficit hyperactivity disorder (ADHD). There is evidence to support the idea that magnesium deficiency is a significant factor in the development of these conditions. In a 1997 study ninety-five percent of the children examined with ADD or ADHD were magnesium deficient (10).
Fatigue and tiredness—Magnesium contributes to normal energy-yielding metabolism. This suggests that a deficiency may be a factor in cases of tiredness and fatigue, and so a supplement may help prevent this. This may also be of value to those participating in sports who wish to ensure the correct functioning of their energy metabolism to maximise performance. Magnesium also directly contributes to a reduction in tiredness and fatigue. People suffering from chronic fatigue syndrome are often found to have low levels of magnesium.
Osteoporosis and Bone Health– Magnesium is needed for the maintenance of normal bones. This suggests that if deficient, bone structure may be affected and so supplementing with calcium may help to prevent such bone- related ailments. This would also make it a useful supplement in the support of healing following fractures and broken bones.
Magnesium is very well tolerated however in high doses certain forms of magnesium supplementation can cause loose stools, possibly accompanied with abdominal cramping and nausea. The forms of magnesium most commonly reported to cause diarrhoea include magnesium carbonate, chloride, gluconate, and oxide. The Tolerable Upper Safe Level for supplemental magnesium is 350mg for both males and females.
