We all know that magnesium is an important ingredient that so many of the body’s regulatory and biochemical systems that the impact of low levels spans all areas of health and medical practice. Therefore the symptoms of a magnesium deficiency fall into two broad categories – the physical symptoms of overt deficiency and the spectrum of disease states linked to low magnesium levels.

Symptoms include both:
Classic “Clinical” Symptoms. These physical signs of magnesium deficiency are clearly related to both its physiological role and its significant impact on the healthy balance of minerals such as calcium and potassium. Tics, muscle spasms and cramps, seizures, anxiety, and irregular heart rhythms are among the classic signs and symptoms of low magnesium. (A complete list of the symptoms of magnesium deficiency follows.)

“Sub-clinical” or “latent” Symptoms. These symptoms are present but concealed by an inability to distinguish their signs from other disease states. Caused by low magnesium intake prevalent in nearly all industrialized nations, they can include migraine headaches, insomnia, depression, and chronic fatigue, among others.

The body actually strips magnesium and calcium from the bones during periods of “functioning” low magnesium. This effect can cause a doubly difficult scenario: seemingly adequate magnesium levels that masks a true deficiency coupled by ongoing damage to bone structures. Thus experts advise the suspicion of magnesium deficiency whenever risk factors for related conditions are present, rather than relying upon tests or overt symptoms alone.

The classic physical signs of low magnesium are:


  • Irregular or rapid heartbeat
  • coronary spasms


  • behavioral disturbances
  • Irritability and anxiety
  • lethargy
  • Impaired memory and cognitive function
  • Anorexia or loss of appetite
  • Nausea and vomiting
  • seizures


  • Increased intracellular calcium
  • Hyperglycemia
  • calcium deficiency
  • potassium deficiency


  • weakness
  • Muscle spasms (tetany)
  • tics
  • Muscle cramps
  • hyperactive reflexes
  • Impaired muscle coordination (ataxia)
  • Tremors
  • Involuntary eye movements and vertigo
  • difficulty swallowing

Among children:

  • Growth retardation or “failure to thrive”


-Performing magnesium testing whenever conditions or symptoms associated with magnesium deficiency are present.
-Increasing the threshold at which low blood magnesium is considered problematic, to successfully capture those with marginal deficiencies (from the commonly used 0.7 mmol / l Mg to 0.9 mmol / l Mg.)
-Beginning magnesium therapy and magnesium supplements as soon as possible, for a minimum of one month’s duration or until levels are clearly improved.
-These recommendations echo the general sentiment that magnesium supplementation is safe and recommended, especially for the estimated 75% of the population with below the recommended daily intake of magnesium.

Risk factors created by long-standing chronic low magnesium could be addressed in more people before severe symptoms and chronic disease develop.