Table 5.

Etiology of magnesium deficiency [6].

(i) Reduced dietary intake (processed foods)

(ii) Reduced gastrointestinal absorption (vitamin D deficiency)

(iii) Loss of magnesium from the gastrointestinal tract

Diarrhea and vomiting (acute)

(a) Chronic diarrhea and fat malabsorption:

(1) Celiac disease (all patients with this are deficient) [16]

(2) Regional enteritis

(3) Crohn's disease may require as much as 700 mg/day of magnesium [17]

(4) Resection or small intestine bypass

(5) Laxative use

(iv) Increased renal loss (on average 30% of dietary intake is lost in urine) [18]

(a) Diabetes mellitus/insulin resistance

(1) Due to renal excretion as a result of higher glucose concentrations in the kidney resulting in increased urine output

(b) Alcoholism

(1) Due to decreased intake, gastrointestinal problems, vomiting, phosphate depletion, renal dysfunction, vitamin D deficiency

[19]

(c) Medication induced (see Table 8)

(v) Excessive sweating

(a) On average 10–15% of total output of magnesium may be recovered in sweat

(vi) Increased requirements (pregnancy and growth)

(vii) Older adults: due to lower magnesium intake, decreased absorption, increased renal excretion