Dietary magnesium deficiency induces heart rhythm changes, impairs glucose tolerance, and decreases serum cholesterol in post menopausal women.
Level 3 - non-randomized controlled study
Non-randomized, single-arm controlled metabolic ward depletion-repletion trial.
PubMed 17536123 · doi:10.1080/07315724.2007.10719593
What was done
Thirteen postmenopausal women (aged 47 to 75 years; 14 originally recruited) completed a 136-day metabolic unit study. Participants consumed a basal Western-type diet providing 4.16 mmol (101 mg) magnesium per 2000 kcal (~33% of the RDA) for up to 78 days. Repletion followed for 58 days with 200 mg/day magnesium supplementation as magnesium gluconate. If adverse heart rhythm changes developed, subjects entered repletion early. Electrolyte balance, red blood cell membrane magnesium, heart rhythm, serum glucose, serum cholesterol, urinary electrolytes, and erythrocyte superoxide dismutase were assessed.
What was found
Heart rhythm changes appeared in 5 women during depletion, causing 4 to enter repletion early between days 42 and 64. Three women developed atrial fibrillation and flutter that responded quickly to magnesium supplementation. Magnesium deprivation led to non-positive magnesium balance, which became highly positive upon repletion. Depletion decreased red blood cell membrane magnesium, serum total cholesterol, and erythrocyte superoxide dismutase concentrations, while increasing urinary sodium and potassium excretion and increasing serum glucose concentration. Exact numerical values were not reported in the abstract.
Why it matters
This study demonstrates under controlled metabolic ward conditions that severe dietary magnesium restriction can induce clinically relevant cardiac arrhythmias and impair glycemic regulation in postmenopausal women.
Limits
The sample size was very small with only 13 completers, and there was no parallel control group. The study examined only postmenopausal women, limiting generalizability to other demographics. Specific numerical data and statistical measures were not provided in the abstract.
Cited by
- context Heart arrhythmia is one of the earliest symptoms of magnesium deficiency.