Magnesium May Benefit Stroke Risk

by | Jan 24, 2012 | 2011, Cardiovascular Health, Magnesium, Stroke

Written by Greg Arnold, DC, CSCS. The results of seven studies involving 241,378 patients, of whom 6,477 had suffered a stroke, revealed that every 100 mg of daily magnesium intake produced a modest but significant 8% reduction in stroke risk.

In the United States, a stroke occurs every 40 seconds, totaling 795,000 Americans each year. Of those Americans suffering a stroke, 137,000 will die, about 1 every 4 minutes, accounting for 1 of every 18 deaths. Stroke is currently the number 4 cause of death in the U.S. and will cost $73.7 billion for stroke-related medical costs and disability in 2010 (1).

While nutrition, including olive oil (2), 1000 mg per day of potassium (3), over 35 grams of fiber per day (4) and over 47 mg of flavonols per day (5) may help with stroke risk, a new study (6) suggests that magnesium may also help.

In the study, researchers reviewed previous research and identified seven studies involving 241, 378 patients, among whom 6,477 patients suffered a stroke. The researchers then identified “a modest but statistically significant” association between increased magnesium intake and stroke risk. Specifically, every 100 mg intake of magnesium per day produced an 8% reduction in stroke risk. When looking at specific types of stroke, the biggest reduction was in ischemic stroke (9% reduced risk) with a smaller risk reduction in intracerebal hemorrhagic stroke (4% reduced risk) but no risk reduction with subarachnoid hemorrhage.

The researchers cite green leafy vegetables, nuts, beans, and whole grains as food sources rich in magnesium, with 157 mg in 1 cup cooked spinach, 77 mg in 1 ounce roasted cashew nuts, 134 mg in 1 cup canned white beans, 88 mg in 1 cup cooked oat bran, and 84 mg in 1 cup cooked brown rice (7). The US Recommended Dietary Allowance of magnesium for women and men 31–70 years of age is 320 and 420 mg per day, respectively (8).

For the researchers, “Dietary magnesium intake is inversely associated with risk of stroke, specifically ischemic stroke.”

Source: Larsson, Susanna C., Nicola Orsini, and Alicja Wolk. “Dietary magnesium intake and risk of stroke: a meta-analysis of prospective studies.” The American journal of clinical nutrition 95.2 (2012): 362-366.

© 2012 American Society for Nutrition

Posted January 24, 2012.

References:

  1. “Impact of Stroke” – posted on the Stroke Association website.
  2.  Salmieri C.  Olive oil consumption, plasma oleic acid, and stroke incidence : The Three-City Study. Neurology 2011. Prepublished online June 15, 2011; DOI 10.1212/WNL.0b013e318220abeb.
  3. Larsson SC. Dietary Potassium Intake and Risk of Stroke A Dose–Response Meta-Analysis of Prospective Studies Stroke. 2011;42:00-00.
  4. Larsson SC. Dietary fiber and fiber-rich food intake in relation to risk of stroke in male smokers. Eur J Clin Nutr advance online publication, March 25, 2009; doi:10.1038/ejcn.2009.16.
  5.  Mink PJ, Scrafford CG, Barraj LM, Harnack L, Hong CP, Nettleton JA, Jacobs DR Jr. Flavonoid intake and cardiovascular disease mortality: a prospective study in postmenopausal women. Am J Clin Nutr. 2007;85:895–909.
  6. Larsson SC.  Dietary magnesium intake and risk of stroke: a meta-analysisof prospective studies. Am J Clin Nutr. 2011 Dec 28. [Epub ahead of print].
  7. U.S. Department of Agriculture, Agricultural Research Service. USDA national nutrient database for standard reference.
  8. Dietary Reference Intakes for calcium, phosphorus, magnesium, vitamin D, and fluoride. Washington, DC: National Academy of Sciences. Institute of Medicine. Food and Nutrition Board, 1997.