Written by Greg Arnold, DC, CSCS. In two studies with over 180,000 female registered nurses, those with the highest magnesium had a 19% reduced risk of stroke, compared to the lowest users. Those with the highest magnesium and potassium intake had a 28% reduced risk of stroke.
Stroke is the third leading cause of death in Americans, with 795,000 strokes expected to occur in 2010 (about one stroke occurring every 40 seconds), causing about 137,000 deaths (about one death every four minutes). Stroke is expected to cost our healthcare system $73.7 billion in 2010. While 55,000 more women than men have a stroke each year, African Americans have almost twice the risk of first-ever stroke compared with whites (1, 2).
Now a new research review (3) suggests that magnesium and potassium intake may influence stroke risk. In the study, researchers analyzed data on stroke incidence in two large cohort studies: the Nurse’s Health Study 1 (86,149 female registered nurses) and the Nurse’s Health Study 2 (94,715 female registered nurses) (4). In each study, follow-up questionnaires were sent to each subject every two years, providing information on specified portions of 131 foods and use of vitamin and mineral supplements used in previous research (5). The average follow-up time was 30 years for those in the Nurse’s Health Study 1 and 22 years for those in the Nurse’s Health Study 2.
The researchers found that those with the highest 20% of magnesium intake (868 milligrams per day) had a 19% reduced risk of stroke compared to those with the lowest 20% of intake (662 mg per day, p = 0.01). For the highest 20% levels of potassium intake (883 milligrams per day), there was an 11% reduced risk compared to the lowest 20% of potassium intake (647 mg/day, p = 0.01).
When researchers combined magnesium and potassium intake into a “mineral diet core” (6), stroke risk reduction was even greater when both magnesium and potassium intake was high. Specifically, those with the highest 20% mineral diet score had a 28% reduced risk of all types of stroke (p < 0.001) and a 22% reduced risk of a type of stroke called ‘ischemic stroke’ (p = 0.01).
For the researchers, “A combined mineral diet score was inversely associated with risk of stroke”, that “high intakes of magnesium and potassium but not calcium were also significantly associated with reduced risk of stroke in women” but that “the effect of these minerals on risk of stroke independent of food sources is difficult to define.”
Source: Adebamowo, Sally N., Donna Spiegelman, Walter C. Willett, and Kathryn M. Rexrode. “Association between intakes of magnesium, potassium, and calcium and risk of stroke: 2 cohorts of US women and updated meta-analyses.” The American journal of clinical nutrition (2015): ajcn100354.
© 2015 American Society for Nutrition
Posted May 26, 2015.
Greg Arnold is a Chiropractic Physician practicing in Hauppauge, NY. You can contact Dr. Arnold directly by emailing him at PitchingDoc@msn.com or visiting his web site at www.PitchingDoc.com.
References:
- American Heart Association Update. Heart Disease and Stroke Statistics—2007 Update. Circulation. 2007;115:e69- e171
- “Impact of Stroke” from the American Heart Association Website
- Adebamowo SN. Association between intakes of magnesium, potassium, and calcium and risk of stroke: 2 cohorts of US women and updated meta-analyses. Am J Clin Nutr 2015 May 6. pii: ajcn100354. [Epub ahead of print]
- Whelton PK, Klag MJ. Magnesium and blood pressure: review of the epidemiologic and clinical trial experience. Am J Cardiol 1989;63:26G–30G
- Ascherio A, Hennekens C, Willett WC, Sacks F, Rosner B, Manson J, Witteman J, Stampfer MJ. Prospective study of nutritional factors, blood pressure, and hypertension among US women. Hypertension 1996;27:1065–72
- Hu FB, Stampfer MJ, Rimm E, Ascherio A, Rosner BA, Spiegelman D, Willett WC. Dietary fat and coronary heart disease: a comparison of approaches for adjusting for total energy intake and modeling repeated dietary measurements. Am J Epidemiol 1999;149:531–40.
