Blood Levels of Vitamin C Predict Stroke

by | Jan 19, 2016 | 2008, Cardiovascular Health, Stroke, Vitamin C

Written by Greg Arnold, DC, CSCS. Those in the highest fourth of vitamin C blood levels had a 42% lower risk of stroke.

Stroke is the third leading cause of death in Americans, with 795,000 strokes estimated to have occurred in 2010, causing about 137,000 deaths and costing our healthcare system $73.7 billion. 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).

Fortunately, nutrition can play a significant role in helping minimize stroke risk. This includes olive oil (2), 1000 mg per day of potassium (3), at least 35 grams of fiber (4), 47 mg of flavonols (5), and 100 milligrams of magnesium (6) per day. Now research (7) suggests that blood levels of vitamin C may be an accurate predictor of stroke risk.

In the study, 20,649 men and women between the ages of 40 and 79, no history of stroke and participating in the European Prospective Investigation into Cancer–Norfolk prospective population study (8) completed a health questionnaire, underwent a physical examination and were followed for an average of 9.5 years.

Over the course of the study, there were 448 strokes among the 20,649 subjects. The researchers found that those with the highest 25% of vitamin C blood levels (at least 66 micromole/Liter) had a 42% lower risk of stroke compared to those with the lowest 25% of vitamin C blood levels (less than 41 micromole/Liter, p = 0.001) independently of age, sex, smoking, body mass index (BMI), systolic blood pressure, cholesterol, physical activity, prevalent diabetes and heart attack, social class, alcohol consumption, and any supplement use.

When looking further, the researchers noted a 17% reduction in stroke risk with every 20 micromoles per Liter increase in vitamin C blood levels. The significance of this finding is that one additional serving of fruits and vegetables per day can increase vitamin C blood levels by 20 micromoles per Liter (9). When it came to recommending a vitamin C dose, the researchers recommended no more than 100 milligrams per day, as doses above 100 mg per day do little to increase vitamin C blood levels (10).

For the researchers, blood levels of vitamin C “may serve as a biological marker of lifestyle or other factors associated with reduced stroke risk and may be useful in identifying those at high risk of stroke.”

Source: Myint, Phyo K., et al. “Plasma vitamin C concentrations predict risk of incident stroke over 10 y in 20 649 participants of the European Prospective Investigation into Cancer–Norfolk prospective population study.” The American journal of clinical nutrition 87.1 (2008): 64-69.

© 2008 American Society for Nutrition

Posted March 27, 2014.

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:

  1. American Heart Association Update. Heart Disease and Stroke Statistics—2007 Update. Circulation. 2007;115:e69- e171
  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. Myint PK. Plasma vitamin C concentrations predict risk of incident stroke over 10 y in 20 649 participants of the European Prospective Investigation into Cancer–Norfolk prospective population study . Am J Clin Nutr 2008 Jan;87(1):64-9
  8. Day N, Oakes S, Luben R, et al. EPIC-Norfolk: study design and characteristics of the cohort. European Prospective Investigation of Cancer. Br J Cancer 1999;80(suppl 1):95–103
  9. Khaw KT, Bingham S, Welch A, et al. Relation between plasma ascorbic acid and mortality in men and women in EPIC-Norfolk prospective study: a prospective population study. European Prospective Investigation into Cancer and Nutrition. Lancet 2001;357:657– 63
  10. Levine M, Rumsey SC, Daruwala R, Park JB, Wang Y. Criteria and recommendations for vitamin C intake. JAMA 1999;281:1415–23