Linus Pauling emphasized in our discussions years ago that Vitamin C excreted in the urine did not mean you had too much Vitamin C. He argued that maintaining high plasma vitamin C had all sorts of positive effects. Reduction in the risk of stroke is one of them. A couple of glasses of fresh orange juice a day contains enough vitamin C to cut stroke risk in half. Pauling felt that significantly more vitamin C in the bloodstream had far reaching systemic effects.
Plasma Vitamin C Modifies the Association Between Hypertension and Risk of Stroke
S. Kurl, MD; T.P. Tuomainen, MD; J.A. Laukkanen, MD; K. Nyyssönen, PhD; T. Lakka, MD, PhD; J. Sivenius, MD, PhD; J.T. Salonen, MD, PhD, MscPH
Stroke. 2002;33:1568.
Background and Purpose— There are no prospective studies to determine whether plasma vitamin C modifies the risk of stroke among hypertensive and overweight individuals. We sought to examine whether plasma vitamin C modifies the association between overweight and hypertension and the risk of stroke in middle-aged men from eastern Finland.
Methods— We conducted a 10.4-year prospective population-based cohort study of 2419 randomly selected middle-aged men (42 to 60 years) with no history of stroke at baseline examination. A total of 120 men developed a stroke, of which 96 were ischemic and 24 hemorrhagic strokes.
Results— Men with the lowest levels of plasma vitamin C (<28.4 µmol/L, lowest quarter) had a 2.4-fold (95% CI, 1.4 to 4.3; P=0.002) risk of any stroke compared with men with highest levels of plasma vitamin C (>64.96 µmol/L, highest quarter) after adjustment for age and examination months. An additional adjustment for body mass index, systolic blood pressure, smoking, alcohol consumption, serum total cholesterol, diabetes, and exercise-induced myocardial ischemia attenuated the association marginally (relative risk, 2.1; 95% CI, 1.2 to 3.8; P=0.01). Adjustment for prevalent coronary heart disease and atrial fibrillation did not attenuate the association any further. Furthermore, hypertensive men with the lowest vitamin C levels (<28.4 µmol/L) had a 2.6-fold risk (95% CI, 1.52 to 4.48; P<0.001), and overweight men (25 kg/m2) with low plasma vitamin C had a 2.7-fold risk (95% CI, 1.48 to 4.90; P=0.001) for any stroke after adjustment for age, examination months, and other risk factors.Conclusions— Low plasma vitamin C was associated with increased risk of stroke, especially among hypertensive and overweight men.