Both studies found that vitamin C supplements, and only supplements, are protective of cardiovascular disease, especially major cardiovascular events (such as heart attack or stroke.).
Ideally, these studies should be the basis for recommending vitamin C supplements to the population. Both studies found that "dietary" (what is available from foods) antioxidants have little effect on the risks of heart disease, but that supplemental vitamin C affords considerable protection.
Antioxidant vitamins and coronary heart disease risk: a pooled analysis
http://www.ncbi.nlm.nih.gov/entrez/quer ... s=15585762
RESULTS: Dietary intake of antioxidant vitamins was only weakly related to a reduced CHD risk after adjustment for potential nondietary and dietary confounding factors. Compared with subjects in the lowest dietary intake quintiles for vitamins E and C, those in the highest intake quintiles had relative risks of CHD incidence of 0.84 (95% CI: 0.71, 1.00; P=0.17) and 1.23 (1.04, 1.45; P=0.07), respectively, and the relative risks for subjects in the highest intake quintiles for the various carotenoids varied from 0.90 to 0.99.
Subjects with higher supplemental vitamin C intake had a lower CHD incidence.
Compared with subjects who did not take supplemental vitamin C, those who took >700 mg supplemental vitamin C/d had a relative risk of CHD incidence of 0.75 (0.60, 0.93; P for trend <0.001). Supplemental vitamin E intake was not significantly related to reduced CHD risk.
CONCLUSIONS: The results suggest a reduced incidence of major CHD events at high supplemental vitamin C intakes. The risk reductions at high vitamin E or carotenoid intakes appear small.
Health author Bill Sardi's take on this meta analysis:
Bill Sardio wrote:"This pooled study shows health benefits at >700 mg vitamin C from supplements compared to no supplementation. This ABSOLUTELY disproves the RDA and the false idea that there is a 200 mg daily limit on health benefits!!!!!!!!!!!!!!""
Harvard Nurses Study
Drs. Hickey and Roberts remind us that large, multi-year studies are not very good science for the simple reason they are hard to repeat (and thus verify). However, this 15-year study of 85,000 nurses from Harvard should be convincing for those who prefer large trials.
Vitamin C and risk of coronary heart disease in women
http://www.ncbi.nlm.nih.gov/entrez/quer ... query_hl=7
As summarized here
15-YEAR HARVARD STUDY OF 85,000 FINDS SINGLE VITAMIN C PILL REDUCES HEART DISEASE ALMOST 30%.
abstract wrote:After adjustment for age, smoking, and a variety of other coronary risk factors, we observed a ?modest? significant inverse association between total intake of vitamin C and risk of CHD (relative risk [RR] = 0.73; 95% confidence interval [CI] 0.57 to 0.94).
Among women who did not use vitamin C supplements or multivitamins, the association between intake of vitamin C from diet alone and incidence of CHD was weak and not significant (RR = 0.86; 95% CI 0.59 to 1.26).
In multivariate models adjusting for age, smoking, and a variety of other coronary risk factors, vitamin C supplement use was associated with a significantly lower risk of CHD (RR = 0.72; 95% CI 0.61 to 0.86).
CONCLUSIONS: Users of vitamin C supplements appear to be at lower risk for CHD.
Interestingly, again, dietary intake of vitamin C seemed to have little effect on coronary heart disease risk.
However, if women used vitamin C supplements, their risk was reduced by 27 percent.
Accordingly, it bears repeating, a single 360 mg vitamin C pill daily would save more than 300,000 lives per year.
How did conventional medicine respond? (This was a large study and presumably cost something to produce.)
Did our medical or government authorities recommend to the public that we begin taking completely nontoxic vitamin C pills? Pills that the Harvard study predicts would relieve the suffering of hundreds of thousands and save billions in health care costs?
No, the general response was, as reported by the media:
"It is too early to recommend vitamin C pills. We need more [15 year, 85,000 subject] studies before we can tell people to take vitamin C pills."!?