There have been some controversies regarding C and thickening of the artery walls. Some doctors have stated this could be bad. However, the information carefully omitted whether the inner diameter of the artery has decreased or increased; and far more important, what effect that had on circulation!
Of course, C can cause thickening of the artery walls. Vitamin C is used to produce collagen. Bleeding during scurvy and hemorrhagic fevers is caused by the breakdown of collagen in blood vessels. Since a portion of the heart attacks and other related cardiovascular deaths is due to arterial rupture, and since artery walls can become thinner over one's life if one is low on vitamin C (which most people are), some thickening of artery walls should be expected. This can be quite beneficial, restoring elasticity and tone to the blood vessels. The key to determining this would be the use of a pethsymograph to assess the elasticity of the arteries. (This was not done.) Hard arteries will not stretch, causing high blood pressure waves. Elastic blood vessels will constrict between pulses, and dilate with the pressure wave, lengthening the pulse and helping move blood through the body. Blood vessels are made in part of smooth muscle tissue that is supposed to be elastic. Elastic vessels will seem narrower between pulses. Blood vessels have to be elastic to avoid damage. Good blood vessel diameter is regulated by the serotonin / dopamine balance in the blood, constricting when adrenalin is released, and in response to cold. The simple act of taking blood vessel wall thickness in a cold room vs a hot room will produce considerable changes in thickness and flow rate. If this is not kept constant between the tests, the tests are just plain worthless.
The medical establishment has long sought to pharmacologize all nutritive substances via the AMA and FDA. It has taken acts of congress to prevent them from regulating doses of vitamins and other naturally occurring food substances. Several national science organizations have blasted the FDA repeatedly over their excessively low MDR's or C and other vitamins. The FDA has even tried to prevent our publishing any information on vitamins without prior approval in stark violation of our constitutional rights. (That caused the largest flurry of mail to congress than ever before in the early 90's, larger even than the national health rationing plan.) This is a never ending struggle. L-Tryptophan, a very potent and SAFE anti-depressant was banned for a while, being replaced by the expensive drug Prozac. Effective as that may be, vitamin C presents a far greater threat, as people who get enough vitamin C and other micro-nutrients tend not to get sick. What does medicine study? Healthy people? No, illness. Cure, not prevention. The vast monies spent on cancer research are not for cause and prevention, but for pharmacological cures that can be sold at high profit by the drug companies.
Food is the best medicine. Prevention is the cheapest medicine. But when we cured Tuberculosis, more doctors jumped out of windows than stockbrokers during the Great Depression. The profession has not forgotten.
See http://www.paulingtherapy.com Heart Attack Prevention - Linus Pauling Cure -- Vitamin C Lysine