Vitamin C had anti-cancer effects in cells, cut cancer-cell growth, lowered inflammation, reduced cell damage in type 1 diabetics after exercise and eased blood pressure in several recent studies.
The body normally forms new blood vessels to grow and repair itself in a process called angiogenesis, but in cancer, the specialized cells (endothelial) that line blood vessels can feed tumors. In this lab study, doctors found that high concentrations of vitamin C (200 to 300 mg per deciliter of blood) slowed the growth and spread of endothelial cells. In a related cancer lab study, high concentrations of vitamin C curbed the inflammatory proteins (COX-2) that promote growth in melanoma cells.
In a study of inflammation, about 400 healthy non-smokers, some with high levels of an inflammatory protein (C-reactive protein or CRP), took 1,000 mg of vitamin C per day or a placebo. After two months, those with high CRP in the vitamin C group had 17 percent lower CRP levels compared to placebo. Doctors noted that vitamin C improved CRP as effectively as statin drugs and that vitamin C may be a better alternative for those with high CRP because of statin drug side effects.
In a diabetes exercise study, doctors noted that those with type 1 diabetes may have more cell damage from exercise than healthy people. Researchers gave 12 type 1 diabetics and 12 healthy participants 1,000 mg of vitamin C or a placebo and then measured cell damage (oxidative stress) before and after hard exercise. The diabetics had higher levels of oxidative stress than the healthy folks at the start of the study. After exercise, oxidative stress levels were lower in both diabetics and non-diabetics compared to placebo.
In a blood pressure study, researchers followed 242 black and white women, aged 18 to 21, for 10 years and found that systolic and diastolic blood pressure were significantly lower in those with the highest blood levels of vitamin C compared to those with lower levels.
American Journal of Cell Physiology; 2008, Vol. 216, No. 1, 180-8.