Highlights
Cancer
Growing evidence suggests that vitamins and micronutrients, especially from foods, may play important roles in the prevention or treatment of certain cancers:
- One study found that the risk of prostate cancer risk dropped as consumption of vegetables high in vitamin C, such as broccoli and bell peppers, rose.
- A diet high in cruciferous vegetables has been found to reduce the risk of kidney cancer; low consumption of cruciferous vegetables increases the risk.
On the other hand, high amounts of folic acid (a B vitamin) may be associated with colorectal cancer, and beta-carotene supplements are associated with increased lung cancer risk in smokers and people exposed to asbestos.
Macular Degeneration
In 2007, the National Eye Institute recommended that people with intermediate or advanced macular degeneration in one eye take a vitamin formula shown to reduce the risk of macular degeneration in the other eye by 25%. The formula contains vitamin C, vitamin E, beta-carotene, and zinc.
Osteoporosis
Vitamin K is widely used in Japan to treat osteoporosis, and studies suggest it also may be effective in treating rheumatoid arthritis.
Heart Disease
Although people with high levels of homocysteine are prone to developing blood clots in their arteries and veins, a 2007 study found that lowering homocysteine with B vitamins and folic acid does not reduce the incidence of deep vein thrombosis (DVT). A 2007 trial in adults with stable coronary artery disease found that lowering homocysteine levels 33% with folic acid and other B vitamins had no effect on arterial inflammation, meaning that lower levels were unlikely to offer protection against heart attack or stroke.
