Search Foodconsumer & Others
Newsfeed
Su
bmit news[release]
More than 100 credit cards available at uscards.com 
|
|
|
Last Updated: Nov 18, 2008 - 8:00:45 AM |
Vitami.n C lowers bloo.d pressur.e
Tuesday November 18, 2008 (foodconsumer.org) -- A new study scheduled to be presented Sunday at an American Academy of Cancer Research (AACR) meeting in Washington, D.C. suggests that taking vitamin E and vitamin C may not provide any protective effect against cancer.
The Physicians' Health Study II, a randomized clinical trial, involved 14, 641 physicians age at least 50 at enrollment. Participants were given 400 IU of vitamin E or 500 mg of vitamin C or a placebo each day for up to 10 years.
Researchers did not see a protective effect of vitamin E against prostate cancer, which afflicts about 200,000 men in the United States each year. Nor any effect of this vitamin was found to reduce risk of any other cancer. Vitamin C was just like vitamin E giving no protection against total cancer.
The results of the study are almost the same as the results of another study published in the Feb 2006 issue of Journal of National Cancer institute.
In that survey-type study, Kirsh VA and colleagues of the National Cancer Institute followed up men 29,000 men for 8 years during which 1338 cases of prostate cancer were recorded.
The researchers found no association between prostate cancer risk and dietary or supplemental intake of vitamin E or vitamin C whatsoever. But among recent smokers in the past 10 years, the risk of advanced prostate cancer was reduced by about 70 percent in those who took 400 IU per of vitamin E supplement. Longer duration of taking the vitamin was also linked with a significantly decreased risk.
"After nearly 10 years of supplementation with either vitamin E or vitamin C, we found no evidence supporting the use of either supplement in the prevention of cancer," said Howard D. Sesso, Sc.D., M.P.H., coauthor of the current study at Brigham and Women's Hospital.
"While vitamin E and C supplement use did not produce any protective benefits, they also did not cause any harm," he added.
Some studies have found that people who reported eating a diet rich in vitamins E and C had a lower risk of cancer and taking these vitamins as individual supplements may also offer some protective benefits.
But studies are always inconsistent. Some previous studies have suggested taking vitamin E and C supplements may not provide any protection
Study co-author J. Michael Gaziano, M.D., M.P.H., associate professor of medicine at Brigham and Women's Hospital and VA Boston said, "Individual vitamin supplements such as vitamin E and C do not appear to provide the same potential advantages as vitamins included as part of a healthy, balanced diet."
Some other studies suggest that it is likely that vitamin E and C, antioxidant vitamins may play a role in the carcinogenesis in the prostate gland.
One study published by Surapaneni KM, and Ramana V. in the APril-Jun 2007 issue of Indian Journal of Physiology and Pharmacology showed that the levels of erythrocyte ascorbic acid and plasma vitamin E levels were lower in patients with carcinoma of prostate suggesting that prostate cancer has something to do with vitamin E and C.
A health observer cautioned that consumers should ensure they have enough intakes of vitamin E and vitamin C no matter what conclusions resulted from this and other studies. After all, these are vitamins, meaning they are vital to your life.
He said a couple of things needs be considered. For one thing, it is unclear what form of vitamin E the study participants took and how well they adhered to the dietary intervention. Not all forms of vitamin E are equally effective and not all participants could take the vitamins each day for 10 years. Also dosages may also determine the efficacy.
However, the health observer suggested that people should not solely rely on vitamin supplements and natural sources of vitamin E and C should be preferred for prevention of prostate cancer and other diseases. Natural vitamin E like alpha-tocopherol is found abundant in vegetable oils and nuts like almonds, hazelnuts and peanuts among others. Vitamin C is found in a variety of fruit and vegetables.
Also people may want to be aware that the term vitamin E could apply to a family of eight antioxidants: four tocopherols (alpha-, beta-, gamma-, and delta-) and four tocotrienols (alpha-, beta-, gamma-, and delta-), according to Linus Pauling Institute. But only alpha-tocopherol is actively maintained in the human body and thus probably is the most important form.
© 2004-2008 by foodconsumer.org unless otherwise specified
Top of Page
Search Consumer-friendly Health Sites
|
|
|
|