Navigation Links
Vitamins C and E and beta carotene again fail to reduce cancer risk in randomized controlled trial
Date:12/30/2008

Women who took beta carotene or vitamin C or E or a combination of the supplements had a similar risk of cancer as women who did not take the supplements, according to data from a randomized controlled trial in the December 30 online issue of the Journal of the National Cancer Institute.

Epidemiological studies have suggested that people whose diets are high in fruits and vegetables, and thus antioxidants, may have a lower risk of cancer. Results from randomized trials that address the issue, however, have been inconsistent and have rarely supported that observation.

In the current study, Jennifer Lin, Ph.D., of the Brigham and Women's Hospital and Harvard Medical School in Boston, and colleagues tested the impact of antioxidant supplements on cancer incidence in a randomized controlled trial. A total of 7,627 women who were at high risk of cardiovascular disease were randomly assigned to take vitamin C, vitamin E, or beta-carotene.

With an average of 9.4 years of follow-up time, there was no statistically significant benefit from antioxidant use compared with placebo in terms of disease risk or mortality due to cancer. Overall, 624 women developed cancer and 176 died from cancer during the follow-up time. Compared with placebo, the relative risk of a new cancer diagnosis was 1.11 for women who took vitamin C, 0.93 for women who took vitamin E, and 1.00 for women who took beta carotene. None of these relative risks was statistically significantly different from 1.

"Supplementation with vitamin C, vitamin E, or beta carotene offers no overall benefits in the primary prevention of total cancer incidence or cancer mortality," the authors conclude. "In our trial, neither duration of treatment nor combination of the three antioxidant supplements had effects on overall fatal or nonfatal cancer events. Thus, our results are in agreement with a recent review of randomized trials indicating that total mortality was not affected by duration of supplementation and single or combined antioxidant regimens."

In an accompanying editorial, Demetrius Albanes, M.D., of the National Cancer Institute, reviewed data from previous randomized controlled trials that examined supplement use and cancer incidence. He noted that while the trial data reported by Lin are negative with respect to lowering cancer risk, there is valuable information uncovered that should not be overlooked. There was a trend for a reduction in colon cancer with vitamin E supplementation, which has been observed in other studies. Additionally, beta carotene use was associated with a modest excess of lung cancer, which is consistent with previous reports.

"Null trials or those with unexpected outcomes should not, however, be viewed as failures; they have and will continue to shed light on the causes of cancer and help us discover the means for its prevention," the editorialist concludes.


'/>"/>

Contact: Caroline McNeil
jncimedia@oxfordjournals.org
301-841-1287
Journal of the National Cancer Institute
Source:Eurekalert

Related biology news :

1. Calcium and vitamin D may not be the only protection against bone loss
2. A novel target for therapeutics against Staph infection
3. Researchers recreate SARS virus, open door for potential defenses against future strains
4. In the war against diseases, nerve cells need their armor
5. A new weapon in the fight against obesity and diabetes
6. Global methane levels on the rise again
7. Severe gestational hypertension may protect against testicular cancer
8. Methane gas levels begin to increase again
9. Gene against bacterial attack unravelled
10. Purple tomatoes: The richness of antioxidants against tumors
11. Research identifies type of vaccine that holds promise in protecting against TB
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:4/15/2016)... , April 15, 2016  A new partnership ... more accurate underwriting decisions in a fraction of ... competitively priced and high-value life insurance policies to ... With Force Diagnostics, rapid testing (A1C, ... data readings (blood pressure, weight, pulse, BMI, and ...
(Date:3/31/2016)... RATON, Florida , March 31, 2016 ... LEGX ) ("LegacyXChange" or the "Company") ... for potential users of its soon to be launched ... video ( https://www.youtube.com/channel/UCyTLBzmZogV1y2D6bDkBX5g ) will also provide ... the use of DNA technology to an industry that ...
(Date:3/22/2016)... PUNE, India , March 22, 2016 ... new market research report "Electronic Sensors Market for ... Fingerprint, Proximity, & Others), Application (Communication & ... and Geography - Global Forecast to 2022", ... consumer industry is expected to reach USD ...
Breaking Biology News(10 mins):
(Date:5/4/2016)... San Diego, CA (PRWEB) , ... May 04, ... ... Mother’s Day? Well, look no further than LaJollaCooks4u, San Diego’s premiere hands-on cooking ... everything you need to give mom an experience she won’t forget. , Guests ...
(Date:5/4/2016)... ... May 04, 2016 , ... PBI-Gordon Corporation is pleased to ... , Doug began his career at PBI-Gordon in February 1988, after finishing his ... variety of roles, ranging from customer service to national product manager, to helping develop, ...
(Date:5/3/2016)... Massachusetts (PRWEB) , ... May 03, 2016 , ... ... will gather at Boston CEO 2016 on May 31st and June 1st at ... networking forum for leading executives in the life sciences, offering exclusive access to ...
(Date:5/3/2016)... , May 3, 2016  Dr. Thomas ... surgeon in The Woodlands, Texas , ... 24 percent of treated fat cells in just 25-minutes, ... Close to 90 percent of Americans report feeling bothered ... Nonsurgical fat reduction procedures are a growing industry. This ...
Breaking Biology Technology: