The study is reassuring, as previous recent evidence has suggested that consumption of very high levels of folate through supplements and from folate-fortified diet may increase risk of some cancers. Nonetheless, the potential importance of folate in colorectal cancer prevention remains in question because at least one other study found folate supplementation had no effect on recurrence of colorectal adenomas, precursors to colorectal cancer.
The study appears in Gastroenterology, and is the first to look at the association of folate with colorectal cancer risk with follow-up entirely after the mandatory fortification of the U.S. diet with folate. It also is the first to distinguish between the forms of folate found naturally in forms and folic acid, the form used for fortification and in supplements.
A research team led by Victoria Stevens, Ph.D., strategic director of laboratory services at the American Cancer Society, investigated the association between folate intake and colorectal cancer among 99,523 participants in the Cancer Prevention Study II Nutrition Cohort. A total of 1,023 participants were diagnosed with colorectal cancer between 1999 and 2007, a period entirely after folate fortification began. Neither higher nor lower risk was observed during the first two years of follow-up (1999 to 2001), but during 2002 to 2007, high folate intake was associated with a reduced risk of colorectal cancer.
"While folate fortification has been a public health success in reducing the risk of neural tube defects, the potential for an increase risk of cancer has been legitimate," said Dr. Stevens. "Our study population included many participants who consumed these very high levels of folate and we found no increased risk of colorectal cancer in these individuals. Nonetheless, one randomized clinical trial failed to show folate supplementation reduced the risk of adenomas, the non-cancerous colon polyps that can become cancerous, so we need to continue to investigate the influence of folate on cancer development in high risk populations as well as potential differences in the action of natural and synthetic form of this vitamin."
Article: High Levels of Folate From Supplements and Fortification Are Not Associated With Increased Risk of Colorectal Cancer; Victoria L. Stevens, Marjorie L. McCullough, Juzhong Sun, Eric J. Jacobs, Peter T. Campbell, Susan M. Gapstur; doi:10.1053/j.gastro.2011.04.004
Link to abstract: http://www.gastrojournal.org/article/S0016-5085(11)00475-6/abstract
David Sampson | EurekAlert!
A 'half-hearted' solution to one-sided heart failure
24.11.2017 | Boston Children's Hospital
New study points the way to therapy for rare cancer that targets the young
22.11.2017 | Rockefeller University
High-precision measurement of the g-factor eleven times more precise than before / Results indicate a strong similarity between protons and antiprotons
The magnetic moment of an individual proton is inconceivably small, but can still be quantified. The basis for undertaking this measurement was laid over ten...
Heat from the friction of rocks caused by tidal forces could be the “engine” for the hydrothermal activity on Saturn's moon Enceladus. This presupposes that...
The WHO reports an estimated 429,000 malaria deaths each year. The disease mostly affects tropical and subtropical regions and in particular the African continent. The Fraunhofer Institute for Silicate Research ISC teamed up with the Fraunhofer Institute for Molecular Biology and Applied Ecology IME and the Institute of Tropical Medicine at the University of Tübingen for a new test method to detect malaria parasites in blood. The idea of the research project “NanoFRET” is to develop a highly sensitive and reliable rapid diagnostic test so that patient treatment can begin as early as possible.
Malaria is caused by parasites transmitted by mosquito bite. The most dangerous form of malaria is malaria tropica. Left untreated, it is fatal in most cases....
The formation of stars in distant galaxies is still largely unexplored. For the first time, astron-omers at the University of Geneva have now been able to closely observe a star system six billion light-years away. In doing so, they are confirming earlier simulations made by the University of Zurich. One special effect is made possible by the multiple reflections of images that run through the cosmos like a snake.
Today, astronomers have a pretty accurate idea of how stars were formed in the recent cosmic past. But do these laws also apply to older galaxies? For around a...
Just because someone is smart and well-motivated doesn't mean he or she can learn the visual skills needed to excel at tasks like matching fingerprints, interpreting medical X-rays, keeping track of aircraft on radar displays or forensic face matching.
That is the implication of a new study which shows for the first time that there is a broad range of differences in people's visual ability and that these...
15.11.2017 | Event News
15.11.2017 | Event News
30.10.2017 | Event News
24.11.2017 | Physics and Astronomy
24.11.2017 | Health and Medicine
24.11.2017 | Earth Sciences