Featured Research

from universities, journals, and other organizations

Risks And Benefits Of Folic Acid Fortification Considered

Date:
July 13, 2007
Source:
Tufts University, Health Sciences
Summary:
Researchers report a temporal relationship between nationwide folic acid fortification and an increase in rates of colorectal cancer. Their analysis and resulting hypothesis adds to ongoing debate and suggests further research on total population effects of fortification.

Since the institution of nationwide folic acid fortification of enriched grains in the mid 1990s, the number of infants born in the United States and Canada with neural tube defects has declined by 20 percent to 50 percent. Concurrent with the institution of fortification, however, the rate at which new cases of colorectal cancer were diagnosed in men and women increased, report researchers at the Jean Mayer USDA Human Nutrition Research Center on Aging (USDA HNRCA) at Tufts University.

Joel Mason, MD, director of the USDA HNRCA's Vitamins and Carcinogenesis Laboratory, and colleagues analyze the temporal association between folic acid fortification and the rise in colorectal cancer rates, and present their resulting hypothesis in an article in the July issue of Cancer Epidemiology Biomarkers & Prevention.

"Nationwide fortification of enriched grains is generally considered one of the greatest advances in public health policy," says Mason, who is also an associate professor at the Friedman School of Nutrition Science and Policy at Tufts. "But since the time that the food supply in North America was fortified with folic acid, we have been experiencing four to six additional cases of colorectal cancer for every 100,000 individuals each year compared to the trends that existed before fortification.

"Our analysis suggests that this increase is not explained by chance or by increased cancer screening. Therefore, it is important to analyze risks and benefits of fortification, and encourage scientific debate in countries that are considering instituting or enhancing folic acid fortification."

Mason and colleagues analyzed data from national cancer registries, one in the United States and another in Canada. The US data were derived from the nationwide Surveillance Epidemiology and End Results (SEER) registry that publishes cancer occurrence rates and survival data, covering approximately 26 percent of the population. The Canadian data were obtained from Canadian Cancer Statistics, an annual publication by the Canadian Cancer Society and the National Cancer Institute of Canada.

In 1996 and 1998, there were abrupt reversals in the 15-year downward trends in colorectal cancer rates in the United States and Canada, respectively. Since peaking in 1998 in the United States and in 2000 in Canada, the rates have not returned to their earlier levels. Although folic acid fortification of enriched grains -- including bread, cereal, flour, rice, and pasta -- did not become mandatory until 1998, large food companies began voluntary fortification in 1996, first in the United States and later in Canada.

Folic acid is the synthetic form of folate, a B vitamin that is essential for cell growth. After intestinal absorption, folic acid is converted to methyltetrahydrofolate, found naturally in foods such as leafy green vegetables, legumes and citrus fruits. "The body's response to folic acid appears to be complex," says Mason. "While fortification of the food supply is clearly beneficial for women of child-bearing age and their offspring, it is possible that it may, coincidentally, be linked to the increase in colorectal cancer rates. Our report is intended to create a foundation upon which to further explore that possibility."

As Mason and colleagues note, there is a compelling body of scientific evidence suggesting that habitually high intakes of dietary folate are protective against colorectal cancer. Mason explains, however, that "There are several reasons why we may have inadvertently created the opposite effect with folic acid fortification. First, folate's pivotal role in DNA synthesis also makes it a potential growth factor for cancerous or pre-cancerous cells, and when administered in large quantities to individuals who unknowingly harbor cancer cells, it could paradoxically enhance cancer development.

The addition of substantial quantities of folic acid into the foodstream may have facilitated the transformation of benign growths into cancers, or small cancers into larger ones," he says. "Second, the fact that a synthetic form of folate is used for fortification may be important," suggests Mason. "As the total amount of folic acid ingested increases, the mechanism that converts folic acid to methyltetrahydrofolate can become saturated. The leftover folic acid in the circulation might have detrimental effects, as it is not a natural form of the vitamin."

At a time when many countries are debating whether or not to institute or enhance folic acid fortification, Mason and colleagues urge caution and debate. "We must examine the effects of folic acid fortification on the population as a whole, which includes better defining the nature of the relationship between folic acid fortification and colorectal cancer," says Mason. "Improved monitoring and further research in this field is important to our understanding of the long-term public health effects of fortification."

Reference: Mason JB, Dickstein A, Jacques PF, Haggarty P, Selhub J, Dallal G, Rosenberg IH. Cancer Epidemiology Biomarkers & Prevention. 2007 (July); 16(7):1-5. "A Temporal Association between Folic Acid Fortification and a Rise in Colorectal Cancer Rates May be Illuminating Important Biological Principles: a Hypothesis."


Story Source:

The above story is based on materials provided by Tufts University, Health Sciences. Note: Materials may be edited for content and length.


Cite This Page:

Tufts University, Health Sciences. "Risks And Benefits Of Folic Acid Fortification Considered." ScienceDaily. ScienceDaily, 13 July 2007. <www.sciencedaily.com/releases/2007/07/070710064813.htm>.
Tufts University, Health Sciences. (2007, July 13). Risks And Benefits Of Folic Acid Fortification Considered. ScienceDaily. Retrieved September 23, 2014 from www.sciencedaily.com/releases/2007/07/070710064813.htm
Tufts University, Health Sciences. "Risks And Benefits Of Folic Acid Fortification Considered." ScienceDaily. www.sciencedaily.com/releases/2007/07/070710064813.htm (accessed September 23, 2014).

Share This



More Health & Medicine News

Tuesday, September 23, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Ebola Costs Keep Mounting

Ebola Costs Keep Mounting

Reuters - Business Video Online (Sep. 23, 2014) The WHO has warned up to 20,000 people could be infected with Ebola over the next few weeks. As Sonia Legg reports, the implications for the West African countries suffering from the disease are huge. Video provided by Reuters
Powered by NewsLook.com
Liberia Pleads for Help to Fight Ebola

Liberia Pleads for Help to Fight Ebola

AP (Sep. 22, 2014) Liberia's finance minister is urging the international community to quickly follow through on pledges of cash to battle Ebola. Bodies are piling up in the capital Monrovia as the nation awaits more help. (Sept. 22) Video provided by AP
Powered by NewsLook.com
Ebola Doctor Says Border Controls Critical

Ebola Doctor Says Border Controls Critical

AP (Sep. 22, 2014) A Florida doctor who helped fight the expanding Ebola outbreak in West Africa says the disease can be stopped, but only if nations quickly step up their response and make border control a priority. (Sept. 22) Video provided by AP
Powered by NewsLook.com
Global Ebola Aid Increasing But Critics Say It's Late

Global Ebola Aid Increasing But Critics Say It's Late

Newsy (Sep. 21, 2014) More than 100 tons of medical supplies were sent to West Africa on Saturday, but aid workers say the global response is still sluggish. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Health & Medicine

Mind & Brain

Living & Well

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins