By Jimmy Downs

Tuesday Oct 9, 2012 (foodconsumer.org) -- Taking folate or folic acid supplements may reduce risk of colorectal cancer, a study in Nutrition and Cancer suggests.  Colorectal cancer refers to both colon cancer and rectal cancer.

H.F. Clapin at The University of Western Australia in Crawley , Australia and colleagues conducted the study and found those who had used folate supplements for a long time were at 45 percent reduced risk for colorectal cancer.

Epidemiological studies have suggested folate may lower risk of colorectal cancer although studies are inconsistent with some pointing to the possibility that the naturally occurring dietary folate differs from the synthetic form of the vitamin folic acid.  

Folic acid and folate are often used interchangeably because it is assumed that their nutritional values are the same although chemically they are two different chemicals.

The current study is interesting.  The researchers wanted to examine how dietary folate and supplemented folic acid would be associated with risk of cancers on the left and right sides of the colorectum. Research has already suggested that cancers on the left side and on the right side are different in terms of their phenotypes and they may have different sets of risk factors, according to the researchers.

The population-based case-control study conducted in Western Australia involved 850 cases of colorectal cancer with 575 left-sided and 275 right-sided and 958 controls.

A statistical analysis showed that natural dietary folate intake was not associated with risk of either left-or right-sided colorectal cancer and use of folic acid supplements similarly did not seem to have a significant effect on right-sided colorectal cancer. 

However, individuals who had used folate supplements for more than 4 years had a 45 percent reduced risk of left-sided colorectal cancer, compared to those who had not taken folic acid supplements.

A significant trend in risk reduction was observed as duration of use increased.

Colorectal cancer is a common malignancy.  Folate is a vitamin found high in plant-based foods, particularly green vegetables.  Many processed foods are fortified with folate and too much fortified folate may not be good for a person's health, according to previous studies.