Vitamin B6 decreases risk of colorectal cancer

Jun 5 2005

According to a study published in the American Gastroenterological Association (AGA) journal Gastroenterology, women with a high dietary intake of vitamin B6 over several years have a decreased risk of colorectal cancer (CRC). Women who consume moderate to large amounts of alcohol in addition to vitamin B6 have more than a 70 percent reduced risk of developing CRC.

"Consuming a diet high in vitamin B6 may reduce the risk of colorectal cancer in women, more specifically those who consume alcohol," said Susanna Larsson, MSc, study author with the Karolinska Institutet. "Inadequate vitamin B6 status may lead to the development of cancerous polyps in the colon, so it is important for women to maintain a normal to high intake of vitamin B6."

The second-leading cause of cancer deaths in the United States, it is estimated that more than 28,000 women with CRC will die in 2005. While increased vitamin B6 consumption decreases the risk of colorectal cancer, it does not eliminate the need for regular screening. Guidelines of multiple agencies and professional societies underscore the importance of colorectal cancer screening for all individuals 50 years of age and older.

Researchers at the Karolinska Institutet in Stockholm, Sweden and the Harvard School of Public Health used data from the Swedish Mammography Cohort to evaluate the association between long-term dietary vitamin B6 intake from food sources and colorectal cancer risk, and its modification by alcohol consumption. Nearly 67,000 women, aged 40 to 75 years, responded to a questionnaire that solicited data on diet, family history of CRC and use of dietary supplements. Researchers observed that alcohol consumption in women with low vitamin B6 intake resulted in higher risk of developing colorectal cancer and that increasing intake reduces this risk significantly.

The recommended daily dietary intake of vitamin B6 for non-pregnant women in the United States is 1.3 to 1.5 mg. Vitamin B6 is found in a wide variety of foods, including fortified cereals, beans, meat, poultry, fish, and some fruits and vegetables. It performs a wide variety of functions in the body, including helping to maintain normal blood glucose levels, fighting off infections and creating hemoglobin to ensure that oxygen gets to important organs and tissues.

While the study shows that consuming high amounts of vitamin B6 reduces the risk of colorectal cancer in women who drink, researchers say findings need further confirmation in large prospective cohort or intervention studies.

"These findings may have important implications for the prevention of colorectal cancer in women who consume alcohol because their vitamin B6 status can be easily improved through dietary modifications, vitamin supplementation and fortification," said Larsson.