Basic Research
Copyright ©2006 Baishideng Publishing Group Co., Limited. All rights reserved.
World J Gastroenterol. Jan 14, 2006; 12(2): 222-227
Published online Jan 14, 2006. doi: 10.3748/wjg.v12.i2.222
Peanut consumption and reduced risk of colorectal cancer in women: A prospective study in Taiwan
Chih-Ching Yeh, San-Lin You, Chien-Jen Chen, Fung-Chang Sung
Chih-Ching Yeh, Department of Risk Management, China Medical University College of Public Health, Taichung 404, Taiwan, China
San-Lin You, Chien-Jen Chen, Institutes of Epidemiology, National Taiwan University College of Public Health, Taipei 100, Taiwan, China
Fung-Chang Sung, Institute of Environment Health, China Medical University College of Public Health, Taichung 404, Taiwan and Institute of Environment Health, National Taiwan University College of Public Health, Taipei 100, Taiwan, China
Supported by the Grant NSC 2000-2314-B-002-373, NSC 2001-2320-B-002-123 and NSC 2002-2320-B-002-121 from the National Science Council, Taipei, Taiwan, China
Correspondence to: Fung-Chang Sung, PhD, MPH, Professor and Director, Institute of Environment Health, China Medical University College of Public Health, 91 Hsueh-Shih Road, Taichung 404, Taiwan, China. fcsung@mail.cmu.edu.tw
Telephone: +886-4-2205-4070 Fax: +886-4-2201-9901
Received: June 13, 2005
Revised: June 28, 2005
Accepted: July 8, 2005
Published online: January 14, 2006
Abstract

AIM: To examine whether peanut consumption is associated with a reduced risk of colorectal cancer in a prospective cohort with a 10-year follow-up.

METHODS: In 1990-1992, residents (12 026 men and 11 917 women aged 30 to 65 years) in 7 townships, Taiwan, were interviewed and recruited into a cancer-screening cohort and annually followed up. Colorectal cancer cases in this cohort were identified from cancer registry and death certificates. Incidence rates of this disease by the end of 2001 were calculated by gender for the primary study variable and covariates. The dietary intake was assessed by means of weekly food frequency measures, including frequently consumed food groups and folk dishes including sweet potato, bean products, peanut products, pickled foodstuffs, nitrated or smoked foodstuffs.

RESULTS: During the study period, 107 new colorectal cancer cases (68 men and 39 women) were confirmed. The multivariate Cox’s proportional hazard model showed that the relative risk (RR) of peanut consumption was 0.73 [95% confidence interval (CI) = 0.44-1.21] for men and 0.42 (95% CI = 0.21-0.84) for women. However, frequent intake of pickled foodstuffs was harmful for women (RR = 2.15, 95% CI = 0.99-4.65). The risk of colorectal cancer was also elevated among cigarette smokers but not significant (P < 0.05).

CONCLUSION: This study suggests that frequent intake of peanut and its products may reduce colorectal cancer risk in women, demonstrating the anti-proliferating effect of peanut intake.

Keywords: Peanuts; Colorectal cancer; Diet; Gender difference; Prospective study; Taiwan