Inverse associations between serum concentrations of zeaxanthin and other carotenoids and colorectal neoplasm in Japanese

Background To investigate the associations between serum concentrations of carotenoids and the presence of colorectal polyps and cancers in Japanese using a cross-sectional study. Methods 893 subjects who underwent colorectal endoscopy between 2001 and 2002 provided serum samples and information on lifestyle factors. Serum concentrations of six carotenoids were compared among patients with polyps, cancers, and controls. Results In males, high serum zeaxanthin was associated with decreased rates of polyps [odds ratio (OR) = 0.48, 95 % confidence interval (CI) 0.27-0.87] and cancer (OR = 0.35, 95 % CI 0.12-1.06), adjusting for age, body mass index, serum cholesterol, smoking status, and alcohol intake. In females, zeaxanthin (OR = 0.25, 95 % CI 0.07-0.82), lutein (OR = 0.30, 95 % CI 0.10-0.94), alpha-carotene (OR = 0.30, 95 % CI 0.10-0.90), and beta-carotene (OR = 0.27, 95 % CI 0.09-0.85) showed significant inverse associations with cancer development. These associations were consistent with findings of inverse associations between the ingestion of green-yellow vegetables (OR = 0.44, 95 % CI 0.23-0.84), carrots and pumpkins (OR = 0.46, 95 % CI 0.25-0.86), and fruits (OR = 0.53, 95 % CI 0.30-0.94) and polyp in males, and between carrots and pumpkins (OR = 0.30, 95 % CI 0.09-0.99), legumes (OR = 0.14, 95 % CI 0.04-0.44), and seaweed (OR = 0.23, 95 % CI 0.07-0.75) and cancer development in females. Conclusions These results provide further support for the protective effects of carotenoids contained in green-yellow vegetables and fruits against colorectal neoplasm in Japanese.