Nutrition and cancer
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Nutrition and cancer · Jan 2006
Colorectal cancer protective effects and the dietary micronutrients folate, methionine, vitamins B6, B12, C, E, selenium, and lycopene.
The data reported here were obtained from the case-control arm of a large, comprehensive, population-based investigation of colorectal cancer incidence, etiology, and survival, the Melbourne Colorectal Cancer Study, conducted in Melbourne, Australia. This part of the case-control study was designed to identify dietary factors associated with colorectal cancer risk in 715 incident cases compared with 727 age/sex frequency-matched randomly chosen community controls, in which a quantitative assessment of all foods eaten was made. New data are presented on the potential of two groups of micronutrients as protective agents, namely, those involved in DNA methylation, synthesis, and repair (folate, methionine, and vitamins B6 and B12) and those with antioxidant properties (selenium, vitamins E and C, and lycopene). ⋯ Lycopene was not associated with colorectal cancer risk. A combined model included vitamins E, C, and B12 and selenium as micronutrients protective for colorectal cancer and folate, which, however, showed an increased risk at the highest level of consumption. These data support the proposition that a diet containing the dietary micronutrients involved in DNA methylation (folate, methionine, and vitamins B6 and B12) and some of those with antioxidant properties (selenium and vitamins E and C) may have a role to play in lowering colorectal cancer risk and also that such protection can be achieved by dietary means alone.
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Nutrition and cancer · Jan 2006
Frequency of combined deficiencies of vitamin D and holotranscobalamin in cancer patients.
Vitamin D and holotranscobalamin (HTCII) deficiencies have been seen to demonstrate an association with various types of cancers. The objective of this study is to determine the frequency of vitamin D and HTCII deficiency in cancer patients. Our study investigated vitamin D, total B12, and HTCII levels in 70 cancer patients. ⋯ The standard measurement of total serum B12 alone is inadequate for identifying patients with insufficient levels of metabolically active B12. Deficiency of vitamin D (72%) and HTCII (34%) is prevalent among newly diagnosed patients with cancer and could play a role in cancer development and host response to tumor and therapy. Possible explanations for combined HTCII and 25(OH)D deficiencies include patient age, presence of atrophic gastritis, and lack of sun exposure.