Prof Elio Riboli, at Imperial College London (England), looked at the preventive potential of vitamin D and calcium on colorectal cancer risk.
The research found that higher blood concentrations of vitamin D are inversely related to the risk of colorectal cancer. This association was found to be more apparent in colon cancer than rectal cancer. No association was observed for dietary vitamin D intake.
H. Bas Bueno-de-Mesquita, at University Medical Centre Utrecht (Netherlands), examined the association between antioxidant levels in blood and colorectal cancer risk.
This research found an association between higher blood levels of vitamin A and a lower risk of developing colorectal cancer, particularly of those cancers originating in the large intestine. Higher levels of vitamin A precursors (α- and β-carotene) were also associated with a lower risk of cancer in the large intestine but, surprisingly, higher levels of α-carotene were associated with an increased risk of cancers originating in the rectum.
Maria Velasco-Garcia, at The Open University in England, investigated the hypothesis that vegetarian diets help reduce cancer risk by reduction of DNA damage levels.
The research established a new analytical method for the measurement of DNA adducts related to high red meat diets. Despite low levels of these DNA adducts have proven to in urine, there is strong evidence that the adducts are indeed formed. Further studies will be required to analyse a larger number of samples.