Trial Information

Inhibition of Fried Meat-Induced DNA Damage: A Dietary Intervention Study

Dietary exposures have been implicated as risk factors in colorectal cancer. Such agents
may act by causing DNA damage or may be protective against DNA damage. The effect of
dietary exposures in either causing or preventing damage has not been directly assessed in
colon tissues. We are proposing a pilot study of dietary factors and DNA damage, involving
16 healthy volunteers in a four-week controlled feeding study. The primary focus of this
study is to assess genetic damage to colonic epithelium and blood lymphocytes induced by
pyrolysis products formed in cooked meat, as well as the putative protective effects of
cruciferous vegetables, yogurt, and chlorophyllin against that damage. In the first phase
of this pilot study, eight subjects will be fed either a baseline diet or a diet high in
fried meat in two-week intervals. In the second phase, the remaining eight subjects will be
fed either the fried meat diet or a diet containing fried meat along with putative
inhibitors. In both phases of the study, blood will be drawn and rectal biopsies will be
obtained from subjects each week during the four-week study periods. Damage in the
lymphocytes and colon epithelium from the different dietary regimens will be evaluated using
the single cell gel electrophoresis (comet) assay. Rectal biopsies used in this study are
painless and generally without risk. In previous studies conducted by Dr. Robert Sandler,
at UNC, over 2,000 rectal biopsies have been obtained without any adverse events. The goal
of this study will be to determine the feasibility of conducting a larger study to examine
the interaction of genotoxic components in fried meat with "protective" dietary factors on a
molecular level.