Possible Genetic Risks from Heat-Damaged DNA in Food

Abstract

The consumption of foods prepared at high temperatureshas beenassociated with numerous health risks. To date, the chief identifiedsource of risk has been small molecules produced in trace levels bycooking and reacting with healthy DNA upon consumption. Here, we consideredwhether the DNA in food itself also presents a hazard. We hypothesizethat high-temperature cooking may cause significant damage to theDNA in food, and this damage might find its way into cellular DNAby metabolic salvage. We tested cooked and raw foods and found highlevels of hydrolytic and oxidative damage to all four DNA bases uponcooking. Exposing cultured cells to damaged 2 '-deoxynucleosides(particularly pyrimidines) resulted in elevated DNA damage and repairresponses in the cells. Feeding a deaminated 2 '-deoxynucleoside(2 '-deoxyuridine), and DNA containing it, to mice resultedin substantial uptake into intestinal genomic DNA and promoted double-strandchromosomal breaks there. The results suggest the possibility of apreviously unrecognized pathway whereby high-temperature cooking maycontribute to genetic risks. Cooking foodat high temperature is found to damage DNAin foods. Incubating damaged DNA components with cells, or feedingthem to mice, results in damage to genomic DNA.