The aim of this work was to evaluate, by comet assay, the possible inducing of DNA lesions in peripheral blood mononuclear cells of rats subjected to acute or chronic food deprivation. Wistar male rats were subjected to 72 h of partial (50%), or total acute food deprivation, and then allowed to recover for different time periods (24, 48 and 72 h). In other experiments, comet scores were determined in peripheral blood mononuclear cells of rats subjected to chronic food deprivation (25% and 50%) for 50 days. Blood aliquots were obtained before, during and after food deprivation. Comet assay was carried out, the comet units photographed and scored (class 0 up to 3). Acute and chronic food-deprived rats presented peripheral blood mononuclear cells with DNA lesions (comet classes 1, 2 and 3) and a significant increase (p<0.05) in the number of comet units compared with its basal level. The increase was proportional to acute food deprivation time, but after being taken off, it progressively returned to basal level after 48 h (partial group) or 72 h (total group). Chronic food-deprived rats presented a progressive increase of comet score up to 5 days, and a decrease thereafter to reach a basal level. Possible mechanisms of DNA lesions are discussed.