Japanese people are concerned about internal exposure to radiation through the consumption of contaminated food and water and external exposure due to environmental contamination. Using the coefficient of 0.05 Sv^-1 for the overall risk of dying from cancer and radiation doses derived from Cs-134, Cs-137 and I-131, the degree of exposure and risks were evaluated for different levels of radioactive contamination. Our results showed that the risk of internal exposure is less significant compared with that of external exposure in areas with relatively high dose rates, or so-called radioactive hot spots. Appropriate monitoring of radioactive contamination of food and disclosing the results are prerequisite for ensuring food safety and human health.