Background: The earlier Atomic Bomb explosion in Hiroshima and Nagasaki, and three worth mentioning nuclear accidents - detonation at Fukushima Daiichi nuclear plant, Chernobyl nuclear fallout and an accident at Three Mile Island nuclear power plant have made us more worried about the secure exploitation of nuclear energy. The central focus of this paper is to review radiation-mediated health effects on human beings based on past and present incidences of nuclear detonations and/or accidents. Materials and Methods: The Data used in this review were mainly from PubMed and Medline in English, and recent data were taken from different types of renowned international organizations and newspapers. The study selection involves articles related to Fukushima nuclear detonation and radiation risks, health hazards due to radiation from Chernobyl nuclear fallout, Three Mile Island nuclear accident and radiation impacts and Atomic Bomb explosion and radiation-related health effects were selected. Results: The epidemiological studies based on past and present incidences of nuclear detonations and/or accidents entail both radiations mediated immediate and protracted effects and/or risks over human health. The individuals affected by radiation exposure, survivors of nuclear radiations and their subsequent generations are arrested by varying sorts of cancers and non-cancer diseases along with psychological implications and genetic disorders. Among the worst sufferers are pregnant women, fetus and children though it affects all ages and sexes of people. Conclusion: Since the safely and peaceful usage of nuclear energy is in question, today’s global health is at risk and none of us free from it.