Year after year, conditions, quality, and duration of human lives have been improving due to the progress of science, technology, education, and medicine, which however has a downside. Owing to improvement in children’s nutrition, developmental acceleration occurs that imbalances a child’s system. Because of virtual worlds of the Internet, social experience of teenagers expands and clashes with puberty of adolescents. Due to the comfort of cities, urbanization emerges and causes stress to adults because of artificial light, noise, pollution, violations of personal space, and family disruption. At old age, all these factors taken together contribute to loneliness, cancer, diabetes, drug addiction, and sporadic Alzheimer’s disease, which shorten the lifespan, as reviewed in the US, 1990–2010. That is why, a person may ask oneself: “What can I do now to keep my health in my old age?” To help them, we provide this comprehensive review on predictive preventive personalized medicine. This branch of molecular medicine uses single nucleotide polymorphisms to prevent diseases on the basis of the difference between the individual and reference human genomes.