Overview6 copies each of all three reading levels, 18 books total. Health is not just about a person's diet, fitness, and genes. Life expectancy, or how long people are likely to live, is also a reflection of the society in which people live. A society's culture, politics, economy, and access to health care all have a tremendous impact on people's health. Health examines the positive changes taking place around the world. People are working to bring better access to doctors and nurses to improve everyone's health.