Human Health and Disease is part of the Cambridge Modular Sciences series, developed in collaboration with the University of Cambridge Local Examinations Syndicate to support its A and AS level modular syllabuses. The books in the series can also be used with other syllabuses. Human Health and Disease studies the various factors related to health and disease in a global context.The effects on health of diet, exercise and drugs are discussed. Infectious diseases and the immune system are also studied in some depth. To help students with study and revision, there are self-assessment questions throughout the text, a list of learning objectives at the start of each chapter and a summary of contents at the end. Structured and essay questions also appear at the end of each chapter.