In this course, we’ll look at the facts and misconceptions around obesity and discuss key physiological and psychological concepts around the brain’s control of appetite and body weight. We’ll consider the biological and environmental pressures that make it easy to gain weight (and hard to lose it!). Most importantly, we'll give you the opportunity to reflect on your own knowledge and assumptions around the subject. We deliver course materials as a mixture of videos, audio-only MOOCcasts, and a selection of short readings. There are short weekly quizzes, a peer-reviewed exercise, and discussion activities on the forum. These will help you prepare for the final project. In it, you are invited to demonstrate your evidence-informed understanding and express how you'll develop it beyond the course. The course features Citizen Science projects. We'll collect data from you (anonymously, of course) and use it to drive participant-led discussions of controversial ideas. In this way, we hope to explore ideas around diet and obesity. These projects also give a taste of how scientific evidence is collected and interpreted by scientists, and give some indication how much there still is to discover and understand.