Why did you come to ? fluticasone furoate nasal spray buy The book is broken into three parts. The first part is a brief history of humanity through five ages of existence — Animal, Paleolithic, Agricultural, Industrial, and Information. Each of these stages provides lessons for how we can be healthier today. The second part looks at how we can apply these lessons to "multiple areas of modern-day life: food, fasting, movement, bipedalism (standing, walking, running), temperature, sun and sleep." The book wraps up with a speculative vision of how our ancient hunter and gatherer roles can inspire us to build healthy lifestyles.