Here's to a better you. For people interested in self-improvement, the world can be a confusing place. Diet and exercise fads come and go, health advice changes and foods that were good for you last week are suddenly bad for you - and there are hundreds if not thousands of magazines, newspaper articles and self-improvement books all claiming to know the one true path to a better you.How to supercharge your brain and get smarter. What not to eat - demystifying some of the most contentious issues in nutrition science. Grow old gracefully. Learn the recipes for success. And more.This issue of New Scientist: The Collection, a compilation of classic articles from New Scientist, is dedicated to giving you the tools to live a better life, all based on scientific evidence.