Author Tim Ferriss has spent years studying how to improve the human body—he interviewed and trained with experts, studied scientific literature, and tried out what he learned on himself. In The 4-Hour Body, he distills the most effective 2.5% of what he discovered into programs you can use to improve six aspects of your body: losing fat and gaining muscle, enhancing sex, improving sleep, managing injuries, improving sports performance, and living longer.

Are spicy foods bad for you? Can sleep deprivation be fatal? In The Body, bestselling author Bill Bryson takes the reader on a whirlwind tour of the human body’s various systems. He examines how they work, how they can fail, and what can be done to fix them when that happens.

In this guide, we’ll focus on the practical takeaways from Bryson’s discussion and compare his advice to perspectives from other bestsellers, such as The Omnivore’s Dilemma, The 4-Hour Body, Why We Sleep, and How Not to Die. Along the way, you’ll learn why your sense of smell is probably as good as your dog’s, how hot peppers increase your life expectancy, and why you should let your teenager sleep in.

The Wisdom of Insecurity is philosopher Alan Watts’s 1951 treatise on the origins of and solutions to modern anxieties. According to Watts, we feel anxious because the only constant in life is insecurity—which means that seeking security is futile. He says that based on Eastern philosophies, we should embrace a more realistic approach to life—one where we accept insecurity and live in the moment instead of worrying about the future.

In this guide, we’ll explain what insecurity is, why it makes you anxious, and how you’re exacerbating your anxiety. We’ll also discuss the best—and worst—ways to cope with insecurity, according to Watts, who prefers Eastern religious concepts like unity and mindfulness over Christianity, science, and consumerism. In our commentary, we’ll cover other experts’ perspectives on insecurity, dig more deeply into the spiritual concepts underpinning Watts’s argument, and explore ways to put Watts’s advice into practice.

Do you feel like you’re getting the most out of your brain? Or do you struggle to tap into its immense power? In The Source, neurologist and professional adviser Tara Swart explains that to achieve your desires, you must tap into the full power of your brain. This means understanding how the brain changes itself in response to your experiences, the different modes of thinking, and the major principles of the Law of Attraction.

In our guide, we’ll explain Swart’s ideas about how to get the most out of your brain’s functioning to build the life you want. We’ll explore the concept of neuroplasticity and the modes of thinking that you need to tap into to maximize your brain’s potential. We’ll then explain the principles underlying the Law of Attraction. Finally, we’ll describe Swart’s four-step process for putting these ideas into action. We’ll add ideas from other writers on how to use your brain, as well as scientific context for Swart’s ideas and additional tips for applying them.

The Master Guide series is an original Shortform exclusive. We integrate the advice from every major book on a topic into a single, authoritative guide.

Do you wish you could better understand the ways people communicate with their body language? Nonverbal communication plays a huge role in how people express emotions and interact with each other. With an understanding of how to use and interpret body language, you can more easily form connections with others, adapt your nonverbal signals to suit different situations, and even alter your emotional state.

In Shortform’s Master Guide to Understanding and Using Body Language, we’ve collected insights from nine experts in nonverbal communication, including self-help authors, former FBI agents, behavioral experts, and leadership specialists. We’ll discuss how body language impacts our communication, as well as some of the most important contextual factors that should influence how we interpret nonverbal signals. Finally, we’ll look at a selection of nonverbal cues you can use to show others you’re open to friendship—and that may indicate whether or not others feel the same way.

How can you be more productive and creative? Most of us assume that the answer lies, at least in part, in managing our time better. But in Hyperfocus, productivity expert Chris Bailey presents an alternate hypothesis: To focus in a world full of ever-increasing distractions, you must learn not just how to manage your time but also how to manage your attention.

Bailey explains why your current method of directing your attention isn’t working—like why you still feel tired no matter how many breaks you take—and then shares several strategies for managing your attention for better productivity and creativity. In this guide, we’ll compare these strategies to recommendations from neuroscientists and other productivity experts, supplementing Bailey’s ideas so that you can manage your attention in the most effective way possible.

Meditations, by Roman emperor Marcus Aurelius, is one of the definitive texts on Stoicism. In Meditations, Aurelius shares his thoughts about the importance of logic over emotion and helps you to start training your mind to think rationally. By following Stoic teachings, you can live with purpose and die with dignity.

This translation by Gregory Hays is widely considered to be one of the best available. Hays, an associate professor of Classics, writes in plain, clear language that helps clarify some of the more obscure points of Meditations.

In today’s tech-dependent, app-centered, notification-ruled world, it’s easier than ever to get distracted from what’s really important—your values, your relationships, and your work. In Indistractable, Nir Eyal develops a four-part model for gaining the modern-day superpower of "indistractability."

You’ll learn how your distractions start internally, why your schedule should be based on your values instead of tasks, how to diminish the power of external triggers in your life, and how to commit to yourself—so you can start driving your life instead of letting its distractions drive you.

In The Power of Habit, Pulitzer Prize-winning journalist Charles Duhigg draws on extensive research to explore how habits develop into automatic behaviors that influence personal lives, businesses, and communities. He explains why unhealthy habits are notoriously difficult to break and provides a practical framework to help you understand and change any habit.

In this guide, we’ve restructured Duhigg’s key ideas to focus on how your habits form and what you can do to change them. We’ve also compared and contrasted each key concept with updated research on habit formation and expanded on Duhigg’s advice with actionable methods from other self-improvement authors and psychologists.

Why do you get up in the morning? What gives your life meaning and purpose? Many people can’t answer these questions. Even worse, they’re stuck in dysfunctional lifestyles that prevent them from ever finding out what their purpose is.

In Ikigai: The Japanese Secret to a Long and Happy Life, author and blogger Héctor García (author of A Geek in Japan) and novelist and self-help writer Francesc Miralles teach you to apply the Japanese concept of ikigai, or life purpose, to your own life. Drawing on lessons from the people of Okinawa, who live longer than anybody else on earth, as well as on insights from art, science, and psychology, they show you how to find and follow your own ikigai and cultivate a happy, healthy lifestyle to sustain it.