Kurzgesagt - In a Nutshell

Losing weight is hard, and obesity is one of the unhealthiest things that can happen to your body. It increases your risk of diabetes, heart attacks, cancer, and can lead to a series of other health complications. But today, the new weight loss drugs are changing people’s lives in a way no diet ever has before. They seem to melt fat away, reduce addiction and even prevent or reverse the negative effects of obesity. How do these drugs work? What do they do to our metabolism, and could they change public health forever?

Most of the universe is not made of stars, galaxies, or beautiful glowing nebulae. Instead, the majority of it is what seems to be vast, silent emptiness. Huge cosmic voids stretching hundreds of millions of light years across, containing almost nothing at all. But these dark regions are not just empty space. They are dynamic structures that grow, merge, and shape the entire architecture of the universe. What exactly are cosmic voids and how did they form? What makes them so strange, and what role might they play in the future of the universe?

At the height of the Cold War, nuclear weapons were seen not only as devices of destruction, but also as tools for progress. Project Plowshare was a bold attempt to use atomic explosions for more practical purposes: from digging canals and creating harbors to reshaping entire landscapes. This project was designed to push the limits of what seemed possible, but instead turned into an environmental disaster. How did Project Plowshare come up? What happened to it, and why did it fail in the end?

Your mind is the only place in the universe that only you can access. It’s where all of your thoughts, memories and emotions exist. A whole inner universe that is being shaped by your biology, experiences and imagination. It's what makes you: you. There is a wide spectrum of minds in nature, however humans have taken theirs to another level. Our minds can reflect on themselves, simulate other perspectives, and even construct entire fictional worlds. What exactly is a mind? How and why did it evolve, and could it be the most secret place in the universe?

Germany is heading towards a population collapse. For decades, birth rates have remained below replacement levels, while people are living longer than ever before. As a result, the population is now rapidly aging and facing a growing imbalance between the number of workers and retirees. This shift is putting pressure not only on Germany's pension system, but also on jobs, healthcare, and the services people rely on every day. So how did Germany get here and what will be the consequences? Is there a way to avoid this demographic collapse and if so, how?

Losing weight is hard, and obesity is one of the unhealthiest things that can happen to your body. It increases your risk of diabetes, heart attacks, cancer, and can lead to a series of other health complications. But today, the new weight loss drugs are often used to tackle the obesity. How do these drugs work? What do they do to our metabolism, and could they change public health forever? IMPORTANT: This is an updated version from the original video we released over a month ago. The first version did not contain wrong information but our framing was not good enough – after hearing your feedback it was clear that we didn’t communicate the topic well – so we revised the script, made the video longer and added more information and clarifications at key points.

Earth may seem like the perfect planet for life, but huge parts of our planet are actually hostile deserts of ice, rock, heat or darkness. Even our oceans are mostly barren voids where almost nothing can survive. But as we discover and research more exoplanets, we are beginning to wonder whether there could be worlds that are far better suited for life than Earth ever was, and where ecosystems flourish on a scale we can barely even imagine. Could there be a Super-Earth that is not just habitable, but truly ideal for life? What would such a world look like, and what kinds of creatures would we find there?

Memory is one of the strangest abilities you possess. Your brain uses an incredibly complex biological system to preserve moments from your past that no longer exist, allowing you to revisit experiences from years ago. But memories are not always recordings of reality. In fact, every time a memory comes under the spotlight of your attention, it can melt and change a tiny bit. What exactly is a memory, how is a moment in time stored inside your brain, and why does remembering something slowly rewrite the story of your life?

There is a hidden world filled with monsters you never heard of, from predators who spit acid and shoot harpoons, to armored hunters that devour their prey alive. Deep in the oceans, and even in fresh water from puddles and lakes, these microscopic super predators remained hidden in plain sight, and evolved over the last 2 billion years. What are the deadliest predators of the microworld, and what kind of bizarre biological weapons have they evolved over the past billions of years?