mass murderer stress

Statistically speaking, stress is the biggest mass murderer of our time. It is the main cause of numerous diseases such as heart attacks, strokes and even cancer. According to a 2020 study by the World Health Organization (WHO), stress is now the biggest risk factor for premature mortality worldwide. But we live in a world with far fewer life-threatening influences than before - no saber-toothed tigers, fewer murders, wars and accidents, hardly any incurable diseases... and yet we are full of adrenaline, are constantly "on edge" and feel emotionally stressed - why? Shouldn't we all be able to walk happily and relaxed through our relatively super-safe Europe and simply enjoy our lives with a roof over our heads, a car in front of our door (or even two), always enough to eat and excellent healthcare, without worrying and releasing adrenaline? Where does the perceived stress come from and what does it cause in our bodies? What unhealthy processes are set in motion when we rush through our daily lives hectically and mindlessly or lose someone close to us (emotional stress)?