After a century of futility, the seemingly impenetrable mystery of weight loss is nearly solved. Until late 2022, most of us were taught that the weight loss journey was paved with willpower. Our Sisyphean task was to create a caloric deficit through diet and exercise and maintain it indefinitely through deliberate effort, food, and activity tracking, and enduring lifestyle changes. For the minority, this formula succeeded.1 Yet most people found that weight loss was a revolving door: No matter the method or the motivation, their weight eventually returned to roughly the same starting point.2 Then something unexpected happened. Following decades of clinical trials yielding ineffective or even dangerous weight loss medicines,3 a new class of injectable medicines called GLP-1 agonists (GLP=glucagon-like peptide) arrived in 2022-2023.4 Not only did the average GLP-1 user experience weight loss far surpassing that usually achieved through lifestyle changes alone, their weight loss generally came with minimal conscious effort. For the first time, people were suddenly achieving clinically significant weight loss without tracking calories, practicing specific diets, or willpowering themselves through …