The modern diet was not designed to cause metabolic dysfunction. It evolved for convenience, shelf life, and palatability, and it happens to produce exactly the conditions in which insulin resistance develops. High-frequency eating, processed carbohydrates, meals with low fibre and high glycaemic load, and a near-complete absence of fasting periods all push the insulin system past the workload it was designed to manage. This post examines how contemporary eating habits interact with human biology and why the mismatch matters even for people who consider themselves relatively healthy.