What Diabetes Is and Why Blood Glucose Matters

This lesson introduces diabetes as a condition in which blood glucose stays higher than the body can safely manage because insulin is missing, insufficient, or not working well. It explains how glucose normally moves from food and the liver into the bloodstream, how insulin helps glucose enter cells, and why persistent high glucose can affect energy, hydration, blood vessels, nerves, eyes, kidneys, heart, and overall health.

The lesson keeps the focus on foundational concepts: what blood glucose is, what insulin does, how type 1 and type 2 diabetes differ at a high level, and why glucose monitoring and treatment decisions matter. Detailed diagnosis, meal planning, medication options, technology, and long-term complication prevention are introduced only briefly and saved for later lessons.