What is Diabetes Mellitus?

Diabetes mellitus is the condition where blood sugar stays too high because the body cannot make enough insulin or cannot use it well. India carries one of the world's largest diabetes burdens - and the disease is far more manageable than its reputation when caught early and treated steadily.

What is actually happening

Every meal breaks down into glucose - the body's basic fuel. Insulin is the key that lets glucose out of the blood and into cells. In diabetes, either the key is missing (the pancreas stops making insulin) or the locks are rusty (cells resist insulin). Glucose piles up in the blood, and over years the excess sugar quietly damages eyes, kidneys, nerves, heart and feet.

The three faces

• Type 1: the immune system destroys the insulin-making cells - begins usually in childhood or youth, needs insulin for life; not caused by anything anyone did
• Type 2: the lifestyle-linked epidemic - the body resists insulin, then the pancreas tires; linked to weight around the belly, inactivity, family history and age, and increasingly hitting Indians in their 30s and 40s
• Gestational: diabetes appearing in pregnancy - usually resolves after delivery but raises future type 2 risk for mother and child

Why India worries specifically

Indians develop diabetes earlier and at lower body weights than Western populations - the "thin-fat" pattern: slim-looking outside, visceral fat inside. A belly that outgrows the belt is a diabetes risk sign even in a thin person.

The hopeful truth

Prediabetes - the warning stage - is reversible with food, movement and modest weight loss. Established diabetes is controllable to the point of a full, normal life. The complications everyone fears belong mostly to neglected sugar, not treated sugar.

One-line summary

Diabetes is glucose stuck in the blood for want of insulin's key - type 1 needs insulin for life, type 2 is India's lifestyle epidemic, prediabetes is reversible, and steady treatment is what separates a normal life from the complications.