What Is Type 5 Diabetes? Newly Recognised Diabetes Linked to Undernutrition

A newly recognised form of diabetes is reshaping how doctors and researchers understand the disease, particularly in countries like India where undernutrition remains a major public health challenge.

In 2025, global health experts formally recognised Type 5 diabetes as a distinct condition, ending decades of ambiguity around a form of diabetes that does not align with existing classifications. The move, supported by the International Diabetes Federation and recent findings published in The Lancet Global Health, is expected to influence diagnosis and care for millions worldwide.

How Type 5 Diabetes Is Different

Unlike Type 1 diabetes, which is caused by an autoimmune attack on insulin-producing cells, or Type 2 diabetes, which is commonly linked to obesity and lifestyle factors, Type 5 diabetes has its roots in severe undernutrition during childhood or adolescence.

During early life, the pancreas is still developing. Prolonged nutritional deprivation at this stage can permanently impair the organ’s ability to produce sufficient insulin. Years later, affected individuals develop high blood sugar levels despite being lean and lacking the typical risk factors associated with Type 2 diabetes.

For decades, such patients were often misdiagnosed as Type 1 or atypical Type 2 cases, resulting in treatments that were not always appropriate for their underlying condition.

Why Scientists Pushed for Official Recognition

Researchers in Asia and Africa have studied this condition for years, but the absence of formal classification meant it remained poorly understood and inconsistently managed. Experts argued that grouping these patients under existing diabetes types obscured the real biological cause of the disease.

The 2025 recognition formally separates Type 5 diabetes, enabling clearer research pathways, improved diagnosis, and the possibility of more tailored treatment approaches in the future.

Why This Matters for India

India faces a dual diabetes challenge. While obesity-linked diabetes continues to rise, undernutrition — especially in early life — remains widespread. Type 5 diabetes sits at the intersection of these two realities.

Many individuals develop diabetes not due to excess calories, but because their bodies never received enough nutrition during critical growth years. This makes Type 5 diabetes particularly relevant in the Indian context.

There is no immediate new treatment protocol for Type 5 diabetes. However, experts say recognition itself is a major breakthrough. Doctors can now approach lean diabetic patients with a history of childhood undernutrition more carefully, avoiding blanket treatment strategies.

Clearer classification is expected to improve long-term outcomes, reduce complications, and eventually guide more targeted care — an urgent need as India’s diabetes burden continues to grow.