IDF Officially Recognizes Type 5 Diabetes

The International Diabetes Federation (IDF) has officially recognized type 5 diabetes, a distinct form of the disease linked to chronic undernutrition and health disparities. Previously known as malnutrition-related diabetes mellitus (MRDM), this classification was formally established during an international meeting of experts in January 2025 and subsequently endorsed by the IDF at the World Diabetes Congress 2025 in Bangkok, Thailand.

Type 5 diabetes is now acknowledged as the fifth major classification of diabetes, joining type 1, type 2, type 3c, and gestational diabetes. This recognition aims to address a long-overlooked condition that primarily affects individuals in low- and middle-income countries (LMICs), with a high prevalence in South-East Asia and sub-Saharan Africa.

Causes and Pathophysiology

Unlike type 2 diabetes, which is associated with obesity, or type 1 diabetes, which involves autoimmune reactions, type 5 diabetes results from prolonged undernutrition. This deficiency typically occurs during critical developmental windows in early childhood and adolescence.

Factors contributing to the development of the condition include poor maternal nutrition, chronic food insecurity, and frequent infections. These elements can impair the development of the pancreas, leading to underdeveloped pancreatic tissue that is unable to produce sufficient insulin.

Clinically, type 5 diabetes is referred to as severe insulin-deficient diabetes (SIDD). We see characterized by elevated blood glucose levels caused by defective pancreatic beta cells. While the condition is driven by environmental nutritional deficits, some reports indicate it can be hereditary, with a 50% chance of transmission if a parent carries the associated gene.

Global Impact and Demographics

Estimates suggest that between 20 million and 25 million people worldwide are affected by type 5 diabetes. The condition most frequently affects lean, malnourished teenagers and young adults living in resource-poor settings.

The impact extends beyond those currently residing in LMICs. Refugees and migrants from resource-poor environments may remain at risk for type 5 diabetes even after they have resettled in high-income countries.

History of Recognition and Advocacy

Malnutrition-related diabetes was first described approximately 70 years ago. The World Health Organization (WHO) initially recognized it as a distinct form of the disease in 1985, but the WHO removed this designation in 1999 citing a lack of supporting evidence and follow-up studies.

The path to the current 2025 classification was driven largely by the research and advocacy of Dr. Meredith Hawkins, an endocrinologist, professor of medicine, and founding director of the Global Diabetes Institute at Albert Einstein College of Medicine. Dr. Hawkins has highlighted that the condition has historically been vastly under-diagnosed and poorly understood.

Malnutrition-related diabetes has historically been vastly under-diagnosed and poorly understood. The IDF’s recognition of it as type 5 diabetes is an important step toward raising awareness of a health problem that is so devastating to so many people.

Dr. Meredith Hawkins

Challenges in Management and Future Steps

The medical community faces significant challenges in treating patients with type 5 diabetes. Dr. Hawkins noted that doctors remain unsure of the best treatment protocols for these patients, many of whom may not survive for more than a year following their diagnosis.

To combat these challenges, the IDF is implementing several initiatives to improve global care and understanding:

• Creation of a global research registry to track cases and outcomes.
• Development of educational modules to train healthcare professionals in recognizing and managing type 5 diabetes.
• Efforts to improve the understanding of metabolic health for young adults living in under-resourced conditions.

The formal recognition of type 5 diabetes is viewed as a critical step toward advancing health equity, ensuring that those affected by poverty-driven nutritional deficits receive appropriate medical attention and research focus.