Type 5 diabetes


Malnutrition-related diabetes mellitus , also known as Type 5 diabetes and formerly as Type J diabetes, is a type of diabetes mellitus characterized by reduced insulin production. However, in MRDM, the insulin deficiency is primarily linked to childhood malnutrition rather than autoimmune damage to the pancreatic beta cells. Unlike Type 1 diabetes, patients with Type 5 diabetes do not develop ketonuria or ketosis.

History

MRDM diabetes was first described in Jamaica in 1955. It is most commonly seen in young men in low- and middle-income countries who have a body mass index below 19. They are often mistakenly diagnosed with Type 1 diabetes, but these patients do not develop ketonuria or ketosis, despite high blood glucose levels and a need for insulin.
In 1985, the World Health Organization officially classified "malnutrition-related diabetes mellitus" as a distinct type of diabetes. However, in 1999, this category was abolished, with the WHO citing a lack of evidence that malnutrition or protein deficiency directly causes diabetes.
Nevertheless, on April 8, 2025, MRDM was reestablished and named Type 5 by a vote during the World Diabetes Congress of the International Diabetes Federation in Bangkok, Thailand.

Diagnosis

Diagnostic criteria for Type 5 diabetes are under development. In the spring of 2025, the International Diabetes Federation tasked a working group, which includes Meredith Hawkins, a professor of medicine at Albert [Einstein College of Medicine] in The Bronx, New York, with developing official diagnostic and therapeutic guidelines for Type 5 diabetes.

Management

As of July 2025, there are no clear guidelines for treating Type 5 diabetes.
Some evidence suggests that very small amounts of insulin combined with oral medications may be most effective. It is crucial to differentiate Type 5 diabetes from Type 1 diabetes, as administering too much insulin can quickly be fatal. The diet for patients should include significantly higher amounts of protein and fewer carbohydrates, with special attention paid to correcting micronutrient deficiencies.