The hidden diabetes type you may not have heard of: Type 1.5

When most people think of diabetes, they picture two categories: type 1 and type 2. But doctors say there’s another form that doesn’t get nearly as much attention.It’s called latent autoimmune diabetes in adults (LADA), sometimes nicknamed “type 1.5 diabetes.” Often confused with type 2, this slow-burning autoimmune disease can leave patients misdiagnosed for years, putting them at risk of serious complications if not caught early.All three types—type 1, type 2, and LADA—fall under the umbrella of diabetes mellitus, a condition marked by elevated blood sugar. While type-1 occurs when the pancreas doesn’t make enough insulin, type-2 diabetes develops when the body stops responding properly to insulin—often due to weight, inactivity, or other lifestyle factors.LADA, however, straddles the two. Like type 1, it is autoimmune in nature, but unlike the rapid onset of childhood diabetes, it develops slowly in adults, typically after age 30. According to a study, genetic factors are involved, but environmental triggers like respiratory infections may also play a role. The American Diabetes Association estimates that LADA makes up 2 to 12 percent of diabetes cases in adults.Because its symptoms mimic both type 1 and type 2—thirst, excessive urination, weight loss, and infections—LADA is easy to miss. Experts believe that about 5 to 10 percent of LADA cases are misdiagnosed, often because doctors assume autoimmune diabetes only occurs in children. The result? Patients follow type 2 treatment plans, diet changes, exercise, oral medications—but their blood sugar keeps rising.This delay can be dangerous. Dr. Kathleen Dungan of The Ohio State University Wexner Medical Center explains to the National Geographic that people with LADA need insulin “sooner than people with type 2 diabetes.” If left untreated, it can lead to diabetic ketoacidosis, a potentially fatal complication. Getting tested for LADA isn’t always straightforward. Many primary care doctors don’t routinely check for it, which means patients often need to advocate for themselves.The key, according to Dr. Kathleen Wyne, also of The Ohio State University Wexner Medical Center, is antibody testing: “The important thing is to have them draw the five antibodies—GAD, ICA, IAA, IA2, and ZnT8. Just measuring glucose, or A1c, or c-peptide—or any combination of those three—is not adequate.”Once diagnosed, treatment can be very effective. Insulin therapy is the cornerstone, and many patients use insulin pens or pumps combined with continuous glucose monitors. In some cases, newer drugs like GLP-1 agonists (Ozempic, Wegovy) may also help.