Diabetes types can be confusing. So, let’s talk about the two major types of diabetes.

Type 2 diabetes

Type 2 diabetes is a slowly progressing chronic condition. Before diagnosis, a person living with type 2 diabetes develops insulin resistance. Insulin resistance is when the pancreas produces insulin; however, the insulin does not work properly. Remember that insulin is the ‘key’ that ‘unlocks’ cell ‘doors’ and allows glucose to flow in and be used as energy. Insulin is like soldiers in an army – your army. When an army encounters a difficult barrier, extra soldiers are called in to assist. That is, the pancreas produces extra insulin to get glucose into your insulin-resistant cells. Unfortunately, an army only has so many soldiers. As a result, your pancreas has only so much ability to produce insulin and, with the extra load, becomes tired and will produce less insulin.

With type 2 diabetes, over time, less insulin is produced, and your cells remain resistant to insulin. A healthy lifestyle and most medications will reduce the need for insulin production and improve insulin resistance. Type 2 diabetes is progressive so at some point, if you live long enough with type 2 diabetes, supplementing insulin by injection is necessary; however, your body is still producing insulin.

Type 1 diabetes

Type 1 diabetes is an autoimmune condition. A virus, physical or chemical stressor triggers the immune system to stop recognising its body cells. In the case of type 1 diabetes, these are the cells (beta cells in the pancreas) that produce insulin. When your immune system does not recognise a cell or group of cells, it destroys them. Once about 90% of the beta cells are destroyed, the amount of insulin produced is not enough to use glucose as energy. In a younger person  type 1 diabetes develops very quickly, happening in a few days. However, as our immune system ages with us, the destruction of beta cells is slower. With an older person who develops type 1 diabetes, the progression of rising glucose levels and dropping insulin production with the destruction of beta cells may look like type 2 diabetes. To add to the confusion, the person may also have some insulin resistance. In type 1 diabetes, insulin injections are required to replace what the body is not making.

In summary

Type 2 diabetes does not progress to type 1 diabetes as they are two different conditions. Treatment for type 2 diabetes may go from diet and exercise to oral medications to non-insulin injectables and eventually to insulin injections over time. Type 1 diabetes which starts in an older person may be mistaken for type 2 diabetes before the correct diagnosis is made. We recognise that people may have diabetes that doesn’t fit either category. For example, a person may have damaged their pancreas, have insufficient beta cells from birth, or have genetic conditions that stop the cells from recognising insulin well. See the table below for a summary of the differences.

By Donna Itzstein, Pharmacist, Credentialled Diabetes Educator