What are the Types of Diabetes?
There are multiple types of diabetes. Diabetes mellitus isn’t one single disease but instead is a group of diseases related to blood glucose, or blood sugar, levels that are too high. Elevated blood glucose is known as hyperglycemia, and it can have a harmful effect on overall health. Understanding the different types of diabetes will help you know if you are at risk.
Types of Diabetes and What They Are
There are three primary types of diabetes as well as a few rare secondary types of the illness. In all types of diabetes, the body can’t metabolize into energy the blood glucose created during the digestion of carbohydrates.
The reason for this is that in diabetes, the body either has no insulin or doesn’t use insulin efficiently. The result is that the glucose can’t enter the body’s cells and instead accumulates in the bloodstream.
The different types of diabetes relate to the source of the problem—insulin—and why it goes awry.
- Type 1 diabetes (T1) and latent autoimmune diabetes of the adult (LADA)
Formerly called juvenile onset diabetes or insulin dependent diabetes mellitus, T1 occurs when the immune system attacks the beta cells in the organ called the pancreas. The beta cells produce insulin, so when the pancreas is attacked, it can no longer make insulin. People with T1 must take insulin daily, usually multiple times a day, because they don’t have any of their own.
T1 usually develops in childhood or adolescence; half of all cases of T1 are diagnosed by the early teen years. Most other cases are diagnosed by the twenties. That said, there is a type of T1 diabetes called latent autoimmune diabetes of the adult (LADA). LADA develops gradually over the course of years, and insulin is often not needed until adulthood.
- Type 2 diabetes (T2)
Formerly referred to as insulin resistant diabetes, T2 isn’t an autoimmune disorder like T1. The pancreas does make insulin. The problem in T2 diabetes is that the pancreas either produces too little insulin or it produces enough insulin, but the body doesn’t use it well.
Type 2 diabetes typically occurs in overweight adults over the age of 40; however, it can sometimes occur in people who are not overweight. Also, the number of children diagnosed with T2 is on the rise thanks to the increasing rates of childhood obesity.
- Gestational Diabetes (GDM)
Gestational diabetes mellitus, or GDM, is a type of diabetes that occurs only during pregnancy. During pregnancy, hormones in the placenta make it difficult for the mother’s body to absorb glucose. This is a normal part of pregnancy, and in most cases the mother’s pancreas compensates by making extra insulin. For reasons largely unknown, in rare cases the mother’s body can’t make enough insulin to compensate for the new hormones. The result is gestational diabetes. GDM disappears within about six weeks of delivery.
- Other (Secondary) Types of Diabetes
While T1, T2, and gestational diabetes are the three main types of diabetes, there are some rare cases in which someone can develop hyperglycemia. These are considered secondary diabetes because they develop due to another medical condition that affects the pancreas.
Secondary types of diabetes can arise from
- Hormonal problems (one example is Cushing’s syndrome)
- Genetic syndromes
- Certain illnesses
Despite the fact that there are rare cases in which secondary diabetes develops, the answer to the question,How many types of diabetes are there? is three: type 1, type 2, and gestational diabetes.
Types of Diabetes by the Numbers
According to The Health Reference Series: Diabetes (Judd, 2011), type 2 diabetes is by far the most common form of diabetes. The statists for the various types of diabetes:
- T1 comprises 5-10 percent of all cases of diabetes
- T2 makes up 90-95 percent of diabetes diagnoses
- GDM occurs in 4 to 7 percent of pregnancies and is not included in overall diabetes statistics as it is not a permanent condition
- Rare, secondary, types of diabetes make up 1-2 percent of diabetes cases
Types of Diabetes: Mellitus vs. Insipidus
Types 1 and 2 and GDM are forms of diabetes mellitus. There is another disease called diabetes insipidus.
Diabetes mellitus and diabetes insipidus are two completely different illnesses. People easily confuse the terms because of their shared word “diabetes.”
The word “diabetes” comes from Greek and refers to excessive urination. This is a symptom of all types of diabetes mellitus and diabetes insipidus. It’s the only similarity between the two diseases. Beyond this, they are unrelated.
Diabetes insipidus is a kidney disease. Diabetes mellitus is a metabolic, and in the case of T1 autoimmune, disease. When people use the lone term “diabetes,” they are referring to diabetes mellitus. All types of diabetes mellitus involve hyperglycemia and subsequent health problems, each in its own way.
Last Updated: 09 January 2019
Reviewed by Harry Croft, MD