Type 1 vs Type 2 Diabetes
When I see a patient who has been newly diagnosed with diabetes, one of the first questions I ask them is, “What type of diabetes do you have?”
Often, when they walk into my office, they aren’t sure. Or they have a misconception about the types of diabetes. For example, if they required insulin immediately at the onset of diagnosis, they assumed right away that they have type 1 diabetes, when they actually had type 2 diabetes.
So let’s clear up some of those misconceptions today, and explain the differences between type 1 diabetes and type 2 diabetes.
How Are Type 1 Diabetes and Type 2 Diabetes Alike?
Both type 1 diabetes and type 2 diabetes can occur at any age. In the past, we had incorrectly assumed that type 1 diabetes was “juvenile-onset” and that type 2 diabetes was “adult-onset.” However, we now know that type 1 diabetes is an autoimmune disease, meaning that it can occur at any age. Type 2 diabetes does occur more often in adults, but it is occurring at an alarming rate in children.
In the past, type 1 diabetes was called “insulin-dependent” diabetes and type 2 diabetes was previously called “non-insulin-dependent” diabetes.
Both types of diabetes may require insulin – people with type 1 diabetes will always require insulin (which we will discuss in greater detail), while people with type 2 diabetes will sometimes require insulin – meaning both types of diabetes are “insulin-requiring” diabetes.
Both types of diabetes require proper management of blood sugar levels, either through the use of insulin (as discussed above) or through other means (oral or injectable medications and diet and exercise, for people with type 2 diabetes). If blood sugar levels are not properly controlled, the risk of complications increases.
Complications include kidney failure, diabetic retinopathy – which can lead to blindness, heart disease, stroke, diabetic neuropathy, and amputations.
The Type 1 and Type 2 Diabetes Difference
Although there are a lot of similarities, there are also stark differences in type 1 and type 2 diabetes.
For starters, type 1 diabetes is an autoimmune disease. In general, our bodies have an immune system that protects us from illness by attacking foreign bodies. However, if you have an autoimmune disease, it can’t always tell from the “good things” from the “bad things” so the body essentially begins to attack itself.
In the case of type 1 diabetes, the pancreas is attacked, and the beta cells (which produce insulin) are destroyed. And type 1 diabetes is one of about 80 types of autoimmune diseases!
This all boils down to the fact that the fact that you can’t prevent type 1 diabetes.
Type 2 diabetes is a metabolic disease as opposed to an autoimmune condition. Generally, insulin secretion from the beta cells of the pancreas is inadequate because the body has developed a condition called insulin resistance.
According to Merck Manual, “Pathogenesis is complex and incompletely understood. Hyperglycemia develops when insulin secretion can no longer compensate for insulin resistance. Although insulin resistance is characteristic in people with type 2 DM and those at risk of it, evidence also exists for beta-cell dysfunction and impaired insulin secretion.”
To put this very simply, we don’t know exactly the pathophysiology of type 2 diabetes, but hyperglycemia (high blood sugar) develops due to insulin resistance.
What Causes Diabetes?
As we’ve already discussed, type 1 diabetes is an autoimmune disease. Thus, there is no known cause of type 1 diabetes, as there is often no known cause of other autoimmune diseases. We do know that there has to be a catalyst to “turn on” the autoimmune response. Genetics seem to play a role for some people, as well as environmental factors.
For example, a virus may trigger this response. There are ongoing research studies, such as TrialNet, that are attempting to pinpoint causes of type 1 diabetes.
There are several factors that seem to cause type 2 diabetes. Having one of these factors may not cause it, but having several may increase the risk:
- Genes/family history – certain ethnicities are known to have a higher predisposition to getting type 2 diabetes. For example, African Americans and American Indians are much more likely to get type 2 diabetes than Caucasians. Genetics can also predispose to obesity, which also can contribute.
- Obesity/overweight – the likelihood of developing type 2 diabetes increases with weight gain. The location of the excess weight can also make a difference. Excess belly fat is linked not just to type 2 diabetes, but insulin resistance and heart and vascular disease as well.
- Insulin resistance – the precursor to type 2 diabetes, insulin resistance is when the cells of the body (specifically the muscle, fat, and liver cells) do not use insulin efficiently. This means that more insulin must be produced for glucose to enter the cells. Eventually, the pancreas is unable to keep up with the excess insulin production, causing blood sugar levels to rise.
Next page: the symptoms of type 1 and type 2 diabetes, and more.