What is Type 4 Diabetes? What We Know So Far

‍‍We all know type 1 and type 2 diabetes, but what is type 4 diabetes? Is it even a thing?

‍Like so-called type 3 diabetes, type 4 diabetes isn’t an official medical diagnosis, but rather a still-speculative form of insulin resistance that may be linked to the aging process, not excess weight like with type 2 diabetes or an autoimmune response like type 1 diabetes. The jury is still out on whether type 4 diabetes actually exists, but either way, one thing is for sure: your chances of developing diabetes goes up as you age. 

‍Just ask Virta member Doug J., who had just retired from 42 years as an elevator mechanic when he was diagnosed. After surviving prostate cancer, he was determined to have a healthy retirement and get his diabetes under control. With help from Virta, he says, “Now I’m living a healthy retirement doing the things that I love and having quality time with my family and especially the grandkids—things I wouldn’t have had the energy to do before. It’s like everyday is Saturday.”

‍Here’s what you need to know about type 4 diabetes.

Are there actually 4 types of diabetes?

Only gestational, type 1 and type 2 diabetes are officially recognized, but there’s evidence to suggest type 3 and type 4 diabetes might also be real. Here’s what we know.

Type 1 Diabetes

Type 1 diabetes is an autoimmune condition where the pancreas produces little to no insulin. Those diagnosed with type 1 diabetes must take insulin to keep blood sugar levels as close to normal as possible. 

Type 2 Diabetes

Type 2 diabetes is the most common form of diabetes, accounting for between 90 to 95% of cases. This condition occurs when a person has high blood sugar and high insulin levels. Typically, high insulin levels can reduce high blood sugar, but individuals with type 2 diabetes develop insulin resistance, so their bodies can’t properly regulate blood sugar.

Gestational diabetes

Gestational diabetes is a form of diabetes that can occur during pregnancy in individuals who didn’t previously have diabetes. Those with gestational diabetes can’t produce enough insulin during pregnancy.

Type 3 diabetes

While type 3 diabetes isn’t an officially recognized form of diabetes, some medical professionals call Alzheimer’s disease type 3 diabetes. This is because poorly controlled blood sugar may increase your risk of developing Alzheimer’s disease. Some experts suggest calling the progression from type 2 diabetes to Alzheimer’s disease “type 3 diabetes.”

Type 4 Diabetes

Like type 3 diabetes, type 4 diabetes isn’t a formal medical diagnosis. Instead, type 4 diabetes is a proposed term for diabetes caused by insulin resistance in older people who aren’t overweight or obese. 

In a 2015 study with mice, researchers found insulin resistance in lean (not overweight) older mice. They suggest this insulin resistance may be caused by variations in the accumulation of immune system cells. The older mice with “age-related diabetes” had unusually high levels of T-regulatory immune cells in their fat tissue. This led to higher levels of internal fat accumulation, such as around the liver.

While more research in humans is needed, the researchers suggest lean older adults may go undiagnosed with diabetes because they don’t have excess weight as a risk factor.

What causes Type 4 Diabetes?

Type 4 diabetes may be caused by the aging process, specifically the accumulation of T-regulatory immune cells in fat tissue in the body. However, more study is needed. We just don’t know for sure.

How do I know if I have Type 4 Diabetes?

Without consensus on whether type 4 diabetes actually exists, you can’t know for sure. However, while there are no agreed-upon symptoms of type 4 diabetes, you should always be on the lookout for the symptoms of type 2 diabetes. These can include:

• Increased hunger
• Weight gain
• Unexplained weight loss
• Neuropathy (numbness and tingling in the hands and feet)
• Erectile dysfunction
• Slow-healing sores
• Frequent infections, including vaginal and urinary infections
• Increased urination
• Trouble focusing
• Fatigue
• Blurred vision
• Poor sleep
• Increased thirst
• Dry mouth

See your healthcare provider for regular checkups or if you have any questions about your diabetes risk factors.

If you are concerned about insulin resistance and want to live a healthier lifestyle, Virta Health may be able to help. By making healthy lifestyle changes in a medical setting with supportive resources like 1:1 virtual coaching, you can regain control of your health and feel like yourself again. See if you’re eligible for Virta Health here.