Type 1 diabetes is a chronic condition in which the pancreas produces little to no insulin. The pancreas is an organ responsible for producing insulin—a hormone that helps convert glucose into energy for the body. In people with type 1 diabetes, the immune system mistakenly attacks and destroys the insulin-producing beta cells in the pancreas.

As a result, insulin production stops, and glucose begins to accumulate in the blood, leading to high blood sugar levels. Over time, elevated blood sugar can damage various organs, including the kidneys, eyes, heart, and nerves.

Type 1 diabetes is considered an autoimmune disorder. While the exact cause remains unknown, researchers believe that both genetic and environmental factors contribute to its development.

Risk Factors

The immune system is designed to protect the body from harmful bacteria, viruses, and toxins. In type 1 diabetes, the immune system mistakenly attacks healthy beta cells in the pancreas. This autoimmune response disrupts insulin production, leading to increased blood glucose levels.

Although the reasons behind this immune system attack are not fully understood, a combination of genetic predisposition and environmental triggers may increase the risk of developing the disease.

Genetic Factors

Research has identified a group of genes called the human leukocyte antigen (HLA) complex as playing a significant role in type 1 diabetes. These genes—including HLA-DQA1, HLA-DQB1, and HLA-DRB1—help the immune system differentiate between the body’s own proteins and foreign invaders.

Some variations of these genes, known as haplotypes, can alter how the immune system functions. Certain HLA haplotypes may increase the risk of the immune system attacking the beta cells in the pancreas, thereby increasing susceptibility to type 1 diabetes.

However, not everyone with HLA gene variations will develop the condition. While some variations may heighten the risk, others may actually protect against the disease.

Environmental Factors

Environmental triggers, such as viral infections, are also believed to contribute to the onset of type 1 diabetes. These infections may initiate an autoimmune response, especially when combined with genetic vulnerability.

Enterovirus has shown the strongest link, with studies indicating significantly higher rates of infection in individuals at the onset of type 1 diabetes. Other viruses linked to the disease include:

  • Rotavirus: Known for causing diarrhea and gastrointestinal distress

  • Cytomegalovirus: A virus that can stay dormant and reactivate during periods of weakened immunity

  • Epstein-Barr virus: A common virus spread through saliva

  • Mumps: A contagious virus that leads to swelling of the salivary glands

  • Rubella: A virus that causes a red skin rash

The timing of viral infections may also play a role. Infections during pregnancy or early infancy appear to double the risk of a child developing type 1 diabetes later in life.

MMR Vaccine and Type 1 Diabetes

Mumps and rubella are preventable with the MMR vaccine, which protects against measles, mumps, and rubella. This vaccine is typically administered in two doses during early childhood—first between 12 and 15 months of age, and again between 4 and 6 years old.

Is Type 1 Diabetes Hereditary?

If you have type 1 diabetes, you may wonder whether it was inherited and if you could pass it on to your children. While the condition does tend to run in families, people with no family history can also develop it.

Rather than inheriting the disease itself, individuals inherit genetic traits that may increase their risk. Simply having these genes is not enough to guarantee the condition will develop—other contributing factors must also be present.

Who Is Most at Risk?

Anyone can develop type 1 diabetes, but certain groups have a higher risk. These risk factors include:

  • Age: Although type 1 diabetes can occur at any age, it most commonly affects children, teenagers, and young adults. It remains the most common form of diabetes among children.

  • Ethnicity: In the United States, non-Hispanic white individuals are more likely to develop type 1 diabetes than African American or Hispanic/Latino individuals.

  • Geography: The condition is more prevalent in countries farther from the equator. It is less common in regions such as Asia and South America, and more frequent in places like the United States, Canada, and Europe. Despite this, diagnoses of type 1 diabetes have been rising globally in recent decades.

Can You Prevent Type 1 Diabetes?

Currently, there is no known way to prevent type 1 diabetes. While researchers continue exploring potential preventive measures, no definitive method has been discovered to stop the autoimmune attack on beta cells.

A Quick Review

Type 1 diabetes occurs when the immune system mistakenly destroys the insulin-producing beta cells in the pancreas. This prevents the body from using glucose for energy, causing blood sugar levels to rise.

Although the exact cause remains unclear, a combination of genetic susceptibility and environmental triggers is believed to contribute to the development of the condition. Other risk factors, such as age, ethnicity, and geographic location, may also influence the likelihood of developing type 1 diabetes.