Type 2 diabetes is a serious condition, and it’s becoming more common: As of 2012, 90% of the more than 29 million Americans with diabetes had type 2 diabetes. An additional 86 million had prediabetes, a precursor to type 2. Although no one knows specifically what causes type 2 diabetes or why some people and not others develop diabetes, experts do know that having certain risk factors will increase your odds of having the disease.

Primary Risk Factor: Obesity

Obesity is the primary risk factor for developing type 2 diabetes, especially if you carry excess weight around your abdomen. That’s because the more fat you have, the more resistant your cells become to insulin, the hormone needed to metabolize carbohydrates and manage blood sugar levels. If you’re insulin resistant, blood sugar cannot get into your cells, where it is converted to energy.

However, patients in the early stages of type 2 diabetes who lose weight can actually help reverse the effects of insulin resistance, according to Amber Taylor, MD, Director of The Diabetes Center at Mercy, a division of The Center for Endocrinology at Mercy Medical Center in Baltimore.

Other Risk Factors

Numerous other factors can also increase your risk of developing diabetes. The more of these factors you have, the higher your risk. The most important risk factors include:

  • Hypertension, or blood pressure of 140/90 or higher.
  • Elevated blood sugar, or a prior diagnosis of prediabetes. Prediabetes is a condition in which blood sugar (glucose) levels are higher than normal, but not high enough to be classified as diabetes. Upon blood testing, you may be told you have impaired fasting glucose (IFG) or impaired glucose tolerance (IGT).
  • High blood triglyceride (fat) levels. Triglycerides above 250 mg/dl (milligrams per deciliter of blood) raise your risk of diabetes.
  • Low levels of protective HDL (high-density lipoprotein) cholesterol. HDL levels below 35 mg. increase your risk.
  • A history of gestational diabetes. If you’re a woman who had gestational (pregnancy-related) diabetes or you gave birth to a baby weighing more than 9 pounds, your risk of diabetes is higher.
  • A history of polycystic ovary syndrome (PCOS). If you’ve ben diagnosed with polycystic ovary syndrome, you have an increased risk.
  • A family history of diabetes. Having a parent, brother, or sister with diabetes increases your own chances of developing the disease.
  • Advancing age. Your risk increases after age 45, although there has been a significant increase in type 2 diabetes diagnoses in children, teens, and young adults.
  • Sedentary lifestyle. Lack of physical activity is a primary factor in overweight/obesity and the development of diabetes and other chronic diseases. Exercise uses sugar for energy, helps you control your weight, and decreases insulin resistance, allowing for better uptake of sugar from the bloodstream.
  • Race and Ethnicity. Type 2 diabetes is more prevalent among African Americans, Native Americans, Hispanic Americans, Asian Americans, and Pacific Islanders, though the reasons are not understood.

Early Warning Signs

According to The American Diabetes Association, many people with type 2 diabetes go undiagnosed and miss out on the benefits of early treatment because they misinterpret warning signs. If you consistently have any of the symptoms listed below, regardless of how mild, see your health care provider:

  • Frequent urination
  • Frequent thirst
  • Feeling hungry even though you are eating normally
  • Fatigue
  • Blurred vision
  • Slow-healing wounds
  • Tingling, pain or numbness in your hands and/or feet

"If you have type 2 diabetes, you should be seen every three months by your health care provider," says Taylor. "We typically do a blood test to check the Hba1c (glycated hemoglobin), a marker of long-term blood sugar control, every three months, and all other blood tests once a year." The Hba1c test, which measures a patient’s average blood sugar level over the past month or so, is also used to diagnose diabetes.

If necessary, your physician can help you form a care team whose members may include an endocrinologist (a doctor who specializes in hormones), a dietitian, diabetes educator, an ophthalmologist (eye doctor), and other medical and health specialists. Your team can help you manage the condition and slow down or prevent its progression.

Amber Taylor, MD, reviewed this article.


American Diabetes Association. "Statistics About Diabetes." Accessed August 11, 2014.

Joslin Diabetes Center. "Type 2 Diabetes: Know Your Risk Factors." Accessed June 4, 2014. 

Narayan KMV, Boyle JP, Thompson TJ, Sorensen SW, Williamson DF. "Lifetime Risk for Diabetes Mellitus in the United States." JAMA Oct 8, 2003:290(14). Accessed June 4, 2014 

"All About Insulin Resistance." American Diabetes Association.