What Really Causes Type 2 Diabetes

Contrary to popular belief, type 2 diabetes (a chronic disease) isn’t caused by eating lots of sweets. Actually, the cause is still unknown, but there are certain factors that are known to increase a person’s risk of developing this metabolic disorder. There are two main categories of risks that are associated with the development of type 2 diabetes—those that you can't change (uncontrollable), and those that you can (controllable).  The more risk factors you have, the higher your risk for developing type 2 diabetes.

Uncontrollable Risk Factors
Although these factors are out of your control, it is important to know whether you fall into any of these higher-risk categories.
  • Your age. Your risk of developing type 2 diabetes increases as you get older. Diabetes most often affects people over age 40, and people over 65 are at even higher risk. It is recommended that people aged 45 and older be tested for diabetes every three years.
  • Your family history. There is some evidence that diabetes runs in families. If your parent or sibling has type 2 diabetes, for example, your risk of developing diabetes increases.
  • Your race. Certain ethnicities—African Americans, Hispanic/Latino Americans, American Indians, Asian Americans, and Pacific Islander Americans—are at high risk for developing type 2 diabetes.
  • Your health history. Women who had gestational diabetes during pregnancy are 50% more likely to develop type 2 diabetes within 10 years. Giving birth to a baby over nine pounds also increases a woman's risk. Other illnesses and conditions that are risk factors for type 2 diabetes include pre-diabetes and any condition that affects the ability of the pancreas to produce insulin, such as pancreatitis, PCOS (polycystic ovarian syndrome), high blood pressure, unhealthy cholesterol levels, metabolic syndrome, impaired glucose tolerance (IGT), and vascular disease (such as heart attack or stroke).
You may fall into many of the above categories, or none of them. In either case, pay close attention to the controllable risk factors below, as there are several lifestyle habits that you CAN change to help reduce your chance of developing type 2 diabetes.

Controllable Risk Factors
Factors within your control are related to your lifestyle—the choices you make each day about what to eat and whether or not to exercise. Even if you have a high risk for diabetes, you can take control of these factors to reduce your risk.
  • Your weight. More than 80% of people with type 2 diabetes are overweight or obese. Carrying excess weight around your abdomen and waistline (known as the "apple" shape), greatly increases your risk of diabetes. While you can't change where your body stores fat (that's genetic), you can lose weight, no matter what your body shape. Calculate your waist-to-hip ratio to find out more about your body shape and how to improve it. You can decrease your risk with each pound you lose. In fact, dropping just 10% of your body weight (25 pounds for someone who weighs 250 pounds) can have major benefits. Use your free SparkPeople nutrition plan to reach your weight-loss goals.
  • Your activity level. Physically inactive people are more likely to develop type 2 diabetes. If you don't exercise consistently, or if you take part in planned exercises fewer than three times per week, you could be at risk. To get started, read exercising with diabetes.
  • Your medications. Several types of medications, including antidepressants and antipsychotic drugs, can dramatically increase your risk. If you are already at high-risk for developing diabetes, talk to your doctor about finding an alternative medication for your condition that doesn't have this negative side effect.
  • Your diet. Though the types of food you eat do not actually cause diabetes, what you choose to eat is directly related to your health and  your weight. If your diet is high in calories and unhealthy foods (sugar, saturated fat, cholesterol, trans fats), your diet could be contributing to your diabetes risk. Use the Nutrition Resource Center as a guide for healthy eating habits.
  • Your drinking habits. Heavy alcohol use can permanently damage the pancreas and impair its ability to secrete insulin, which can result in type 2 diabetes. Limit alcohol consumption to no more than one drink daily for women or two drinks daily for men.
  • Your smoking habits. Smokers are 50% to 90% more likely to develop diabetes than nonsmokers. Smoking can harm the pancreas, increase blood sugar levels, impair your body's ability to use insulin, and cause a host of other health problems. If you smoke, taking steps to quit today can reduce your risk of serious health problems, including type 2 diabetes.
The good thing is that you can work on changing the risk factors that you can control. Studies show that maintaining a healthy weight and regularly engaging in physical activity can reduce the risk of type 2 diabetes nearly 60 percent. You should work closely with your doctor to develop a diabetes risk-reduction plan that is safe and effective for you.
For more specific information or help, talk to your health care provider. The American Diabetes Association's National Call Center also offers live advice from 8:30 a.m. to 8 p.m. EST, Monday through Friday at 1-800-DIABETES or 1-800-342-2383.

This article has been reviewed and approved by Amy Poetker, Registered Dietitian and Certified Diabetes Educator.