Because the cause of each type of diabetes is different, the risk factors vary. Forms of diabetes include:

• Type 1 diabetes. The pancreas can no longer produce insulin, resulting in high glucose in the blood and no fuel for the body.
  
  
• Type 2 diabetes. The body cannot properly use insulin to convert glucose into fuel. Insulin resistance and prediabetes typically develop before type 2 diabetes.
  
  
• Gestational diabetes. This type develops during pregnancy and generally resolves itself after delivery. The cause is not completely understood but is linked to genetics, being overweight or obese and hormonal changes. Women who develop gestational diabetes have a 40 percent greater risk of developing type 2 diabetes later in life.
  
  
• Latent autoimmune diabetes of adulthood (LADA). A variation of type 1 diabetes that has some characteristics of type 2 diabetes and is closely linked to genetic causes.
  
  
• Secondary diabetes. Diabetes caused by another condition, such as pancreatitis, or a medical treatment, such as pancreatectomy or corticosteroids.
  
  
• Double diabetes. A condition in which people with type 1 diabetes develop insulin resistance, a hallmark of type 2 diabetes, typically because of excess weight, physical inactivity and unhealthy eating habits.
  
  
• Maturity-onset diabetes of the young (MODY). A rare type of diabetes that is caused by genetic mutations.
  
  
• Wolfram syndrome. A rare genetic disorder that includes insulin-dependent diabetes, hearing problems, vision problems and diabetes insipidus.

Risk factors can generally be divided into two categories:

• Uncontrollable factors. Traits with which a person is born and cannot be changed. Uncontrollable risk factors closely linked to diabetes include:
  
  
• • Age. Type 1 usually occurs before the age of 30, whereas type 2 often occurs after age 45. MODY is also closely tied to age, with most cases developing before age 25.
    
    
  • Family history. A family history of diabetes is one of the strongest links to developing the disease. If a mother or father has diabetes, there is a greater chance their child will develop diabetes than a child whose parents do not have diabetes. The risk for diabetes also increases if a brother or sister has diabetes. Family history influences risk of all forms of diabetes but appears to be stronger in some types than others. For example, people with MODY, LADA or Wolfram syndrome inherit genetic abnormalities for these conditions.  Researchers are refining genetic tests to help predict diabetes in families with a history of the disease.
    
    
  • Race. Certain races are more prone to developing a specific type of diabetes, especially type 1 and type 2. It is believed that diabetes may be caused by inherited traits with a race or ethnic group, as well as lifestyles that are common with that race.
    
    
  • Sex. Though males make up slightly less than half the U.S. population, they account for 53 percent of the adult cases of diabetes, according to the National Institutes of Health (NIH). The prevalence of diabetes in men and women was similar until 1999, when a growing disparity began, according to the U.S. Centers for Disease Control and Prevention (CDC). An estimated 10.5 percent of American men and 8.8 percent of American women had diabetes in 2005. Research to account for the discrepancy is lacking.
    
    
• Controllable factors. Risk factors that can be changed by an individual. Some risk factors that can be reduced include:
  
  
• • Weight. Excess weight is a major risk factor for type 2 diabetes, double diabetes and gestational diabetes. Recent research indicates obesity can also cause earlier onset of type 1 diabetes in some cases. Extra pounds can cause metabolic problems, including high blood pressure and unhealthy cholesterol levels. Obese individuals also tend to develop Insulin resistance. All of these factors can increase a person’s risk of developing type 2 diabetes.
    
    
  • Lifestyle. Low activity levels and poor exercise habits place a person at high risk for diabetes, particularly type 2 and double diabetes. Stress can also contribute. Keeping active helps reduce weight, cholesterol, blood pressure and stress, which in turn lowers the risk for developing diabetes or its complications.
    
    
  • Smoking and alcohol. By not smoking and limiting the use of alcohol, individuals can reduce their risk of developing type 2 diabetes. In other types of diabetes, avoiding these elements can help prevent further medical complications.

Sources of secondary diabetes are sometimes controllable but sometimes not. For example, pancreatitis is often due to alcohol abuse but can also be due to genetics or other causes. Diabetes caused by medication, which often resolves after the drug is discontinued, may be preventable if another treatment is available but may be unavoidable if the drug is essential.

The uncontrollable and controllable traits for diabetes can be related to one another. For example, a child who is born into a family of people who have diabetes and who has poor eating and exercise habits is likely to develop those habits as well. The combination of a history of diabetes and an unhealthy lifestyle places that child at a higher risk for developing diabetes.

Diabetes is on the rise in the United States and worldwide, especially for people of certain ages and ethnic groups. Although it is impossible to change certain factors, individuals can reduce their risk by maintaining a healthy, active lifestyle.