Preventing type 1 diabetes
Currently there is no way to prevent type 1 diabetes; however, ongoing studies are exploring ways to prevent diabetes in those who are most likely to develop it. People who have a parent, brother, or sister with type 1 diabetes and are willing to participate in one of these studies should talk with their health professional. They may want to be tested for islet cell antibodies, because the presence of these antibodies increases the risk of developing diabetes.

Previous studies in animals and a small trial in humans found that low doses of oral or injected insulin could prevent type 1 diabetes. However, a large study has found that small doses of injected insulin do not prevent or delay type 1 diabetes. A study of whether oral insulin can prevent or delay type 1 diabetes is ongoing.

Another study found that supplementing infants' diets with vitamin D reduced the risk for type 1 diabetes. However, too much vitamin D can be harmful. A child should not be given extra vitamin D unless he or she has a deficiency of the vitamin.

Vaccines have not been found to contribute to the development of type 1 diabetes. Children who are at risk for developing diabetes still need to get the recommended immunizations. See the childhood immunizations schedule recommended by the U.S. Advisory Committee on Immunization Practices, the American Academy of Pediatrics, and the American Academy of Family Physicians.

Preventing diabetes complications
People with type 1 diabetes can help prevent or delay the development of complications such as eye, kidney, heart, blood vessel, and nerve diseases by keeping their blood sugar near normal levels. They also need regular medical checkups to detect early signs of complications. If complications are treated early, the damage may be stopped, slowed, or possibly reversed.

People who have other health problems along with diabetes, such as high blood pressure or high cholesterol, need to treat those conditions. Not smoking also can reduce the risk of complications. Having other health problems can increase the risk for complications from diabetes.

Preventing flu and pneumococcal disease
People who have diabetes should have a flu shot every year and a pneumococcal vaccine every 5 years. The pneumococcal vaccine helps prevent infections caused by pneumococcal bacteria. People with diabetes, especially those who have heart or kidney disease, are at high risk for complications, hospitalization, and death from flu and pneumococcal disease.