Diabetes happens when the body does not have enough insulin to move glucose from the blood to the cells. This causes it to build up in the blood instead of being used by the cells for energy. Type 2 is more common in adults.
Type 1 diabetes happen when the body does not make insulin (this usually happens at a young age, but not always.)
Type 2 happens when the body becomes resistant to insulin or when the pancreas cannot make enough. This may be due to a person’s genes and habits.
Type 2 is more common in people with obesity and those over 45 years of age. People who are American Indian, Alaska natives, Afro American, and Hispanic are at higher risk. Some other common risks are:
- Prediabetes—formerly known as “borderline diabetes”
- Metabolic syndrome—fat around the belly and high cholesterol, high glucose, and blood pressure
- Polycystic ovary syndrome
- Past gestational diabetesor having a baby that weighs over 9 pounds at birth
- Poor eating habits
- Lack of exercise
- High blood pressure
- Taking certain medicines, such as glucocorticoids or thiazides
Most people do not have problems right away. Others may have:
- Excessive urination
- Excessive thirst
- Blurry eyesight
- Weight loss
- Being very tired
- Frequent infections (especially urinary tract and vaginal yeast infections)
The provider will ask about your symptoms and health history. A physical exam will be done.
Diabetes is diagnosed with blood tests that check for high glucose levels. More than one test may be done.
These blood tests will also be done to find out whether it is type 1 or type 2:
- Insulin level or C-peptide tests to see how much insulin is being made by the pancreas
- Tests that look for antibodies that are working against the pancreas
The goal is to keep glucose levels at close to target levels. This can be done with:
Healthy habits can help manage type 2, such as:
- Testing blood glucose levels as needed or recommended
- Working with a dietitian to make a meal plan that will help keep blood glucose levels normal
- Getting enough exercise
- Reaching a healthy weight
Most people may need medicine to control blood glucose. Metformin is a common oral medication that is given as a first step.
There are many options including oral and injectable medications for treating diabetes if the initial treatment choice is inadequate. This may include insulin which may be given by injection, inhalation or pump.
Although it may not be possible to prevent the onset of diabetes, following healthy habits such as exercising, staying at a healthy weight, and eating right will lower the risk of developing diabetes.
American Diabetes Association: http://www.diabetes.org
National Diabetes Information Clearinghouse: http://diabetes.niddk.nih.gov
Canadian Diabetes Association: http://www.diabetes.ca
Public Health Agency of Canada: http://www.phac-aspc.gc.ca
American Association of Clinical Endocrinologists, American College of Endocrinology. Comprehensive Type 2 Diabetes Management Algorithm 2017. Endocr Pract. 2017 Feb;23(2):207-238.
American Diabetes Association Classification and Diagnosis of Diabetes of Diabetes Mellitus. Diabetes Care. 2015 Jan;38 Suppl:S8-S16.
American Diabetes Association. Standards of medical care in diabetes. Diabetes Care. 2019 Jan; 42 (Suppl 1):S1-S193,
Diabetes mellitus type 2 in adults. EBSCO DynaMed website. Available at: https://www.dynamed.com/condition/diabetes-mellitus-type-2-in-adults . Updated February 14, 2019. Accessed November 1, 2019.
Diabetes mellitus type 2 in children and adolescents. EBSCO DynaMed website. Available at: https://www.dynamed.com/condition/diabetes-mellitus-type-2-in-children-and-adolescents . Updated May 7, 2019. Accessed November 1, 2019.
Dietary considerations for patients with type 2 diabetes. EBSCO DynaMed website. Available at: https://www.dynamed.com/management/dietary-considerations-for-patients-with-type-2-diabetes . Updated March 11, 2019. Accessed November 1, 2019.
Symptoms & Causes of Diabetes. National Institute of Diabetes and Digestive and Kidney Diseases website. Available at: https://www.niddk.nih.gov/health-information/diabetes/overview/symptoms-causes. Updated December 2016. Accessed November 1, 2019.
9/16/2014 DynaMed Plus Systematic Literature Surveillance https://www.dynamed.com/prevention/diabetes-mellitus-type-2-prevention : Zhou D, Yu H, He F, et al. Nut consumption in relation to cardiovascular disease risk and type 2 diabetes: a systematic review and meta-analysis of prospective studies. Am J Clin Nutr. 2014;100(1):270-277.
12/14/2016 DynaMed Plus Systematic Literature Surveillance https://www.dynamed.com/condition/risk-factors-for-diabetes-mellitus-type-2 : Shen HN, Yang CC, Chang YH, Lu CL, Li CY. Risk of diabetes mellitus after first-attack acute pancreatitis: a national population-based study. Am J Gastroenterol. 2015;110(12):1698-1706.
10/1/2018 DynaMed Plus Systematic Literature Surveillance https://www.dynamed.com/condition/risk-factors-for-diabetes-mellitus-type-2 : Mantovani A, Byrne CD, Bonora E, Targher G. Nonalcoholic fatty liver disease and risk of incident type 2 diabetes: a meta-analysis. Diabetes Care. 2018;41(2):372-382.
EBSCO Medical Review Board Daniel A. Ostrovsky, MD