Type 2 diabetes

Diabetes mellitus type 2 (or T2D, type 2 DM, adult-onset diabetes)[13] is a metabolic disorder where high levels of blood sugar (called hyperglycemia) can happen. If it is left untreated, it can cause heart attacks, strokes, blindness and kidney failure.

Type 2 diabetes
Other namesAdult-onset diabetes;[1]
non-insulin-dependent diabetes.[1]
Blue circle for diabetes.svg
A blue circle is the universal symbol of diabetes.[2]
Pronunciation
SymptomsIncreased thirst, frequent urination, unexplained weight loss, increased hunger[3]
ComplicationsHyperosmolar hyperglycemic state, diabetic ketoacidosis, heart disease, stroke, diabetic retinopathy, kidney failure, lower-limb amputations[1][4][5][5]
Usual onsetMiddle or older age[6]
DurationLong term[6]
CausesObesity, lack of exercise, genetics[1][6]
Diagnostic methodBlood test[3]
PreventionMaintaining normal weight, exercising, healthy diet
TreatmentDietary changes, exercise, diabetes medication such as metformin and insulin, bariatric surgery[1][7][8][9][10]
Prognosis10 year shorter life expectancy[11]
Frequency392 million (2015)[12]

Cause

Usually in the body, blood sugar levels are regulated by insulin, but in type 2 diabetes it is not. Insulin is a hormone which tells the muscle and fat cells of the body to take up sugar from the blood. If there is too much sugar in the blood for a long period of time, the muscle and fat cells start to ignore insulin. As a result, sugar stays in the blood and is not taken up, leading to a high blood sugar.[14]

Type 2 diabetes mellitus (DM) is different from diabetes mellitus type 1. In T1D, the islet cells, which make insulin in the pancreas, have been destroyed by the body, and as a result there is no insulin.[15] Diabetes type 1 usually occurs in children or young adults, while diabetes type 2 usually occurs in older people. However, recently childhood obesity has led to some young adults and teenagers developing type 2 diabetes. Type 2 diabetes makes up around 90% of cases of diabetes, while type 1 diabetes and other types of diabetes make up the other 10%.[15]

Type 2 diabetes is a result of both genetics and lifestyle. People who have relatives with diabetes type 2 are at an increased risk. They may develop diabetes if they have other risk factors in their lifestyle, for example obesity, or low amount of exercise.[16][17]

Complications

Poorly managed diabetes can lead to heart attacks, strokes, blindness and kidney failure.[16]

Treatment

Type 2 diabetes can often be treated by losing weight and exercising more, as these increase the body’s sensitivity to insulin. A medicine called Metformin is often prescribed, which works by helping the fat and muscle cells of the body listen to the signal from insulin to take up sugar from the blood.[18]

Reducing carbohydrate consumption could help with managing type 2 diabetes.[19][20]

References

  1. 1.0 1.1 1.2 1.3 1.4 Diabetes. World Health Organization (14 November 2024). Retrieved 2025-03-17.
  2. Diabetes Blue Circle Symbol. diabetesbluecircle.org (17 March 2006)International Diabetes Federation.
  3. 3.0 3.1 Diagnosis of Diabetes and Prediabetes. niddk.nih.gov (June 2014)National Institute of Diabetes and Digestive and Kidney Diseases. Retrieved 10 February 2016.
  4. Hyperosmolar hyperglycemic state: a historic review of the clinical presentation, diagnosis, and treatment. Diabetes Care 37 (11) (November 2014). p. 3124–31. doi:10.2337/dc14-0984.
  5. 5.0 5.1 Diabetic ketoacidosis: diagnosis and management. African Journal of Medicine and Medical Sciences 37 (2) (June 2008). p. 99–105.
  6. 6.0 6.1 6.2 Causes of Diabetes. niddk.nih.gov (June 2014)National Institute of Diabetes and Digestive and Kidney Diseases. Retrieved 10 February 2016.
  7. Diabetes Medications as Monotherapy or Metformin-Based Combination Therapy for Type 2 Diabetes: A Systematic Review and Meta-analysis. Annals of Internal Medicine 164 (11) (June 2016). p. 740–51. doi:10.7326/M15-2650.
  8. Effect of bariatric surgery on humoral control of metabolic derangements in obese patients with type 2 diabetes mellitus: How it works. World Journal of Clinical Cases 3 (6) (June 2015). p. 504–9. doi:10.12998/wjcc.v3.i6.504.
  9. Metabolic bariatric surgery and type 2 diabetes mellitus: an endocrinologist's perspective. Journal of Biomedical Research 29 (2) (April 2015). p. 105–11. doi:10.7555/JBR.29.20140127.
  10. Oral antidiabetic agents: current role in type 2 diabetes mellitus. Drugs 65 (3) (February 2005). p. 385–411. doi:10.2165/00003495-200565030-00005.
  11. Williams textbook of endocrinology (2011). Philadelphia: Elsevier/Saunders. p. 1371–1435. ISBN 978-1-4377-0324-5.
  12. Global, regional, and national incidence, prevalence, and years lived with disability for 310 diseases and injuries, 1990–2015: a systematic analysis for the Global Burden of Disease Study 2015. Lancet 388 (10053) (October 2016). p. 1545–1602. doi:10.1016/S0140-6736(16)31678-6.
  13. MeSH Browser. meshb.nlm.nih.gov. Retrieved 2026-04-21.
  14. Hall J. 2012. Guyton and Hall's Textbook of Medical Physiology, pp. 950-951. Saunders Elsevier, Philadelphia
  15. 15.0 15.1 Basics about diabetes, CDC, https://www.cdc.gov/diabetes/consumer/learn.htm
  16. 16.0 16.1 Kumar et al 2012. Robbins and Cotran Pathological Basis of Disease, p. 1136. Saunders Elsevier, Philidelphia
  17. Weeratunga, Praveen. Per capita sugar consumption and prevalence of diabetes mellitus--global and regional associations. BMC Public Health 14 (2014-02-20). doi:10.1186/1471-2458-14-186.
  18. Ripsin CM, Kang H, Urban RJ (January 2009). "Management of blood glucose in type 2 diabetes mellitus". Am Fam Physician 79 (1): 29–36. PMID 19145963.
  19. Goldenberg, Joshua Z.. Efficacy and safety of low and very low carbohydrate diets for type 2 diabetes remission: systematic review and meta-analysis of published and unpublished randomized trial data (in en). BMJ 372 (2021-01-13). p. m4743. doi:10.1136/bmj.m4743.
  20. Type 2 Diabetes Media

    Meng, Yan. Efficacy of low carbohydrate diet for type 2 diabetes mellitus management: A systematic review and meta-analysis of randomized controlled trials. Diabetes Research and Clinical Practice 131 (September 2017). p. 124–131. doi:10.1016/j.diabres.2017.07.006.