What is Diabetes?

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Diabetes is a disease in which blood sugar (glucose) levels are above normal. High blood sugar can damage the vision, kidneys or nervous system. Type 1, type 2, and gestational diabetes are the main types of diabetes. It affects more than 400 million people worldwide and is predicted to be the seventh leading cause of death in 2040.

Diabetes explained in first person

Professionals and patients explain how you live with the disease
Without the management of the disease by the patient, it is very difficult to achieve some adequate therapeutic objectives. Therefore, a change in lifestyle will be essential.
Every cloud has a silver lining, my habits are so much healthier now.

Types of diabetes

  • Type 1 (T1D). Represents between 5% and 10% of all cases of diabetes diagnosed. It is characterised by deficient insulin production and must always be treated by administering insulin.
  • Type 2 (T2D). Represents 80–90% of all cases. It is characterised by the fact that the body does not use its own insulin correctly and is very strongly associated with being overweight and a sedentary lifestyle.
  • Gestational. This is identified by an increase in sugar levels (hyperglycaemia) that arises during pregnancy.
  • Monogenic. This type represents 1–2% of all cases. The main subtype of monogenic diabetes is MODY diabetes (Maturity-Onset Diabetes of the Young).
  • Drug-related diabetes. The medicines most typically associated with diabetes are corticosteroids and immunosuppressants. 
  • Diabetes due to partial or total removal of the pancreas.

Diabetes in numbers in the world

Diabetes affects millions of people around the world. Type 2 diabetes is associated with a rapid increase in weight, obesity and physical inactivity. A total of 415 million people worldwide have diabetes. Diabetes is expected to become the seventh largest global cause of death by 2040 (www.diabetesatlas.org 7th Edition 2015).

Diabetes in numbers in Spain

According to the study Di@bet.es, 13.8% of the Spanish population aged over 18 have type 2 diabetes which equates to over 5.3 million people. Of this group, almost 3 million have been diagnosed, while a further 2.3 million are unaware they have the disease. Delays in diagnosing diabetes mean that half of all patients have already developed a complication, because it can affect other organs such as the kidneys, eyes, heart or the nervous system, when it is finally detected. 

There are estimated to be around 600,000 people with diabetes in Catalonia. According to the 2015 Health Survey of Catalonia (ESCA), diabetes affects 8.4% of the population aged over 15 years. The incidence increases with age in both sexes.

Substantiated information by:

Daría Roca Espino
Enrique Esmatjes Mompo
Irene Vinagre Torres
Margarida Jansà Morató
Mercè Vidal Flor

Published: 20 February 2018
Updated: 24 November 2021

The donations that can be done through this webpage are exclusively for the benefit of Hospital Clínic of Barcelona through Fundació Clínic per a la Recerca Biomèdica and not for BBVA Foundation, entity that collaborates with the project of PortalClínic.


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