Diabetes is a chronic disease that occurs either when the pancreas does not produce enough insulin or when the body cannot effectively use the insulin it produces. Insulin is a hormone that regulates blood glucose. Hyperglycaemia, also called raised blood glucose or raised blood sugar, is a common effect of uncontrolled diabetes and over time leads to serious damage to many of the body's systems, especially the nerves and blood vessels.[1]
The three main types are type 1 diabetes, type 2 diabetes and gestational diabetes. More than 95% of people with diabetes have type 2 diabetes.[1,2]
Global Impact
Diabetes is one of the major noncommunicable diseases worldwide. According to WHO, approximately 830 million people were living with diabetes in 2022, compared with 200 million in 1990. About 14% of adults aged 18 years and older were living with diabetes in 2022.[1]
Diabetes was directly responsible for approximately 1.6 million deaths in 2021, while kidney disease caused by diabetes accounted for an additional 530,000 deaths. High blood glucose also contributes substantially to cardiovascular mortality.[1]
Impact in India
India has one of the largest populations of people living with diabetes worldwide. According to the IDF Diabetes Atlas, approximately 90 million adults aged 20–79 years in India were living with diabetes in 2024, with an age-standardized prevalence of approximately 10.5%.[3]
The number of adults with diabetes in India is projected to rise substantially in the coming decades, highlighting the need for stronger prevention, early detection and long-term management.[3]
The ICMR-INDIAB national study (ICMR-INDIAB-24) reported a weighted national prevalence of gestational diabetes mellitus (GDM) of 22.4%, indicating that nearly one in four pregnant women in India were affected. The prevalence was 19.2% in early pregnancy (<20 weeks) and 23.4% in later pregnancy (≥20 weeks).[4]
According to the Chandigarh NCD Registry (July 2018–December 2021), 54 cases of young-onset diabetes were recorded in Chandigarh, of which 81.5% were Type 1 diabetes. Among these young-onset diabetes cases, 77.8% were aged 18 years or younger.[5]
Types of Diabetes
Type 1 Diabetes: An autoimmune condition in which the body's immune system destroys the insulin-producing cells of the pancreas. People with type 1 diabetes require daily insulin treatment to survive.[2]
Type 2 Diabetes: Occurs when the body does not use insulin effectively and gradually becomes unable to produce sufficient insulin. It is associated with genetic factors, ageing, excess body weight and physical inactivity.[1,2]
Gestational Diabetes: Develops during pregnancy and increases the risk of complications during pregnancy and delivery. Women who experience gestational diabetes and their children also have an increased risk of developing type 2 diabetes later in life.[1]
Risk Factors
Important risk factors for type 2 diabetes include overweight and obesity, physical inactivity, unhealthy diet, increasing age, family history of diabetes, previous gestational diabetes and tobacco use.[1,2]
Signs and Symptoms
Symptoms of diabetes may include:
- Increased thirst
- Frequent urination
- Unexplained weight loss
- Fatigue
- Blurred vision.[1]
Symptoms of type 2 diabetes may be mild and develop gradually over several years. Consequently, some people may remain undiagnosed until complications develop.[1]
Complications
Long-term uncontrolled diabetes can cause serious complications, including:
- Heart attack and stroke
- Kidney disease and kidney failure
- Diabetic retinopathy and vision loss
- Nerve damage
- Foot ulcers and infections
- Lower-limb amputation.[1]
Prevention and Management
Type 2 diabetes can often be prevented or delayed through a healthy diet, regular physical activity, maintaining a healthy body weight and avoiding tobacco use.[1]
Diabetes management includes healthy eating, regular physical activity, blood glucose monitoring and medications when required. People with type 1 diabetes require insulin, while people with type 2 diabetes may require oral medicines, injectable medicines or insulin depending on their condition.[1,2]
Regular monitoring of blood glucose, blood pressure and cholesterol, along with screening for kidney disease, diabetic retinopathy and foot complications, is important for preventing or delaying diabetes-related complications.[1]
References
- World Health Organization. Diabetes. Geneva: World Health Organization; 2024 Nov 14. Available from: https://www.who.int/news-room/fact-sheets/detail/diabetes
- World Health Organization. Diabetes: questions and answers. Geneva: World Health Organization; 2026 Sep 1. Available from: https://www.who.int/news-room/questions-and-answers/item/diabetes
- International Diabetes Federation. IDF Diabetes Atlas. 11th ed. Brussels: International Diabetes Federation; 2025. Available from: https://diabetesatlas.org/
- X. Mohan V, Deepa M, Tandon N, Pradeepa R, Subashini R, Janeline L, et al. Prevalence of gestational diabetes mellitus in India: The ICMR-INDIAB national study (ICMR-INDIAB-24). Indian J Med Res. 2025;162(4):460–469. Available from: https://ijmr.org.in/prevalence-of-gestational-diabetes-mellitus-in-india-the-icmr-indiab-national-study-icmr-indiab-24/
- Thakur JS, Malhotra P, Bhadada SK, Kapoor R, Vijayvergiya R, Khurana D, Arora P. Chandigarh Noncommunicable Diseases (NCD) Registry, July 2018 to December 2021. Chandigarh: World NCD Federation; 2025.