Type 2 diabetes: Symptoms, causes, and what science has to say

India is home to an estimated 101 million people with diabetes and 136 million with prediabetes. Doctors say the real danger is not just high sugar but how silently it damages the body.


Type 2 diabetes is a long-term metabolic disorder that occurs when the body cannot use insulin properly or when the body gradually stops producing enough insulin. Insulin is the hormone that lets glucose from food enter the cells and turn into energy. If this system breaks down, glucose remains in the blood. Blood sugar remains high.


The scale is big. The ICMR-INDIAB study, published in The Lancet Diabetes & Endocrinology, estimated that in 2021, India had 101 million people with diabetes and 136 million with prediabetes. The Government of India also highlighted that nearly 57% of people with diabetes are projected to be undiagnosed.


The disease often begins insidiously. Common symptoms include excessive thirst, frequent urination, unusual fatigue, increased hunger, blurred vision, slow wound healing, recurrent infections, numbness or tingling in the feet and unexplained weight change. Many people dismiss these signs as stress, ageing, heat or weakness.


The main reasons are insulin resistance and a decreased function of the pancreas. Risk factors include abdominal obesity, physical inactivity, high intake of refined carbohydrates, sugary drinks, poor sleep, chronic stress, family history, hypertension, smoking and PCOS. Indians are also more susceptible because South Asians are prone to insulin resistance and diabetes at lower body weight than many Western populations.


Prevention is powerful. Research shows. The landmark U.S. Diabetes Prevention Program showed that intensive lifestyle change reduced the risk of developing Type 2 diabetes by 58 percent and metformin by 31 percent in high-risk adults.


The long-term Da Qing Diabetes Prevention Study also showed that lifestyle intervention in persons with impaired glucose tolerance delayed the onset of diabetes by almost 4 years and reduced cardiovascular events, microvascular complications, cardiovascular deaths, and all-cause deaths over 30 years .


Good control of sugar is important after diagnosis too. The UKPDS showed that intensive glucose control reduces microvascular complications and metformin improved diabetes-related outcomes in overweight patients.


Type 2 diabetes isn't just "high sugar." It is a systemic disease affecting the heart, kidneys, eyes, nerves, liver and blood vessels. The best defence is still early screening, weight management, regular exercise, a high-fibre diet, adequate sleep and timely treatment.


Dr. Nishant Raizada, HOD, Endocrinology and Diabetes, Amrita Hospital, Faridabad