This premise is entirely inaccurate as Diabetes is caused by increased blood glucose levels rather than body weight. Being overweight or obese is a serious risk factor but factors like family history, high blood pressure or a sedentary lifestyle put you at an increased risk of onset of Diabetes. Not all types of Diabetes are related to obesity.
For instance, Type 1 Diabetes is an autoimmune disease where the body’s own cells destroy the beta cells (responsible for insulin production) found in the pancreas. This results in a total lack of insulin in the body. The only treatment option is insulin injections. Type 1 Diabetes is usually seen in young adults and children. Though less common, people with Type 1 Diabetes are usually lean.
On the other hand, Type 2 Diabetes begins with insulin resistance (the cells fail to respond to normal levels of insulin). As it progresses, insulin productivity is hampered. The primary cause is abdominal obesity, lack of exercise and unhealthy eating habits. The majority of people have Type 2 Diabetes.
It is to be noted that the link between excess fat and Diabetes is related mainly to abdominal fat and less due to fat in the other areas of the body such as hands or legs. Therefore, a person may be thin, but if he/she has more abdominal fat then they are at an increased risk of Diabetes.
Excess abdominal fat makes the body resistant to insulin. Insulin is the hormone that can lower blood glucose. Insulin is an important hormone that delivers glucose (sugar) to our cells. When a person is overweight, the cells in the body become less sensitive to insulin released from the pancreas. Insulin resistance causes high blood glucose levels or Diabetes.
Abdominal obesity consists of many layers of fat. The first is below the skin; the second is inside the abdomen and third is the liver fat. All three lead to Type 2 Diabetes. Indian men with a waist circumference > 90 cm and Indian females with a waist circumference > 80 cm are said to have abdominal obesity which makes them more prone to Type 2 Diabetes.
Hence, while all people with Diabetes are not obese, abdominal obesity may contribute to Type 2 Diabetes. Losing weight, especially at the waist may help to control blood glucose levels.