Diabetes mellitus is one of the most important diseases prevailing in the community. In this book, for better understanding, it will be called as diabetes. It is causing huge financial burden on the community. Worldwide it is one of the leading non-communicable diseases.

Diabetes is a disease condition where blood glucose (sugar) levels will be more than the normal range. Insulin is a hormone produced from pancreas, especially from beta cells. Insulin will maintain normal blood sugars by making appropriate usage of blood sugars by body cells. Basically diabetes occurs either due to absolute insulin deficiency in the body or due to relative insulin deficiency with defective action of available insulin due to insulin resistance in body tissues.

It is affecting the people all over the World. It is most prevalent in Asian countries like China and India.

Prevalence of diabetes is increasing day by day. Number of the patients affected by diabetes increasing in both urban and rural, men and women, and also in adults and kids. Change in food habits, lack of physical activity, environmental factors and also increased awareness among people and treating doctor may be responsible for this continuous increasing number of people affected by diabetes mellitus.

It gives me great pleasure to draft foreword for "Know Your Diabetes for Happy Life" by Dr. Ashok. Venkatanarasu. Diabetes mellitus is non-communicable (NCD), which affects a large part of the population. Majority of the population is at the peak of their productivity (type 2 diabetes mellitus). Unfortunate part is that some children also get affected with a type of diabetes (type 1 diabetes), which presents with high glucose (sugar) in blood and can be managed only with injections of insulin.

Like many other NCDs there was no effective treatment till early 20th century, when insulin was separated from pancreas, and used for treatment of diabetes (Discovery of insulin, 1921). After that many tablets and pills were discovered which worked in type 2 diabetes mellitus.

Next major breakthrough in management of diabetes mellitus came with discovery of glucometers. Till then blood glucose (blood sugar) could only measured in big laboratories, with big machines that measure blood glucose with help of chemical reactions. The turn around time for these labs and machines used to be 4-6 hours in good hospitals. With arrival of glucometers, getting blood glucose report is fast and simple. Most of the patients, who use insulin, use glucometers at home to get an idea of how good (or bad) is their control of blood glucose.