The hormone insulin, which is produced by the beta cells of the pancreatic islets, regulates carbohydrate, fat and protein metabolism. When glucose generated due to the digestion of carbohydrate is released into the bloodstream, insulin is produced by the body. Under conditions of normal insulin reactivity, glucose is absorbed by the cells. When cells have an inhibited response to this hormone, a pathological condition known as insulin resistance occurs. Under this, excess blood sugar is not absorbed by the cells and results in symptoms such as polyphagia, polydipsia and polyuria. This is believed to occur due to a high intake of carbohydrates, mainly fructose. The diagnosis of insulin resistance is generally done by evaluating fasting insulin levels, glucose tolerance testing, hyperinsulinemic euglycemic clamp and modified insulin suppression test. Often a low carbohydrate diet and fasting helps in reversing insulin resistance. This book unravels the recent studies related to insulin resistance. It provides significant information of this condition to help develop a good understanding of its diagnosis and management. This book includes contributions of experts and scientists which will provide innovative insights into this metabolic condition.