Assessment of Obesity

IR at skeletal level is unique with association of abdominal obesity. They have more white fibres. Women with android obesity have not only android distribution of fat but also have their characteristics in skeletal muscle. White fibres are less insulin sensitive and have low capillary density.

Role Of Dietary Factors In Development Of Obesity And Type 2 Diabetes

High fat content in diet specially for those who have high propensity for development of obesity leads to increase in fat storage. It has been estimated that 1.6% increase in fat intake results in 10kg weight gain before there is increased fat oxidation to match intake.

Some ethnic groups like Japanese and Eskimos are protected from diabetes due to high intake of fish in the diet. Long chain omega-3 PUFA protects them. Other factors like high sucrose intake is also found to cause hyperinsulinemia & hyperglycaemia. Chromium is known to facilitate binding of insulin to insulin receptors and hence increases insulin sensitivity. Its deficiency can lead to decreased insulin sensitivity and diabetes. In trails chromium supplementation for 16 months showed no lowering of blood sugars but showed increase in HDL levels by 25%.

Role Of Malnutrition In Utero & In Infancy For Development Of Type 2 Diabetes

For many decades we have been only discussing the role of overnutrition in the pathogenesis of Type 2 diabetes. In recent years very interesting possibility and diabetogenic effects of malnutrition in utero has gained importance. This is known as ‘thriffy phenotype’. It is based on the observation that specific nutritional deficits in fetus and early fetal life later on predisposes to Type 2 diabetes by compromising function of beta cells if they change the life style and become obese in adult life. They do not become diabetic if they remain thin in adult life. Diabetes will occur only if they get abundant nutrition and pancreas cannot cope up with increased demands of insulin.

The following figure shows observation made by David Barker et al in the year 1997 which correlated BW & weight at 1 year of life to chances of development of Type 2 diabetes.

Plasma proinsulin levels are increased in obese Type 2 diabetics. This indicates increased insulin secretion. Raised levels of proinsulin correlate with increased cardiovascular morbidity and mortality. Other components of IRS also correlate with increased proinsulin level.

Role Of Leptin In Obese Type 2 Diabetics

Leptin is a by-product of Ob gene secreted by adipocytes. It acts on hypothalamus as a pattern. If these receptors are faulty then it can lead to faulty feeding pattern resulting in obesity. This in turn can lead to IR and IGT/Type 2 diabetics.

Treatment Of Obese Type 2 Diabetics

Type 2 diabetics are divided into obese & non-obese types as pathophysiology and treatment differs in these two categories. The energy dense food rich in fat and relatively low in carbohydrate and fibre, in a setting of low physical activity leads to obesity. Hence dietary management is a starting point in management of obese Type 2 diabetics.