Obesity is an epidemic and is on the rise. Statistics show that over 75% of American men are obese, as are 67% of adult American women. The current forecast is that 85% of Americans will be overweight, and half of them will be clinically obese by 2030. The increased obesity is associated with a number of chronic diseases that can increase mortality rates. These include cardiovascular disease and type-2 diabetes, along with some types of cancer. Indeed, for years type-2 diabetes was referred to as "Adult-onset diabetes" to differentiate it from Type-1 diabetes, which usually appeared early in life and was not associated with obesity. But in recent years, children as young as 11 have shown early signs of type-2 diabetes, such as insulin resistance, which is the forerunner of diabetes often called "pre-diabetes. In recent years, a clinical entity known as the metabolically healthy obese has emerged. Such people show few if any overt signs of ill health typically seen with obesity. Their blood lipids are within normal range, blood pressure is normal, and so on. Some doctors think, based on the positive health tests of metabolically healthy obese people, that having moderate levels of excess body fat is relatively harmless. However, a closer examination of just why these people rate as "metabolically healthy" reveals a pattern that is not common with most others who are obese. For example, the metabolically obese are active and exercise regularly. They also tend to eat better-balanced meals to support their increased physical activity levels. The regular exercise that they do boosts metabolic flexibility, which involves an easy shift into using either fat or carbohydrate as energy sources. A lack of such metabolic flexibility is common in metabolic diseases, such as the metabolic syndrome and diabetes. This increased activity largely accounts for their status as metabolically healthy, since it not only favors lower cardiovascular risk factors but treats the primary underlying problem related to having excess body fat: inflammation.
Scientists used to think that body fat was merely an inactive storage depot for excess calories. But research conducted over the past few years shows that body fat is anything but inactive. In fact, stored fat acts more like an endocrine organ, producing over 100 proteins collectively known as adipokines. Most of these adipokines produce inflammatory reactions in the body, which sets the stage for such chronic diseases as cardiovascular disease and cancer, the two main killer diseases. Leptin is one of the more familiar adipokines and is linked to obesity because it's involved in sending satiety signals to the brain that turn off appetite. Another adipokine works in reverse of the others by decreasing inflammation, as well as boosting insulin sensitivity. This substance, adiponectin, is increased by exercise and could be a major reason why the so-called metabolically healthy obese stay healthy. That is, such . . .