Diet, Obesity and Hypertension: An Hypothesis Involving Insulin, the Sympathetic Nervous System, and Adaptive Thermogenesis

The association of obesity and hypertension is well recognized. Although the frequency of hypertension in obese subjects varies depending upon the age, race, and sex of the population studied, as well as the definitions employed for hypertension and obesity, several reports suggest that as many as 50 to 60 percent of overweight people have high blood pressure 1, 2. Hypertension, more importantly, is probably the major factor accounting for increased cardio-vascular disease in the obese 3, 4. Despite the importance of the clinical problem, the fundamental nature of the association between obesity and hypertension has been obscure. Recent epidemiological and physiological studies, however, suggest that insulin and the sym-pathetic nervous system may be involved, and that the hypertension of obesity may be the unfortunate by-product of mechanisms that establish energy balance and limit weight gain. BODY FAT DISTRIBUTION, HYPERTENSION AND HYPERINSULINEMIA Not all obese are hypertensive. Recent anthropometric studies 5, 6 have confirmed earlier impressions 7 that cardiovascular disease in general, and hypertension in particular, is associated with fat accumulation in the abdomen and chest rather than in the gluteal and femoral regions. These studies have demonstrated convincingly that hypertension is associated