Obesity is one of themajor risk factor of health (1) that led to increased metabolic complications ofobesity including type 2 diabetes, metabolic syndrome, impaired glucosetolerance, insulin resistance, hyperglycemia, cardiovascular diseases and cancer (2). Previous studies have shown that theprevalence of obesity and overweight is increasing significantly, asapproximately 600 million people were obese throughout the word in 2014 (3) and it will increase almost 7-10% amongadult in 2020 (4). However, weight maintenance has determineby whole energy intake (3), managing the energy density of diets is anovel approach to reduction of body weight (5).Energydensity (ED) has an important effect in the regulation of energy intake (EI) (6), indeed EI will decrease by reducing energydensity (ED) of a diet (7). ED of diets defined as the energy contentof foods (kJ or kcal) per unit weight of foods (g) (8). Diets with lower ED include whole grains,vegetables, fruits, low-fat dairies and lean meats (9). Lower ED has a beneficial effect on weight reduction,weight maintenance and waist circumference (1; 10), also it prevents from passive over-eating,abdominal obesity, weight gain and, excessive adiposity (10). But its relationshipwith RMR isless known.
Some studies have shown the association between RMR and the level of somehormones in the body. Previous evidence have demonstrated that inoverweight and obese people vaspin is increased and adiponectin is reduced,that they are two adipose-derived hormones (11). Recent studies havedemonstrated that there is mediatory effect of vaspin and adiponectinwith restingmetabolic rate (RMR) through visceral fat and fat mass (12; 13).RMR usually have the largest component of daily energy requirements (approximately 65 to 70%) (14), and it consists of resting Metabolic Rate, physical activity and the thermiceffect of food (15). RMR is associated with fat-free mass (FFM), fatmass (FM), leptin, adiponectin, and body weight (16; 17; 18).