Analysis of energy density of food in relation to energy intake regulationin human subjects

The relationship between energy density (ED) of food and drink consumption ad libitum and energy intake (EI) was analysed. EI was taken as average dai ly EI over the long term, and as EI during a single meal. Moreover, the dis tribution of EI over three ED categories was analysed. Average daily EI was related to ED of the food and drinks when ED was strongly influenced by sp ecific macronutrients. When ED was strongly influenced by the weight of wat er, it was not related to EI. During a meal subjects monitored mainly weigh t, and to a lesser extent, the energy content of the food ingested. Therefo re, covertly manipulated ED of a meal affected EI directly. The impact of E D on EI was modulated by dietary behaviours such as restraint. Overt manipu lation of ED for 6 months showed that EI was adjusted to a decreased but no t to an increased ED in dietary-unrestrained subjects, and that EI was adju sted to an increased but not to a decreased ED in dietary-restrained subjec ts. Knowledge of ED was shown to lead to an inverse relationship between po rtion sizes and ED during a meal. Average daily EI consisted of a distribut ion of EI over the three different categories of ED, so that obese women at e more of foods with a high ED and less of foods with a low ED compared wit h normal weight women (and nutritional guidelines). In conclusion, ED affec ted daily EI by means of macronutrient specific effects. EI from a meal wit h an unknown ED can become inversely related to EI through learning or cond itioning. Therefore, the effect of ED on EI during a single meal observatio n cannot be extrapolated directly to the 24 h effect on El. With regard to the treatment of obesity, a conscious decreased consumption of foods high i n ED and an increase in consumption of low-ED food is necessary to decrease and subsequently maintain body weight, particularly in subjects with a sed entary lifestyle.