Objective: To explore the relative importance of a food's macronutrient composition, energy value, energy density, fiber content, weight, volume, sensory properties and rheology on hunger and food intake.
Design: Preloads of peanuts, peanut butter (rheology control), almonds (tree nut), chestnuts (macronutrient control), chocolate (sensory control), rice cakes (volume control), pickles (weight control) and no load (time control) were consumed by subjects in random order at weekly intervals and hunger was assessed over the subsequent 180 min. Free-feeding energy and macronutrient intake were monitored 24 h before and following preload ingestion.
Subjects: Twelve male and 12 female healthy, normal weight (12-28% body fat), adults (mean (s.d.) age 22 +/- 2.5 y) with low dietary restraint.
Results: Hunger ratings following consumption of the 2092 kJ (500 kcal) preloads of peanuts, peanut butter, almonds, chestnuts and chocolate were significantly lower than the low energy preloads or no preload condition, but with the exception of peanut butter, did not vary from each other. The rate of hunger recovery was consistent across all preloads so the overall impact of each food on hunger was determined by the initial drop it evoked. Total energy, but not macronutrient, compensation was observed with all preloads. Consequently, the fatty acid profile of the total diet reflected the composition of the preloads.
Conclusions: Energy content may be the primary determinant of a food's impact on hunger. Because macronutrient compensation is weak, a dietary supplement or substitute may influence the daily dietary nutrient profile.