Volume and variety: relative effects on food intake

Volume has been shown to be an important direct control of food intake, since larger volumes of food consumed prior to a meal can inhibit subsequent intake. Variety of food is known to stimulate food intake. The present study was designed to examine the relative effects of manipulating the volume of a soup preload in the context of providing either a single or a variety of sandwich fillings. Thirty participants (15 females; 15 males) attended the laboratory on 4 occasions to receive a low (f=240ml, 3.6kJ/g; m=300ml, 3.6kJ/g) or high (f=480ml, 1.8kJ/g; m=600ml, 1.8 kJ/g) volume tomato soup preload 30min before a sandwich lunch with either single or a variety of fillings. Overall, subjects reported significant differences in hunger and fullness as a function of volume manipulations but the satiety quotient (SQ: change in ratings divided by weight of soup) calculated just before lunch indicated a smaller SQ for high than for the low volume soup. Therefore, although subjective ratings were influenced by volume this was not sufficient to affect intake at lunch. Variety (2344 +/- 200 kJ) increased food intake at lunch compared to the single filling condition (2062 +/- 171 W), an enhancement by variety of 14%. In conclusion, lowering energy density and increasing volume by adding water failed to reduce intake at lunch. Clearly volume effects on intake rely both on amount consumed and energy density. As predicted, variety stimulated food intake and this occurred across volume conditions. (c) 2006 Elsevier Inc. All rights reserved.