Learning about the energy density of liquid and semi-solid foods

Abstract

BACKGROUND: People learn about a food's satiating capacity by exposure and consequently adjust their energy intake. OBJECTIVE: To investigate the effect of energy density and texture on subsequent energy intake adjustments during repeated consumption. DESIGN: In a randomized crossover design, participants (n ¼ 27, age: 21 ± 2.4 years, body mass index: 22.2 ± 1.6 kg m À2) repeatedly consumed highly novel foods that were either low-energy-dense (LE: 30 kcal per 100 g) or high-energy-dense (HE: 130 kcal per 100 g), and either liquid or semi-solid, resulting in four product conditions. In each condition, a fixed portion of test food was consumed nine times as an obligatory part of breakfast, lunch and dinner on 3 consecutive days. All meals continued with an ad libitum buffet; food items for evening consumption were provided and the intake (kcal per day) was measured.RESULTS: Buffet intake depended on energy density and day of consumption of the test foods (day * energy interaction: P ¼ 0.02); daily buffet intake increased from day 1 (1745±577 kcal) to day 3 (1979±567 kcal) in the LE conditions; intake did not change in the HE conditions (day 1: 1523±429 kcal, day 3: 1589±424 kcal). Food texture did not affect the intake (P ¼ 0.56). CONCLUSIONS: Intake did depend on energy density of the test foods; participants increased their buffet intake over days in response to learning about the satiating capacity of the LE foods, but did not change buffet intake over days when repeatedly consuming a HE food as part of their meal. The adjustments in intake were made irrespective of the food texture. Keywords: food intake; satiety; satiation; texture; learned satiation; energy intake compensation INTRODUCTIONThe amount of food consumed is largely based on previous experiences with the specific food items. It is assumed that people learn about the energy density of a food by exposure and link the post-ingestive effects to the food's properties.1 This association enables people to predict the satiating capacity of foods 2,3 and to select an appropriate meal size. Studies that investigated intake adjustments in response to repeated consumption of low-(LE) or high-energy-dense (HE) foods, however, show inconsistent results (for example, refs 4 --6 vs refs 7 --9). When intake is not adjusted adequately, energy intake increases with increasing energy density. 10 In view of the prevention of overconsumption, it is of interest to better understand the elements that have a role in energy intake adjustment.Intake also depends on factors other than energy density, like food texture. It has been shown that liquids produce lower satiety sensations 11,12 and a weaker compensation of energy intake throughout the day, 13 compared with iso-caloric solid foods, and that ad libitum intake of a liquid food may be up to 30% higher, compared with a semi-solid food with similar energy content and palatability.14 Moreover, we observed a higher ad libitum intake of liquid foods after repeated consumption irrespective of energy density.

Food texture influences on satiety: systematic review and meta-analysis

“…In 16 studies 17 , 18 , 25 , 50 , 52 , 53 , 55 – 58 , 61 – 66 , manipulations of food forms that were included consisted of liquid versus solid or liquid versus semi-solid or semi-solid versus solid, and included chunky and pureed food. Food consisted mainly of vegetables, fruit, meat and beverage (fruit juices) and texture was manipulated by blending the food.…”

“…Nineteen studies measured food texture instrumentally, of which 14 assessed viscosity 17 , 20 – 22 , 24 , 29 , 55 , 56 , 59 – 62 , 64 , 67 , two measured lubricity indirectly by measuring friction coefficients 29 , 60 , one measured foam volume as a function of time 54 and one used aperture sieving 19 . Eleven studies assessed food texture using sensory evaluation, of which three studies have used a trained panel (11, 29, 33 panellists) 20 , 29 , 52 , four studies untrained (20, 20, 24, 32 panellists) 26 , 27 , 51 , 62 , and in two studies it is unclear whether it was a trained or untrained panel (20 panellists) 21 , 53 . Two studies did not publish or did not show the data 25 , 66 .…”

“…would lead to a greater suppression of appetite and reduced food intake. In fact, the qualitative synthesis showed that in half of the studies included in this systematic review food texture such as, solid form 17 , 50 , 52 , 53 , 55 , 57 , 62 , 65 , 66 , higher viscosity 20 – 22 , 24 , 51 , 59 , 60 , higher lubricity 29 , higher degree of complexity/heterogeneity 26 , 27 and aerated 54 food was reported to suppress appetite and reduce food intake. Likewise, the quantitative analysis (meta-analysis) clearly indicated a significant decrease in hunger with solid food compared to liquid food.…”

Effect of Replacing Sugar with Non-Caloric Sweeteners in Beverages on the Reward Value after Repeated Exposure

“…23,24). However, a recent review by Yeomans showed that studies investigating this phenomenon show mixed results [25].…”

Systematic review of the evidence for sustained efficacy of dietary interventions for reducing appetite or energy intake

“…Three other studies demonstrated adaptation (i.e. loss of a reported initial effect) in EI (17,27,28). Of these, only Wanders 2014 (17) also measured appetite and found the acute obesity reviews effects of treatment on appetite endured.…”