Background: The manipulation of the composition of foods consumed as between-meal snacks may aid daily energy restriction.
Objectives: We compared the effects of the consumption of 2 energy-matched snack bars on appetite, energy intake (EI), and metabolic and endocrine responses. In addition, we investigated whether the acute effects of the consumption of snacks were maintained under free-living conditions and whether the habitual daily consumption of the snack over 14 d influenced these effects.
Design: Ten lean men [mean ± SD age: 30.7 ± 9.7 y; body mass index (in kg/m2): 23.2 ± 2.8] consumed a whey protein and polydextrose (PPX) snack bar or an isoenergetic control snack bar as a midmorning, between-meal snack for 14 consecutive days in a double-blind, randomized, crossover design. The two 14-d intervention phases were separated by a 14-d washout period. On the first (day 1) and last (day 15) days of each intervention phase, appetite, food intake, and blood metabolite and endocrine responses were assessed under laboratory conditions. Free-living EI was recorded on days 4, 8, and 12 of interventions.
Results: Total daily EI was significantly lower when the PPX snack was consumed during experimental days (10,149 ± 831 compared with 11,931 ± 896 kJ; P < 0.01), and daily EI remained lower when the PPX snack was consumed during the free-living part of the intervention (7904 ± 610 compared with 9041 ± 928 kJ; P< 0.05). The PPX snack was associated with lower glucose and ghrelin and higher glucagon-like peptide 1 and peptide tyrosine-tyrosine responses.
Conclusion: The manipulation of the composition of foods consumed as snacks is an effective way to limit subsequent EI.
Alex's Notes: Wait, you're telling me that consuming a high-quality protein (whey) with fiber induces satiety and thus lowers energy intake? Mind = blown. Okay, with the sarcasm out of the way, these "lean" men were, on average, 30 years old, 156 lbs, BMI = 23.2, and a habitual energy intake of roughly 3,000 kcal. Their diet was 16% protein, which translates to about 120g of protein daily (1.7 g/kg or .77 g/lb). So definitely adaquate basline protein, but we don't know if they were regular exercisers or not, and I still believe it is better to error on the side of caution. Thus, adaquate but not optimal. The snack bars themselves contributed 13g of whey with 6g of fiber, and were consumed 90 minutes before an all-you-can-eat pasta buffet. Needless to say, it reduced energy intake at the buffet and had beneficial effects on perceived fullness and satiety hormones (like GLP-1). More interesting, when consumed as a mid-morning snack daily for 2-weeks, the average energy intake was reduced by about 12%. Talk about a great snack for weight-loss.
Wait, aren't Questbars just milk/whey protein with fiber? You're kidding, and they supply 3x as much of each as the bar used in this study? AND they taste great. /end shameless plus.