Appetite-Related Hormones and Subjective Feelings of Hunger and Satiety in Adults Who Regularly Consume Dairy and Those Who Limit Dairy Consumption

Objectives To compare self-reported feelings of hunger and fullness with biological markers associated with appetite and satiety in men and women who are habitual dairy consumers (DC) vs limited dairy consumers (LD). We hypothesize that the DC group will have different appetite perceptions along with different concentrations of the hunger hormone, ghrelin, and the anabolic hormone, insulin, before and following a mixed meal challenge. Methods Adults from a cross-sectional study who completed the Block food frequency questionnaire were categorized as DC (n = 40, consumed >2 cup-eq/d of milk, yogurt, and/or cheese), or LD (n = 37, consumed < ½ cup-eq/d of dairy). On a test day, overnight fasted and postprandial blood samples were collected after a (non-dairy) mixed meal challenge at 30 min, 3h, and 6h. Feelings of hunger, fullness, desire to eat, and prospective consumption were measured by visual analog scales (VAS) in the fasted state, and immediately following the mixed meal at 20 min, 40 min, 1h, 1.5h, 2h, 3h, 4h, 5h, and 6 h. Differences in VAS ratings, fasting glucose, insulin, and ghrelin, and 6-h incremental area under the curve (iAUC) between groups were analyzed using t-tests. Results The DC group had lower mean fasting ghrelin (P < 0.001) and higher fasting glucose (P < 0.05) compared to LD. Fasting insulin levels were not different between groups (P = 0.87), nor were there differences for 6-h iAUC for glucose, ghrelin, or insulin. Hunger, fullness, desire to eat, and prospective consumption, summarized as 6-h AUC, were not different between groups. No correlations were found between hormone concentrations and feelings of hunger, fullness, desire to eat, or prospective consumption, at fasting or 30 min, 3h or 6h following meal challenge. Conclusions Regular consumption of ≥2 cup-eq. of dairy was associated with a reduced fasting ghrelin that might signal less hunger compared to low dairy consumers, but no relationship between ghrelin and hunger was found. The postprandial response in ghrelin, glucose, and insulin were not influenced by habitual dairy consumption. Funding Sources Funding was provided by the United States Department of Agriculture and Arla Foods Inc.

A 1-week diet break improves muscle endurance during an intermittent dieting regime in adult athletes: A pre-specified secondary analysis of the ICECAP trial

Athletes undergoing energy restriction for weight/fat reduction sometimes apply ‘diet breaks’ involving increased energy intake, but there is little empirical evidence of effects on outcomes. Twenty-six resistance-trained athletes (11/26 or 42% female) who had completed 12 weeks of intermittent energy restriction participated in this study. Participants had a mean (SD) age of 29.3 (6.4) years, a weight of 72.7 (15.9) kg, and a body fat percentage of 21.3 (7.5) %. During the 1-week diet break, energy intake was increased (by means of increased carbohydrate intake) to predicted weight maintenance requirements. While the 1-week diet break had no significant effect on fat mass, it led to small but significant increases in mean body weight (0.6 kg, P<0.001), fat-free mass (0.7 kg, P<0.001) and in resting energy expenditure, from a mean (and 95% confidence interval) of 7000 (6420 to 7580) kJ/day to 7200 (6620 to 7780) kJ/day (P = 0.026). Overall, muscle endurance in the legs (but not arms) improved after the diet break, including significant increases in the work completed by the quadriceps and hamstrings in a maximum-effort 25-repetition set, with values increasing from 2530 (2170 to 2890) J to 2660 (2310 to 3010) J (P = 0.018) and from 1280 (1130 to 1430) J to 1380 (1220 to 1540) J (P = 0.018) following the diet break, respectively. However, muscle strength did not change. Participants reported significantly lower sensations of hunger (P = 0.017), prospective consumption (P = 0.020) and irritability (P = 0.041) after the diet break, and significantly higher sensations of fullness (P = 0.002), satisfaction (P = 0.002), and alertness (P = 0.003). In summary, a 1-week diet break improved muscle endurance in the legs and increased mental alertness, and reduced appetite and irritability. With this considered, it may be wise for athletes to coordinate diet breaks with training sessions that require muscle endurance of the legs and/or mental focus, as well as in the latter parts of a weight loss phase when increases in appetite might threaten dietary adherence. Trial registration: Australian New Zealand Clinical Trials Registry Reference Number: ACTRN12618000638235 anzctr.org.au.

Effects of energy balance on appetite and physiologic mediators of appetite during strenuous physical activity: secondary analysis of a randomized crossover trial

Energy deficit is common during prolonged periods of strenuous physical activity and limited sleep, but the extent to which appetite suppression contributes is unclear. The aim of this randomized crossover study was to determine the effects of energy balance on appetite and physiologic mediators of appetite during a 72-hr period of high physical activity energy expenditure (PAEE, ˜2300kcal/d) and limited sleep designed to simulate military operations (SUSOPS). Ten men consumed an energy-balanced diet while sedentary for 1d (REST) followed by energy balanced (BAL) and energy deficient (DEF) controlled diets during SUSOPS. Appetite ratings, gastric emptying time (GET), and appetite-mediating hormone concentrations were measured. Energy balance was positive during BAL (18±20%) and negative during DEF (-43±9%). Relative to REST, hunger, desire to eat and prospective consumption ratings were all higher during DEF (26±40%, 56±71%, 28±34%, respectively), and lower during BAL (-55±25%, -52±27%, -54±21%, respectively; Pcondition<0.05). Fullness ratings did not differ from REST during DEF, but were 65±61% higher during BAL (Pcondition<0.05). Regression analyses predicted hunger and prospective consumption would be reduced and fullness increased if energy balance were maintained during SUSOPS, and energy deficits of ≥25% would be required to elicit increases in appetite. Between-condition differences in GET and appetite-mediating hormones identified slowed gastric emptying, increased anorexigenic hormone concentrations, and decreased fasting acylated ghrelin concentrations as potential mechanisms of appetite suppression. Findings suggest that physiologic responses that suppress appetite may deter energy balance from being achieved during prolonged periods of strenuous activity and limited sleep.

Severe Sleep Restriction Suppresses Appetite Independent of Effects on Food Intake-Regulating Hormones

Objectives Several nights of moderate (4–5 hr/night) sleep restriction increases appetite and energy intake, and may alter circulating concentrations of food intake-regulating hormones. Whether more severe sleep restriction has similar effects is undetermined. This study aimed to determine the effects of severe, short-term sleep restriction on appetite and food intake-regulating hormones. Methods Randomized, crossover study in which 18 healthy men (mean ± SD: BMI 24.4 ± 2.3 kg/m2, 20 ± 2 yr) were assigned to three consecutive nights of sleep restriction (SR; 2 hr sleep/night) or adequate sleep (AS; 7–9 hr sleep/night) with controlled feeding and activity throughout the 3-day period. On day 4, participants consumed a standardized breakfast. Appetite ratings, and circulating ghrelin, peptide-YY (PYY), glucagon-like peptide (GLP-1), insulin, and glucose concentrations were measured before and for 4hr after the meal. Ad libitum energy and macronutrient intakes were then measured at a provided buffet lunch. Results Median PYY (–21%) and GLP-1 (–14%) concentrations were lower, and median glucose (3%) concentrations were higher after SR relative to after AS (main effect of condition, P &lt; 0.05; condition-by-time interaction, P = NS). Ghrelin and insulin did not differ between conditions. Mean hunger (–23%), desire to eat (–23%), and prospective consumption (–18%) ratings were all lower, and mean fullness (27%) ratings were higher after SR relative to after AS (main effect of condition, P &lt; 0.05; condition-by-time interaction, P = NS). Ad libitum energy intake at the lunch meal was 14% lower after SR relative to after AS (–332 kcal [95% CI: −479, −185] P &lt; 0.001), but macronutrient composition did not differ. Conclusions In contrast with reported effects of moderate sleep restriction, severe sleep restriction reduced appetite and energy intake. Appetite suppression was likely not due to the observed differences in food intake-regulating hormones as sleep-restriction induced reductions in PYY and GLP-1 concentrations would be expected to increase appetite. Funding Sources US Army MRDC. Authors’ views do not reflect official DoD or Army policy.

Suppression of Oral Sweet Sensations during Consumption of Sweet Food in Humans: Effects on Gastric Emptying Rate, Glycemic Response, Appetite, Food Satisfaction and Desire for Basic Tastes

Suppression of oral sweet sensation (OSS) acutely reduces intake of sweet-tasting food due to lower liking. However, little is known about other physiological responses during both the prandial and postprandial phase. Here, we explored the effects of Gymnema sylvestre (GS)-based suppression of OSS of several types of sweet-tasting food (muffin, sweet yogurt, banana) on gastric emptying, blood glucose (BG), plasma insulin (PI), appetite indices (hunger, fullness and prospective consumption), satisfaction and desire for tastes. Fifteen healthy subjects (22 ± 3 years, 9 women) took part in the study. Subjects rinsed their mouth with either GS solution or distilled water before eating the sweet-tasting food. Subjects felt decreased sweet taste intensity and reduced taste liking associated with GS rinsing after consuming each food, compared with rinsing with distilled water (p < 0.05). Gastric emptying, BG, PI and appetite indices during and after the prandial phase did not significantly change with GS rinsing compared to rinsing with distilled water (p > 0.05). Higher desire for sweet taste as well as lower satisfaction (p < 0.05) in the postprandial phase were observed with GS rinsing. These results suggest that the suppression of OSS does not affect gastric emptying, glycemic response and appetite during and after consumption of sweet-tasting food.

Very Low and Higher Carbohydrate Diets Promote Differential Appetite Responses in Adults with Type 2 Diabetes: A Randomized Trial

ABSTRACT Background Effects of very low carbohydrate (VLC) diets on appetite response in individuals with type 2 diabetes remain unclear. Objective A secondary analysis was conducted to determine appetite responses to an energy-restricted [30% of energy (%E) deficit] very low carbohydrate (VLC) diet compared with a higher carbohydrate (HC) diet in adults who were overweight or obese with type 2 diabetes. Methods Forty-four men and 40 women (mean ± SD, age: 58.7 ± 6.6 y; weight: 100.4 ± 15.5 kg; BMI: 34.5 ± 4.1 kg/m2; glycated hemoglobin: 7.3 ± 1.0%; duration of diabetes: 6.7 ± 5.6 y) were randomly assigned to diets categorized as VLC [14%E carbohydrate (&lt;50 g/d), 28%E protein, 58%E fat (&lt;10%E saturated fat)], or energy-matched HC [53%E carbohydrate, 17%E protein, 30%E fat (&lt;10%E saturated fat)] combined with progressive multicomponent exercise (60 min; 3 d/wk). Body weight, average weekly “daily fasting” and “daily overall” appetite perceptions (hunger, fullness, prospective consumption, and desire to eat—visual analog scales) were assessed at baseline and after 4 and 16 wk. Changes between diets over time were assessed using repeated measures ANOVA. Results Significant decreases in body weight did not differ between groups (VLC: −11.0 ± 5.4 kg/16 wk compared with HC: −10.1 ± 4.3 kg/16 wk, P = 0.40). Compared with HC, VLC had greater decreases in “daily overall” ratings of fullness (P time × diet &lt; 0.01), such that scores were higher in HC at Week 4 (VLC:48 ± 3 vs HC:56 ± 3 mm, P = 0.001) and 16 (VLC:51 ± 2 vs HC:57 ± 3 mm, P = 0.019). Compared with HC, VLC had greater increases in prospective consumption ratings (P time × diet = 0.03), such that scores were lower in HC at Week 4 (VLC:33 ± 2 vs HC:28 ± 2 mm, P = 0.008), but not at Week 16 (VLC:33 ± 2 vs HC 31 ± 2 mm, P = 0.289). Conclusions In the context of energy restriction, both HC and VLC energy-matched diets promoted comparable effects on fasting perceptions of appetite, but the HC diet resulted in greater “daily overall” fullness and reduced prospective consumption. Further research is required to evaluate the effects of ad libitum diets differing in amounts of carbohydrate on appetite response in populations with type 2 diabetes. This trial was registered at www.anzctr.org.au as ACTRN12612000369820.

Associations between sweet taste function, oral complex carbohydrate sensitivity, liking and consumption of ad libitum sweet and non-sweet carbohydrate milkshakes among female adults

Excess energy intake is recognised as a strong contributing factor to the global rise of being overweight and obese. The aim of this paper was to investigate if oral sensitivity to complex carbohydrate relates to ad libitum consumption of complex carbohydrate foods in a sample group of female adults. Participants’ ((n 51 females): age 23·0 (sd 0·6) years (range 20·0–41·0 years); excluding restrained eaters) sensitivity towards maltodextrin (oral complex carbohydrate) and glucose (sweet taste) was assessed by measuring detection threshold (DT) and suprathreshold intensity perception (ST). A crossover design was used to assess consumption of two different iso-energetic preload milkshakes and ad libitum milkshakes – (1) glucose-based milkshake, (2) maltodextrin-based milkshake. Ad libitum intake (primary outcome) and eating rate, liking, hunger, fullness and prospective consumption ratings were measured. Participants who were more sensitive towards complex carbohydrate (maltodextrin DT) consumed significantly more maltodextrin-based milkshake in comparison with less-sensitive participants (P = 0·01) and this was independent of liking. Participants who had higher liking for glucose-based milkshake consumed significantly more glucose-based milkshake in comparison with participants with lower hedonic ratings (P = 0·049). The results provide support regarding the role of the oral system sensitivity (potentially taste) to complex carbohydrate and the prospective to overconsume complex carbohydrate-based milkshake in a single sitting.

Difficulties in Translating Appetite Sensations Effect of Turmeric-Based Beverage When Given Prior to Isoenergetic Medium- or High-Fat Meals in Healthy Subjects

The established effect of turmeric and its curcuminoids on appetite sensations was previously shown to be mediated by gut hormones release. In in vitro and preclinical studies, curcumin was shown to induce GLP-1 secretion and improve postprandial glycemia. In humans, consumption of 220 mL turmeric-based beverage (TUR, containing 185 mg gallic acid equivalents (GAE)) prior to white wheat bread (WWB, 50 g available carbohydrate) reduced early postprandial glucose levels and induced peptide tyrosine–tyrosine (PYY) release, as well as lowered ‘desire to eat’ and ‘prospective consumption’ in a postprandial setting, compared to control. In the present study, 12 healthy participants (5 men, 7 women) were admitted. An identical beverage was given and consumed prior to isoenergetic (423 kcal) medium-fat (MF) or high-fat (HF) meals. Appetite sensations including perceived ‘hunger’, ‘desire to eat’, ‘satiety’, ‘fullness’, ‘prospective consumption’, and ‘thirst’ were measured using visual analogue scales. MF induced 18% (p = 0.039) higher ‘satiety’ compared to HF. TUR consumption prior to either MF or HF did not modulate the perceived appetite sensations. Whether macronutrient-induced appetite sensations override the actual turmeric effects warrants further investigation.

The Response of More Health Focused and Less Health Focused People to a Physical Activity Calorie Equivalent Label on Discretionary Snack Foods

A Physical Activity Calorie Equivalent (PACE) label shows the minutes of physical activity required to burn off the caloric content of a particular food. This study investigated the influence of PACE labelling on liking and consumption of discretionary snack foods in a group of more health focused and less health focused consumers. Participants (n = 97) tasted and rated (i.e., liking, prospective consumption) a range of snack foods with or without a PACE label. Total sampling consumption was also measured. Participants completed a shortened version of the International Physical Activity Questionnaire and the General Health Interest Scale questionnaire. Paired samples t-test, independent samples t-tests, a General Linear Model and Chi-Square tests were used to check for statistical significance. For more health focused participants (n = 57), the PACE label decreased only liking (p = 0.02). The PACE label was not effective in reducing liking (p = 0.49), prospective consumption (defined as the amount of the sample participants thought that they could consume) (p = 0.10) or consumption (p = 0.41) of energy-dense discretionary snack foods for less health focused individuals (n = 40). The level of participants’ physical activity did not facilitate the influence of PACE labelling on liking, consumption or prospective consumption. The PACE label was found to not be effective among less health focused individuals or the overall sample population. Therefore, the PACE label may not be an effective labelling strategy to reduce the liking or consumption of discretionary snack foods.

Physical activity-equivalent label reduces consumption of discretionary snack foods

ObjectiveThe present research aimed to investigate the impact of the physical activity calorie equivalent (PACE) front-of-pack label on consumption, prospective consumption and liking of familiar and unfamiliar discretionary snack foods.DesignIn a within-subject randomised design, participants tasted and rated liking (9-point hedonic scale) and prospective consumption (9-point category scale) of four different snack foods with four different labels (i.e. blank, fake, PACE, PACE doubled) and four control snack foods. The twenty snack foods were presented during two 45 min sessions (i.e. ten snack foods per session) which were separated by one week. The amount participants sampled of each snack food was measured.SettingThe study was conducted in the Centre for Advanced Sensory Sciences laboratory at Deakin University, Australia.SubjectsThe participants were 153 university students (126 females, twenty-seven males, mean age 24·3 (sd 4·9) years) currently enrolled in an undergraduate nutrition degree at Deakin University.ResultsWhen the PACE label was present on familiar snack foods, participants sampled 9·9 % (22·8 (sem 1·4) v. 25·3 (sem 1·5) g, P=0·03) less than when such label was not present. This was in line with a decreased prospective snack food consumption of 9·1 % (3·0 (sem 0·2) v. 3·3 (sem 0·2) servings, P=0·03). Such pattern was not seen in unfamiliar snacks.ConclusionsThe PACE label appears to be a promising way to decrease familiar discretionary snack food consumption in young, health-minded participants.