Indicator Of Hunger Research Articles

Effect of branched-chain amino acids on food intake and indicators of hunger and satiety- a narrative summary

Branched-chain amino acids (BCAA) found in protein are most notably known for their ability to increase protein synthesis, explaining their appeal to athletes seeking muscle hypertrophy, expedited recovery, and preservation of lean body mass. In addition to anabolic benefits, protein consumption has been implicated in the regulation of food intake, which represents an important variable in treating and preventing obesity. Protein-rich foods (such as dairy) have previously been linked to improved satiety and reduced food intake, however, there appear to be discrepancies in the effects of different protein types (for example whey versus casein) on appetite. One potential explanation for these differences is the varied amino acid composition of each protein type. Thus, one theory is that high levels of BCAA may be responsible in-part for the satiating properties of protein. Therefore, the purpose of this narrative review is to describe the effects of BCAA (both individually and in combination) on hormonal regulators of satiety including ghrelin, leptin, peptide tyrosine tyrosine (PYY), cholecystokinin (CCK), and glucagon-like peptide-1 (GLP-1). This report also summarizes the effect of BCAA on food intake and subjective measures of hunger. Several reports suggest BCAA stimulate leptin activity (secretion or sensitivity) and GLP-1 levels and suppress ghrelin levels. Similarly, intake is reduced, and subjective measures of hunger are often lower following consumption of BCAA. However, inconsistencies in experimental protocols and related findings make the true effect of BCAA on satiety and food intake difficult to discern, and therefor worthy of further investigation. • Protein-rich foods have previously been linked with satiety and reduced food intake. • BCAA may be responsible in-part for the satiating properties of protein. • BCAA may reduce food intake and subjective measures of hunger.

The eyes have it: Infant gaze as an indicator of hunger and satiation

Infant gaze serves as a measure of attention to food cues in adults and children and may play a role in signalling infant hunger and satiation. Maternal responsiveness to infant satiation cues, including gaze, supports healthy appetite development and may reduce obesity risk. However, mothers often experience difficulty in interpreting feeding cues, and there have been few attempts to study cues systematically. This study aimed to develop a reliable coding scheme for categorising and tracking infant gaze behaviours during complementary feeding (CF). Twenty infants aged between six and eighteen months were filmed during typical meals on two occasions at home. The Infant Gaze at Mealtime (IGM) coding scheme was devised from the analysis of a sample of videos, a piloting and testing process, and the feeding cues and developmental psychology literature. Inter and intra-rater reliability tests of the scheme with 20% of the study videos revealed high levels of reliability. When applied to the full sample of 225 video clips, the IGM coding scheme revealed a significant decrease over time in the frequency of infants gazing at food and a significant increase in exploratory gaze behaviour within a meal. These changes were consistent across main and dessert courses, suggesting they may be indicative of changes in infant feeding state. The results suggest that infant gaze may offer a means of identifying infant hunger and satiation and, as an easily observed behaviour, an effective tool for mothers and professionals for promoting responsive feeding.

Plantain: indicator of hunger and food shortage in families benefiting from food programs in Vigia del Fuerte, Colombia

To analyze the perception of hunger and food shortage in families benefiting from MANA (Food and Nutritional Improvement) food programs in Vigía del Fuerte, Colombia. Qualitative research, using focused ethnography as a method for collecting information. Individual interviews and discussion groups were used. Even though the communities that live by the Murrí River basin are protected from physical hunger due to the constant availability of plantain or musa, hunger is associated with the absence of meat or liga and the fact that they feel forced to eat empty musa. They also refer to hunger as the feeling of uneasiness caused by headache and stomachache. Despite the fact that the communities of Vigía del Fuerte have access to plantain throughout the year, thus protecting them from physical hunger, they do not consider it as food that could calm their hunger and free them from scarcity. This happens because its presence as the only food available reminds them, precisely, that they lack certain conditions and feel hunger.

Effects of Liquid Formula on Plasma Glucose, Insulin, and Ghrelin Levels in Healthy Humans with Mixed Meal Tests

Diet modulation is an important component of the treatment of type 2 diabetes. Glucerna SR is a complete nutritional product containing carbohydrates of low glycemic response with monounsaturated fats composing 24% of the total energy. The aim of this study was to examine the postprandial responses of plasma glucose, insulin, and ghrelin in a mixed meal test (MMT) of Glucerna SR and an ordinary meal (sandwich) in healthy human subjects. Twenty-one healthy human subjects, with a mean age of 24.0 ± 0.9 years were recruited. Anti-human ghrelin antibodies, YJC 1-19, were produced in rabbits by means of keyhole limpet hemocyanin conjugation. Steamed buns, sandwiches, and Glucerna SR were ingested over 3 separate days after fasting overnight. Blood was drawn either at 30 min or serially at 10, 20, 30, 60, 90, 120, and 180 min after meals as part of the MMT, and plasma glucose, insulin, and ghrelin were assayed. The results revealed that anti-serum YJC 1-19 was highly sensitive and specific to human ghrelin, and plasma ghrelin concentration was a proper indicator of hunger or satiety. At the 30 min point, sandwich ingestion resulted in the highest elevation of glucose and insulin, while steamed bun ingestion resulted in the least suppression of ghrelin. The MMT revealed that Glucerna SR ingestion resulted in lower glucose and insulin responses but similar ghrelin responses as compared to sandwich ingestion. In conclusion, the liquid formula of Glucerna SR induces a lower elevation of plasma glucose and insulin levels. The ingestion of Glucerna SR induces a similar decrease of plasma ghrelin levels, thus it does not trigger hunger sensations for 3 h.

Response of female broiler breeders to qualitative feed restriction with inclusion of soluble and insoluble fiber sources

SUMMARY To alleviate the feeling of hunger in broiler breeder hens, different types of fiber sources were used to increase feed quantity in Cobb 500 broiler breeder hens from 24 to 38 wk of age. Dietary treatments were a control diet and low-density diets through inclusion of wheat bran (WB), cellulose (CEL), pectin, and cottonseed meal. All diets were supplied an equal amount of AME, CP, Ca, P, and amino acids. Providing a diet with insoluble and soluble fiber sources increased the duration of feeding 2.4 and 3.8 times more than control group, respectively. For the entire experimental period, proportion of insoluble fiber sources (CEL and WB) resulted in more egg production than the control group. Cottonseed meal-fed birds displayed higher plasma triacylglycerol, cholesterol, and greater abdominal fat weight. Inclusion of insoluble fiber sources (CEL and WB) significantly decreased plasma corticosterone concentration, which is an indicator of hunger and frustration in birds. In spite of total nutrient intakes being equal once laying commenced, providing high-fiber diets with insoluble fiber sources can improve the reproductive performance of broiler breeder hens in early cycle of production period.

Do low-density diets improve broiler breeder welfare during rearing and laying?

Low-density diets may improve welfare of restricted fed broiler breeders by increasing feed intake time with less frustration of feed intake behavior as a result. Moreover, low-density diets may promote satiety through a more filled gastrointestinal tract, and thus feelings of hunger may be reduced. Broiler breeders were fed 4 different diets during the rearing and laying periods. Behavioral and physiological parameters were measured at different ages as indicators of hunger and frustration of the feeding motivation. A diet of 8.4 MJ/kg as compared with a standard diet of 10.9 MJ/kg extended feeding time and reduced stereotypic object pecking at 6 and 10 wk of age. Furthermore, compensatory feed intake at 12 wk of age was reduced. During lay, differences in behavior were observed between the treatments that could be attributed to differences in feeding time. However, birds fed the diet with the lowest energy content (i.e., 9.2 MJ/kg) had higher heterophil to lymphocyte ratios (H/L) at 40 wk of age compared with the other treatments, indicating that they experienced more stress during the laying period than the other treatments. This result could have been due to the very long feeding time of this treatment group during lay, which may be stressful. In conclusion, a low-density diet of 8.4 MJ/kg may reduce hunger and frustration in the first half of the rearing period. However, for substantial improvement of broiler breeder welfare during rearing, more extreme diet modifications are required.

Effect of scattered feeding and feeding twice a day during rearing on indicators of hunger and frustration in broiler breeders

Broiler breeders are routinely fed restricted during rearing which has a major negative effect on their welfare. They suffer from hunger and frustration from thwarting of feeding. The aim of this experiment was therefore to study if broiler breeder welfare can be improved by changes in the feeding system that can easily be applied in practical broiler breeder husbandry. We investigated the effects of scattered feeding in the litter and/or feeding twice a day on parameters of hunger and frustration in broiler breeders. Scattered feeding reduced the time spent object pecking but has no effect on other indicators of hunger like the compensatory feed intake, the plasma glucose/NEFA ratio and plasma corticosterone concentrations. Broiler breeders fed two meals a day show more walking, which may indicate food searching-related activity or frustration of the feeding motivation. Moreover, compensatory feed intake, the glucose/NEFA ratio and plasma corticosterone concentrations were similar in birds fed either one or two meals a day. It is unclear if the reduced time spent on object pecking, but the large proportion of time spent on foraging activities in scattered fed birds can be interpreted as reduced frustration and thus as an improvement of broiler breeder welfare. We conclude that scattered feeding, feeding twice a day and a combination of these two feeding strategies do not significantly improve broiler breeder welfare during rearing as indicators of hunger have not changed.

Mouth Color Signals Thermal State of Nestling Dark‐Eyed Juncos (Junco hyemalis)

AbstractIn many species of birds, nestlings have brightly colored mouths. Some studies have found that mouth color is related to hunger, and may serve to solicit feedings from parents. We devised two experiments to test the hypothesis that mouth color is an indicator of hunger in nestling dark‐eyed juncos (Junco hyemalis), and neither experiment produced results to support the hypothesis. We did find, however, that mouth redness saturation increased for the duration of our experiments (60 min). We devised a third experiment to investigate the effect of a different stressor, temperature. In the third experiment, mouth redness decreased in saturation when microenvironment temperature increased following a period of cooling. These findings suggest that mouth color indicates thermal state of nestling dark‐eyed juncos and may function as a signal to the female to brood them.

Stimulus generalization can be demonstrated in stimulation-bound feeders

Stimulus generalization has been suggested to be an indicator of hunger in some studies. Stimulation-bound feeders have been reported not to show generalization. Separate reports have indicated that some or all tail pinch-induced feeders do generalize. In this study, stimulation-bound and food-deprived feeders generalized along the stimulus dimension of food objects, consuming a nonpreferred although familiar food when the preferred food substance was removed, rather than engaging in a different behavior. Interestingly, competition tests indicated that food preference did not change following this experience. In contrast to other studies, an extensive Screening-Familiarization procedure was used and animals had to meet stringent Eating and Preference Criteria. Also, a large number of test sessions led to stable behavioral responses. It is suggested that stimulus generalization may not be an appropriate test of hunger.

Seasonal changes in aggression, hunger, and curiosity in ranch mink

Aggression, hunger, and curiosity of ranch mink (Mustela vison) were examined. The animals were divided into socialized animals (those visually isolated at 1 year of age) and unsocialized animals (those visually isolated at 10 weeks of age).Aggression was measured by placing two mink in a special cage and measuring the time until a fight or confrontation occurred. The effects of 0, 24, and 48 hours of food deprivation were measured in summer, fall, and winter. The number of trips made by each mink up a vertical cage to get food was used as an indicator of hunger. Levels of curiosity were determined by measuring the speed and pattern of exploration of a novel open-field situation. The breeding behaviors of experienced and inexperienced male mink were compared.Aggression in mink consisted of at least two offensive threats and, as in other animals, fighting was ritualized to a great extent. All young mink showed some adult aggressive patterns by 20 weeks of age. Aggression in males reached a peak at breeding season (March) and declined throughout the summer and fall, to a low point in November. Socialized males had lower aggressive levels than unsocialized males. Aggression in female mink reached a peak after the breeding season and declined to a low in winter. These cycles were likely caused by gonadal hormones in males and hormones from the corpora lutea in females.Both consumption and storage of food must be considered in determining hunger in mink. Hunger varied inversely with environmental temperature, reaching a peak in the winter and a low point in the summer. Immature animals had lower hunger drives than adult animals. Changes in body weights of mink centered around the breeding season.Curiosity decreased from summer to fall as did aggression. Unsocialized males had higher levels of curiosity than socialized males and females. Immature mink showed incomplete exploratory behavior and had lower curiosity scores than adult animals.