Avoiding hunger or attaining fullness? Implicit goals of satiety guide portion selection and food intake patterns.

Although implicit theories have been studied in the context of personal traits, there has been limited investigation of their role in physiological domains such as appetite. Subjective feelings and affective states can function as goals and desired end states that individuals regulate their behaviors to attain. Likewise, different conceptualizations people maintain for the subjective experience of satiety (i.e., terminating hunger or attaining fullness) may also predict individual variations in eating behavior. We examined whether portion selection and food intake were guided by such implicit goals pertaining to the nature of satiety. Across 3 studies, we observed that individuals report distinct subjective requirements (degrees of fullness) to attain different states of satiety (stop hunger, feel comfortably full, feel completely full), suggesting that these states reflect independent goals or outcomes. Importantly, personal requirements to feel completely full (compared to stop hunger or feel comfortably full) were observed to be the strongest predictor of portion sizes selected in Study 1 (B = 1.17, p < .001) and Study 2 (B = 4.26, p = .004), and the quantity of energy consumed from a meal in Study 2 (B = 3.07, p = .01). Yet, experimentally activating a situational goal to stop hunger (vs. feel full) produced the selection of smaller portion sizes, F(1, 41) = 5.64, p = .02, and personal requirements to stop hunger to become the dominant predictor of portion selection patterns in Study 3 (B = 0.43, p = .005). These findings reveal that eating behaviors of modern consumers may be guided by a predominant goal to attain the subjective experience of complete fullness, although this implicit goal may be malleable to situational demands.

The role of perceived stress and gender on portion selection patterns.

Stress is linked to increased preferences and consumption of palatable energy dense foods, particularly among females. Despite the role of stress on potentially obesogenic eating habits, its effect on pre-meal planning, such as the selection of portion sizes, remain unknown. Here, we investigated the relationship between perceived stress, gender, and intended portion sizes for diverse foods. Across two studies, increased perceived stress predicted larger (higher energy) intended portion sizes across a variety of food items among females, but not males. Additionally, for females, increased perceived stress was associated with lowered expectations of the satiety of foods presented, suggesting a potential mechanism by which stress may influence decisions about portion size. These findings reveal that the potentially obesogenic effects of stress on food judgments and behaviours (particularly among females) are not only expressed within meals, but also during more deliberate stages of planning that precedes meals.

Low subjective socioeconomic status stimulates orexigenic hormone ghrelin - A randomised trial.

Recent evidence suggests that lower perceived socioeconomic status is linked to increased appetite and intake of greater calories. Yet, whether insecurity of socioeconomic resources directly influences regulatory systems of appetite and energy intake is not known. Considering psychological states, mindsets and beliefs have shown to meaningfully affect physiological responses to food, the present study tested the hypothesis that low subjective socioeconomic status (SSS) will have a direct influence on physiological responses, such as appetite-related hormones (ghrelin, pancreatic polypeptide and insulin). Forty-eight healthy males were randomly (crossover, counterbalanced) assigned, to two experimental conditions where participants were either experimentally induced to feel low SSS or not (control; CON). Feelings of low SSS resulted in an increase in active ghrelin (an orexigenic hormone) following the SSS manipulation compared with baseline, while no change in active ghrelin was observed in CON. Furthermore, participants reported lower fullness and satiety following low SSS compared with CON. Our findings demonstrate that SSS may influence hunger regulation and appetite, and suggest that physiological systems regulating energy balance (i.e. caloric resources) may also be sensitive to perceived deprivation or imbalances in critical non-food resources (socioeconomic resources).

Personal relative deprivation increases self-selected portion sizes and food intake.

Cues and experiences of the deprivation of financial/material resources have been associated with increased caloric intake and risk for overweight/obesity. Given that social comparisons may serve as a powerful reference for the adequacy of one's standing and resources, the present research tested whether subjective feelings of personal relative deprivation (PRD) or "losing out" to others stimulates calorie selection and intake. Study 1 demonstrated that self-reported chronic experiences of PRD positively predicted calories selected for a portion and consumed during an ad-libitum meal. Study 2 revealed that experimentally-induced PRD resulted in an increase in the amount of calories selected on a portion selection task and a stronger desire to consume the foods. Consequently, these findings demonstrate that chronic and acute subjective deprivation of non-food resources may contribute to socioeconomic gradients in obesity, and that perceived social inequality may have inherently obesogenic properties that promote excess calorie intake.