Food cravings and loss-of-control eating in youth: Associations with gonadal hormone concentrations

Neuroimaging and neuroendocrine insights into food cravings and appetite interventions in obesity

This article reviews the previous studies on the distinction between food cravings and appetite, and how they are regulated by hormones and reflected in brain activity. Based on existing research, food cravings are defined as individual preferences influenced by hormones and psychological factors, which differ from appetite, as they are not necessarily related to hunger or nutritional needs. The article also evaluates the neuroimaging findings about food cravings, and interventions to reduce food cravings, such as mindfulness training, alternative sweeteners, non-invasive brain stimulation techniques, cognitive-behavioral therapy, and imaginal retraining, and points out their advantages, disadvantages, and limitations. Furthermore, the article delves into the potential future directions in the field, emphasizing the need for a neuroendocrine perspective, considerations for associated psychiatric disorders, innovative clinical interventions, and emerging therapeutic frontiers in obesity management. The article outlines the neuro-endocrine basis of food cravings, including ghrelin, leptin, melanocortin, oxytocin, glucagon-like peptide-1, baclofen, and other hormones and their brain regions of action. The article argues that food cravings are an important target for obesity, and more research is needed to explore their complex characteristics and mechanisms, and how to effectively interact with their neuro-endocrine pathways. The article provides a new perspective and approach to the prevention and treatment of obesity.

Associated features of pediatric loss-of-control eating severity during a laboratory-based feeding paradigm

Laboratory-based loss-of-control eating (LOC-eating; i.e., feeling like one cannot stop eating) paradigms have provided inconsistent evidence that the features of pediatric LOC-eating are consistent with those of DSM-5-TR binge-eating episodes. Thus, this study investigated whether recent LOC-eating (in the prior month) and/or greater LOC-eating severity during a meal are positively associated with faster eating rate, energy intake when adjusting for hunger, post-meal stomachache and sickness (a proxy for eating until uncomfortably full), depression, and guilt. Recent LOC-eating was assessed via interview. Participants were presented with a buffet-type meal and instructed to "Let yourself go and eat as much as you want." Immediately following, youth reported on their experience of LOC-eating during the meal (LOC-eating severity). Eating rate (kcal/min) was computed by dividing total energy intake by the duration of the meal. Prior to and following the meal, youth reported hunger, sickness, and stomachache via sliding Visual Analog Scales, depression via the Brunel Mood Scale and guilt via the PANAS-X. Three-hundred-ten youth participated (61.2 % Female; 46.3 % non-Hispanic White, 12.96 ± 2.72 y). Recent LOC-eating was not significantly associated with any DSM-5-TR binge-eating feature during the laboratory meal (ps = 0.07-0.85). However, LOC-eating severity during the meal was positively associated with eating rate, eating adjusted for hunger, post-meal sickness and stomachache, and guilt (ps < 0.045). LOC-eating severity during a laboratory-based feeding paradigm meal, but not recent LOC-eating, was associated with several features of DSM-5-TR binge-eating episodes. Future studies should assess multiple components of LOC-eating to further characterize the phenomenology of pediatric LOC-eating.

Circadian variation of serum leptin and adipose tissue changes in children

BACKGROUND

Higher morning serum leptin values are associated with larger adipose tissue gains in children; however, it is unclear if leptin circadian variation is itself associated with adipose tissue changes during growth.

OBJECTIVE

We studied the association of circadian variation in leptin with change in total body fat mass (TBFM), total body percentage fat (%FM), and trunk fat mass (TrFM).

METHODS

Baseline serum samples for leptin were obtained every 3 h for 24 h from 130 children (baseline age 9.6 ± 2.5y; 51.1% male; BMI-Z 1.59) with mean follow-up of 11.1 ± 4.0y and underwent dual-energy x-ray absorptiometry. ANCOVA models examined change in TBFM, %FM, or TrFM as dependent variables and number of years of follow-up, sex, race, baseline age, pubertal status, initial visit body composition, and initial visit serum leptin circadian variables (maximal diurnal leptin [acrophase], diurnal amplitude, and percentage change of amplitude) as independent factors.

RESULT

Although initial visit mesor (24 h average) leptin was positively associated with initial visit TBFM (r2  = 0.78, p < 0.001), %FM (r2  = 076, p < 0.001), and TrFM (r2  = 0.71, p < 0.001), none of the circadian leptin variables studied was significantly associated with change in TBFM, %FM, or TrFM.

CONCLUSION

We found no evidence that circadian variation in serum leptin concentrations during childhood is associated with long-term changes in children's adiposity.

State negative affect in relation to loss-of-control eating among children and adolescents in the natural environment

Affect regulation theory proposes that loss-of-control (LOC)-eating is preceded by increases and followed by decreases in negative affect (NA), but empirical tests of this theory among pediatric samples in the natural environment are needed. Using an ecological momentary assessment approach, we conducted post-hoc analyses to examine LOC-eating severity reported during post-meal surveys in relation to the intensity of composite NA and NA components (anger, anxiety, depression, guilt) throughout the day for two weeks in a cohort of healthy children and adolescents. Multilevel models tested the associations among LOC-eating severity and NA components reported at pre-meal surveys (t-1), post-meal surveys (t), and lagged post-meal surveys (t+1). Models were adjusted for sex, age, race/ethnicity, height, fat mass, socioeconomic status, and time between the occurrence and report of eating episodes; post-meal analyses were also adjusted for pre-meal NA. Participants age 8-17 (N = 100; 55% female; 45% male; 12.83 ± 2.73y; 24% with overweight/obesity) recorded 2410 eating episodes. Pre-meal composite NA and NA components were not associated with LOC-eating severity at the subsequent meal. LOC-eating severity was positively associated with post-meal depression (β = 0.042, 95% CI = 0.007, 0.076) and guilt (β = 0.056, 95% CI = 0.017, 0.095), but not composite negative affect, anger, or anxiety. The positive association among LOC-eating severity and guilt persisted in lagged post-meal analyses (β = 0.075, 95% CI = 0.021, 0.128). Contrary to affect regulation theory and laboratory data, but consistent with prior ecological momentary assessment data in children and adolescents, pre-meal NA was not linked to subsequent LOC-eating. Increased guilt following meals may be a mechanism for the development of exacerbated disordered eating. Longitudinal studies may elucidate how NA is implicated in the etiology of pediatric eating disorders.

The effects of prefrontal vs. parietal cortex transcranial direct current stimulation on craving, inhibition, and measures of self-esteem

While prefrontal cortex dysfunction has been implicated in high food cravings, other cortical regions, like the parietal cortex, are potentially also involved in regulating craving. This study explored the effects of stimulating the inferior parietal lobule (IPL) and dorsolateral prefrontal cortex (DLPFC) on food craving state and trait. Transcranial direct current stimulation (tDCS) was administered at 1.5 mA for 5 consecutive days. Participants received 20 min of IPL, DLPFC, or sham stimulation (SHAM) each day which consisted of two rounds of 10-min stimulation, divided by a 10-min mindfulness task break. In addition, we studied inhibition and subjective psychological aspects like body image and self-esteem state and trait. To decompose immediate and cumulative effects, we measured the following on days 1 and 5: inhibition through the Go/No-go task; and food craving, self-esteem, and body appreciation through a battery of questionnaires. We found that false alarm errors decreased in the participants receiving active stimulation in the DLPFC (DLPFC-group). In contrast, false alarm errors increased in participants receiving active stimulation in the IPL (IPL-group). At the same time, no change was found in the participants receiving SHAM (SHAM-group). There was a trending reduction in craving trait in all groups. Momentary craving was decreased in the DLPFC-group and increased in IPL-group, yet a statistical difference was not reached. According to time and baseline, self-esteem and body perception improved in the IPL-group. Furthermore, self-esteem trait significantly improved over time in the DLPFC-group and IPL-group. These preliminary results indicate that tDCS modulates inhibition in frontoparietal areas with opposite effects, enhancing it in DLPFC and impairing it in IPL. Moreover, craving is moderately linked to inhibition, self-esteem, and body appreciation which seem not to be affected by neuromodulation but may rely instead on broader regions as more complex constructs. Finally, the fractionated protocol can effectively influence inhibition with milder effects on other constructs.

Food preferences throughout the menstrual cycle - A computer-assisted neuro-endocrino-psychological investigation

BACKGROUND

As eating behavior changes in relation to the menstrual cycle and weight changes with menopausal transition, ovarian hormones appear to be involved in regulating eating behavior. However, observations are contradictory and are difficult to compare, due to methodological problems related to nutritional epidemiology. To better understand the relationship between ovarian steroid hormones and eating behavior, our study evaluates women's responses to visual food cues at different points in the menstrual cycle with their specific serum estrogen/progesterone levels and women's responses in the case of strong estrogen changes in the context of fertility treatments.

METHODS

We collected data from 129 women, 44 of whom received in vitro fertilization (IVF) at the Department of Reproductive Endocrinology, University Hospital Zurich. A total of 85 women with natural cycles were recruited at the University Hospital Zurich (n = 37) and at the Hannover Medical School (n = 48). Our observational study used 4 different measurement time points across the natural cycle and 2 measurement time points in women with supraphysiological estradiol levels during fertility treatments. Using a second cycle, we then tested our results for replication. At these predefined time points, women were shown pictures of 11 categories of food, with 4 items for each category and blood samples for measurement of hormone levels were taken. Food preferences registered at the time of the investigation were indicated on a visual analogue scale (0-100).

RESULTS

We did not find any statistically significant association between women's serum hormone levels and the rating of visually presented food, either during the menstrual cycle or during fertility treatments after controlling for multiple testing (all p > 0.005). Ratings for fruits, vegetables, and carbohydrates showed a significant linear decline throughout the first menstrual cycle (p < 0.01), which did not replicate in the second cycle (p > 0.05). In contrast, the ratings for sweets showed a significant linear decline in both cycles (both p < 0.01), with a mean rating of 54.2 and 48.8 in the menstrual phase of the first and second cycle, respectively, to a mean rating of 47.7 and 43.4 in the premenstrual phase of the first and second cycle, respectively. During fertility treatments, no food rating showed a significant change (all p > 0.05). Mood such as negative and positive affects did not influence ratings for visual food cues neither throughout the menstrual cycles nor during fertility treatment.

CONCLUSIONS

Serum levels of estradiol and progesterone do not correlate with food ratings in women, even when estradiol levels are above the physiological level of a natural menstrual cycle. Since, except for sweets, significant changes in food ratings in a first cycle did not replicate in a second menstrual cycle, significant findings from the literature based on animal or human studies focusing on a single-cycle have to be interpreted with caution.

Heart Rate Variability and Laboratory-Based Loss-of-Control Eating in Children and Adolescents

Among youth, greater heart rate (HR) and lesser HR variability (HRV) are precursors to loss-of-control (LOC) eating episodes in the natural environment. However, there are limited data examining whether pre-meal HR and HRV are associated with greater LOC-eating in the laboratory setting. We therefore examined temporal relationships between pre-meal HR, frequency- and time-based metrics of pre-meal HRV, perceived LOC-eating, and energy intake during a meal designed to simulate a LOC-eating episode. Among 209 participants (54.5% female, 12.58 ± 2.72 years, 0.52 ± 1.02 BMIz), 19 reported LOC-eating in the prior month. Perceived LOC-eating during the laboratory meal was not significantly linked to pre-meal HR (p = 0.37), but was positively related to pre-meal HRV (ps = 0.02–0.04). This finding was driven by youth with recent LOC-eating, as these associations were not significant when analyses were run only among participants without recent reported LOC-eating (p = 0.15–0.99). Pre-meal HR and HRV were not significantly related to total energy intake (ps = 0.27–0.81). Additional research is required to determine whether early-stage pediatric LOC-eating is preceded by a healthy pre-meal stress response. Longitudinal studies could help clarify whether this pattern becomes less functional over time among youth who develop recurrent LOC-eating episodes.

Is There a Link between Balance and Body Mass Composition in Children and Adolescents?

School-age children are particularly prone to disturbances in body composition, because this is a period of intensive growth and a period in which correct habits are shaped, especially in relation to diet. This is why it is so important to diagnose emerging disorders early so as to implement therapeutic or educational activities. The aim of this study was to assess the relationship between the factors of body mass composition and body mass index (BMI), as well as the balance parameters in children and adolescents. The study group consisted of 1137 children aged 7 to 15. There were 559 girls and 578 boys among the subjects. The study used the Tanita 780 body mass composition analyser and the Zebris stabilometric platform. It was found that girls were characterized by a significantly higher content of adipose tissue (24.37% vs. 20.45%), while boys were characterized by a higher content of lean tissue (32.99% vs. 30.43%), muscle tissue (31.23% vs. 28.86%) and water (24.15% vs. 22.28%). Interestingly, the girls had better balance than their peers in all analyzed parameters (COF TTL.-616.72 vs. 661.50; CEArea-73.63 vs. 112.24; COF HD-3.44 vs. 4.23; COF VD-4.52 vs. 5.12). It turned out that among children in adolescence, a higher adipose tissue content and a higher BMI correlated with a smaller surface area (p < 0.05) defined by the center of gravity and smaller deviations of the center of gravity in the horizontal plane (p < 0.05). Sex and adolescence play an important role in differentiating both body composition and body balance. The results of this study allow us to conclude that children with higher BMI values have better balance. Due to the fact that these conclusions are inconsistent with those of other researchers, it will be worth continuing the research (e.g., on a different population group) in order to confirm the results and to draw far-reaching conclusions.

Breaking It Down: Investigation of Binge Eating Components in Animal Models to Enhance Translation

Binge eating (BE) is a core eating disorder behavior that is present across nearly all eating disorder diagnoses (e. g., bulimia nervosa, binge eating disorder, anorexia nervosa binge/purge subtype), and is also widely present in the general population. Despite the prevalence of BE, limited treatment options exist and there are often high rates of relapse after treatment. There is evidence showing that genetic factors contribute to the heritability of BE and support for biological contributions to BE. However, more work is needed to fully understand neurobiological mechanisms underlying BE. One approach to target this problem is to separate BE into its distinct clinical components that can be more easily modeled using pre-clinical approaches. To date, a variety of animal models for BE have been used in pre-clinical studies; but there have been challenges translating this work to human BE. Here, we review these pre-clinical approaches by breaking them down into three clinically-significant component parts (1) consumption of a large amount of food; (2) food consumption within a short period of time; and (3) loss of control over eating. We propose that this rubric identifies the most frequently used and effective ways to model components of BE behavior using pre-clinical approaches with the strongest clinical relevance. Finally, we discuss how current pre-clinical models have been integrated with techniques using targeted neurobiological approaches and propose ways to improve translation of pre-clinical work to human investigations of BE that could enhance our understanding of BE behavior.