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Appetite hormones may play a significant role in neuronal excitability and synaptic plasticity and may also affect brain function development. This study aimed to explore the role of appetite hormones in attention deficit/hyperactivity disorder (ADHD), including aspects of pathophysiology, pharmacotherapy, and side effects. We recruited 119 patients with ADHD who were undergoing methylphenidate treatment (ADHD+MPH), 77 unmedicated ADHD patients (ADHD-MPH), and 87 healthy controls. Blood samples were collected from all participants to examine serum levels of orexin A, ghrelin, leptin, and adiponectin. Behavioral symptoms were assessed using the Swanson, Nolan, and Pelham Rating Scale, and visual and auditory attention were evaluated using computerized neuropsychological tests. The side effects of methylphenidate treatment were measured using Barkley's Side Effects Rating Scale. Orexin levels in the control group were significantly higher than in the ADHD-MPH (p=0.037) and ADHD+MPH (p<0.001) groups; additionally, orexin levels in the ADHD-MPH group were significantly higher than in the ADHD+MPH group (p=0.032). Leptin levels in both the ADHD+MPH (p=0.011) and ADHD-MPH (p=0.011) groups were significantly lower than in the control group. Ghrelin levels were positively associated with auditory attention across all ADHD groups (p=0.015). Furthermore, ghrelin levels were positively correlated with methylphenidate dosage (p=0.024), and negatively correlated with methylphenidate side effects (p=0.044) in the ADHD+MPH group. These findings provide further insight into the relationships between appetite hormones, pharmacotherapy, and ADHD. Orexin A and leptin are associated with the etiology of ADHD, while orexin A and ghrelin play important roles in attention deficits and methylphenidate usage in ADHD.
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BACKGROUND: Poor oral intake (POI) among medical-surgical inpatients can cause malnutrition and delay recovery due to medical consequences and the need for more invasive nutritional support. Many psychiatric conditions can cause POI; however, the role that psychiatric conditions play in POI has received limited attention to date. OBJECTIVE: This review aggregates available information on POI due to psychiatric conditions and provides a framework for the clinical approach to these conditions in hospitalized adult patients. METHODS: We searched PubMed and EMBASE for reviews of POI due to psychiatric causes, but no relevant publications were identified. Diagnostic criteria for relevant conditions in the DSM-5-TR and Rome IV were reviewed, as were C-L psychiatry textbooks and relevant society websites. This review was further supplemented by a case conference at the authors' institution. RESULTS: We have divided results into five sections for clinical utility: (1) the need to rule out medical and psychotropic causes of POI; (2) unpleasant somatic experiences causing POI; (3) mood, psychotic, catatonic, and neurocognitive disorders that can present with POI; (4) eating and feeding disorders; and (5) personal and interpersonal explanations of POI. Within each section, we review how to identify and manage each condition, specifically considering effects of treatment on oral intake. CONCLUSIONS: The clinical management of POI varies based on cause. For instance, psychostimulants can cause POI due to inappetence; however, they can treat POI due to abulia by improving motivation. The fact that such a broad range of psychiatric conditions can cause POI calls for a systematic clinical approach that considers the categories of potential causes. We also identified a need for prospective studies focused on the management of POI due to psychiatric conditions, as the literature on this topic is limited to case reports, case series, and retrospective cohort studies.
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The war in Ukraine has exposed children to extremely high levels of acute and chronic stressors, which can impact their eating behaviour (EB). We aimed to determine the prevalence of war-induced, stress-related disruptions in EB of Ukrainian children. We conducted a cross-sectional online survey among parents of 5- to 17-year-old children, who had experienced the war in Ukraine in February-May 2023. Guardians reported their child's various war exposure changes in EBs using a modified version of the Child Eating Behaviour Questionnaire. We assessed associations between total and medium-term EB changes and age, sex, and war exposure using bivariate correlations and χ2 tests. Logistic regression models were fitted to explore the associations between socio-demographic factors, war exposure and frequency of EB changes. Of the 4854 children, 63% had changes in EBs during the war. The most common EB changes included food cravings (38%), food fussiness (37%), and aversion to certain foods (29%). Of the reported EB changes, 40% were medium-term, lasting over a month, and related to altered attitudes towards food. Food insecurity (adjusted OR 2.35, 95% CI: 1.76-3.14), and displacement (internally 2.01, 1.19-3.42) emerged as the most influential determinants of medium-term EB changes. The findings underscore a significant and robust association between war-related exposures and an increased risk of frequent EB changes. As healthy EBs are learned during childhood and have been shown to track into adulthood, the identified disruptions in EB may have medium-term consequences for the physical and mental health of Ukrainian children.
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Objectives: This study aimed to investigate the association between internet addiction and dietary habits among Omani junior college students. Methods: This cross-sectional study was conducted at Sultan Qaboos University, Muscat, Oman, among junior college students surveyed in November 2020. The Compulsive Internet Use Scale and a dietary habits questionnaire were used. Chi-square cross-tabulation analyses were used to explore the relationship between internet addiction and dietary habits. Results: A total of 377 students were included in this study. Overall, 59.9% of the junior college students were identified as having an internet addiction. Within this group, 62.8% reported reduced meal sizes and 54.4% reported a decrease in appetite. There was a statistically significant difference in both meal size (X2 = 30.528; P <0.001) and appetite changes (X2 = 28.731; P <0.001) among students with different levels of internet addiction. Conclusion: The results of this study suggest a possible link between internet addiction and altered dietary habits among this population. This study highlights the need for strategies that encourage healthy living behaviours and raise awareness about the adverse effects of internet addiction.
Subject(s)
Feeding Behavior , Internet Addiction Disorder , Students , Humans , Oman/epidemiology , Cross-Sectional Studies , Male , Female , Students/statistics & numerical data , Students/psychology , Feeding Behavior/psychology , Internet Addiction Disorder/epidemiology , Internet Addiction Disorder/psychology , Adolescent , Surveys and Questionnaires , Young Adult , Universities/statistics & numerical data , Internet/statistics & numerical data , Behavior, Addictive/epidemiology , Behavior, Addictive/psychologyABSTRACT
(1) Background: We examined the effect of the acute administration of olive oil (EVOO), linseed oil (GLO), soybean oil (SO), and palm oil (PO) on gastric motility and appetite in rats. (2) Methods: We assessed food intake, gastric retention (GR), and gene expression in all groups. (3) Results: Both EVOO and GLO were found to enhance the rate of stomach retention, leading to a decrease in hunger. On the other hand, the reduction in food intake caused by SO was accompanied by delayed effects on stomach retention. PO caused an alteration in the mRNA expression of NPY, POMC, and CART. Although PO increased stomach retention after 180 min, it did not affect food intake. It was subsequently verified that the absence of an autonomic reaction did not nullify the influence of EVOO in reducing food consumption. Moreover, in the absence of parasympathetic responses, animals that received PO exhibited a significant decrease in food consumption, probably mediated by lower NPY expression. (4) Conclusions: This study discovered that different oils induce various effects on parameters related to food consumption. Specifically, EVOO reduces food consumption primarily through its impact on the gastrointestinal tract, making it a recommended adjunct for weight loss. Conversely, the intake of PO limits food consumption in the absence of an autonomic reaction, but it is not advised due to its contribution to the development of cardiometabolic disorders.
Subject(s)
Appetite Regulation , Hypothalamus , Neuropeptide Y , Olive Oil , Palm Oil , Soybean Oil , Vagus Nerve , Animals , Vagus Nerve/drug effects , Vagus Nerve/physiology , Hypothalamus/metabolism , Hypothalamus/drug effects , Male , Olive Oil/pharmacology , Neuropeptide Y/genetics , Neuropeptide Y/metabolism , Palm Oil/pharmacology , Appetite Regulation/drug effects , Soybean Oil/administration & dosage , Soybean Oil/pharmacology , Rats, Wistar , Linseed Oil/pharmacology , Rats , Eating/drug effects , Plant Oils/pharmacology , Pro-Opiomelanocortin/genetics , Pro-Opiomelanocortin/metabolism , Nerve Tissue Proteins/genetics , Nerve Tissue Proteins/metabolism , Gastrointestinal Motility/drug effects , Gene Expression Regulation/drug effects , RNA, Messenger/metabolism , RNA, Messenger/geneticsABSTRACT
Malnutrition is a significant concern affecting the elderly, necessitating a complex assessment. This study aims to deepen the understanding of factors associated with the assessment of malnutrition in the elderly by comparing single- and multi-parameter approaches. In this cross-sectional study, 154 individuals underwent a comprehensive geriatric assessment (CGA). Malnutrition risk was determined using the mini nutritional assessment (MNA). Additional factors assessed included sarcopenia, polypharmacy, depression, appetite, handgrip strength, and gait speed. Phase angle (PA) and body composition were measured using bioelectrical impedance analysis (BIA). The MNA identified a malnutrition risk in 36.8% of individuals. The geriatric depression scale (GDS) and PA demonstrated moderate effectiveness in assessing malnutrition risk, with AUC values of 0.69 (95% CI: 0.60-0.78) and 0.62 (95% CI: 0.54-0.72), respectively. A logistic regression model incorporating handgrip strength, skeletal muscle mass, sarcopenia, osteoporosis, depression, specific antidepressant use, mobility, appetite, and smoking achieved superior performance in predicting malnutrition risk, with an AUC of 0.84 (95% CI: 0.77-0.91). In conclusion, this study demonstrates that integrating multiple parameters into a composite model provides a more accurate and comprehensive assessment of malnutrition risk in elderly adults.
Subject(s)
Geriatric Assessment , Hand Strength , Malnutrition , Nutrition Assessment , Humans , Aged , Malnutrition/epidemiology , Malnutrition/diagnosis , Female , Male , Geriatric Assessment/methods , Cross-Sectional Studies , Aged, 80 and over , Risk Factors , Body Composition , Depression/epidemiology , Risk Assessment , Sarcopenia/epidemiology , Sarcopenia/diagnosis , Nutritional Status , Electric Impedance , Appetite , Logistic ModelsABSTRACT
Obesity is a chronic disease caused primarily by the imbalance between the amount of calories supplied to the body and energy expenditure. Not only does it deteriorate the quality of life, but most importantly it increases the risk of cardiovascular diseases and the development of type 2 diabetes mellitus, leading to reduced life expectancy. In this review, we would like to present the molecular pathomechanisms underlying obesity, which constitute the target points for the action of anti-obesity medications. These include the central nervous system, brain-gut-microbiome axis, gastrointestinal motility, and energy expenditure. A significant part of this article is dedicated to incretin-based drugs such as GLP-1 receptor agonists (e.g., liraglutide and semaglutide), as well as the brand new dual GLP-1 and GIP receptor agonist tirzepatide, all of which have become "block-buster" drugs due to their effectiveness in reducing body weight and beneficial effects on the patient's metabolic profile. Finally, this review article highlights newly designed molecules with the potential for future obesity management that are the subject of ongoing clinical trials.
Subject(s)
Anti-Obesity Agents , Obesity , Humans , Obesity/drug therapy , Obesity/metabolism , Anti-Obesity Agents/therapeutic use , Anti-Obesity Agents/pharmacology , Animals , Energy Metabolism/drug effects , Glucagon-Like Peptide-1 Receptor/agonists , Glucagon-Like Peptide-1 Receptor/metabolism , Diabetes Mellitus, Type 2/drug therapy , Diabetes Mellitus, Type 2/metabolism , Gastrointestinal Microbiome/drug effectsABSTRACT
Eating behaviour and circadian rhythms are closely related. The type, timing, and quantity of food consumed, and host circadian rhythms, directly influence the intestinal microbiota, which in turn impacts host circadian rhythms and regulates food intake beyond homeostatic eating. This Opinion discusses the impact of food intake and circadian disruptions induced by an obesogenic environment on gut-brain axis signalling. We also explore potential mechanisms underlying the effects of altered gut microbiota on food intake behaviour and circadian rhythmicity. Understanding the crosstalk between gut microbiota, circadian rhythms, and unhealthy eating behaviour is crucial to addressing the obesity epidemic, which remains one of the biggest societal challenges of our time.
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While an intensity-dependent post-exercise decrease in energy intake (EI) has been described in adolescents with obesity, studies invariably used ad libitum meals, limiting then any conclusions regarding the effect of exercise on post-meal appetitive responses that can be also impacted by the ad libitum nature of the meal. This study analyses appetite and food-reward related responses to a fixed meal after an acute exercise, also exploring the associations between substrate use during exercise and overall daily EI in adolescents with obesity. Thirteen adolescents with obesity (12-16 years, 5 males) randomly complete 2 experimental sessions: (i) a control condition (CON); (ii) a 30-min moderate intensity (65% VO2peak) cycling condition (EX). Energy expenditure and substrate oxidation were measured during both 30 min of rest (CON) or exercise (EX). Ad libitum EI, macronutrient intake and relative EI were assessed at dinner, subjective appetite sensations taken at regular intervals and food reward measured before and after lunch as well as before dinner. Energy and macronutrient intake did not differ between conditions, as well as appetite feelings. A time effect (p = 0.012) was observed between pre and post meal for choice fat bias in both conditions but was only significant within the CON condition (p = 0.004). CHO oxidation during exercise was found correlated with both EI (r = 0.586, p = 0.045), pre-lunch hunger (r = 0.624, p = 0.030), daily AUC for hunger and DTE (r = 0.788, p = 0.002 and r = 0.695; p = 0.012 respectively). This exploratory study highlights that acute exercise might not affect subsequent appetite responses when using a fixed test meal in adolescents with obesity.
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Objective: Co-treatment with long acting PYY and the GLP-1 receptor agonists has potential as an efficient obesity treatment. This study investigates whether the mechanisms behind additive reduction of food intake and weight loss depends on complementary effects in brain areas regulating food intake and if restoration of leptin sensitivity is involved. Methods: Diet-induced obese (DIO) mice were co-treated with PYY(3-36) and exendin-4 (Ex4, GLP-1R agonist) for 14 days using minipumps. Leptin responsiveness was evaluated by measuring food intake and body weight after leptin injection, and gene expression profile was investigated in various of brain regions and liver. Results: We show that weight loss associated with co-treatment of PYY(3-36) and Ex4 and Ex4 mono-treatment in DIO mice increased expression of several genes in area postrema (AP) known to be involved in appetite regulation and Cart, Pdyn, Bdnf and Klb were synergistically upregulated by the co-treatment. The upregulations were independent of weight loss, as shown by inclusion of a weight matched control. Moreover, PYY(3-36) and Ex4 co-treatment resulted in synergistically upregulated plasma concentrations of soluble leptin receptor (SLR) and improved sensitivity to exogenous leptin demonstrated by food intake lowering. Conclusion: The study results suggest that synergistic upregulation of appetite-regulating genes in AP and improved leptin sensitivity are important mediators for the additive weight loss resulting from PYY and Ex4 co-treatment.
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Background and Objective: Research has linked marijuana use with lower body mass index (BMI). The current study explores the correlation between marijuana use on BMI in the general U.S. population. It reports the prevalence of marijuana in adults in relation to BMI, overall and across the levels of important variables. Materials and Methods: This study used a probability sample of U.S. adults 18 years of age and older from the 2016 through 2022 Behavioral Risk Factor Surveillance System, a telephone-administered survey. The survey collects data from a representative sample regarding health-related risk behaviors, chronic health conditions, and use of preventive services. The primary outcome variables are current (at least once in the last 30 days) and daily (at least 20 of the last 30 days) marijuana use. Results: The study sample consists of 735,921 participants in the surveys that completed the optional module on marijuana use. Prevalence of marijuana use in adults doubled during the study period (7.48% to 14.91%). The increase directly corresponds with a shift toward legalization of medical and recreational marijuana. On average, the prevalence of use is 9% higher when medical marijuana is legal and 81% higher when recreational marijuana is legal (vs. not legal). For obese individuals, prevalence of current marijuana use is 35% lower than for nonobese individuals on average. Lower prevalence of marijuana use in obese individuals is consistently observed across the levels of certain demographic variables, employment status, tobacco smoking history, marijuana legalization status, and certain medical conditions (asthma, arthritis, and depression). In 2022, the adjusted odds of current or daily marijuana use are significantly lower and similar among obese (vs. non-obese) (0.68, 0.69, respectively), such that reduced obesity does not require daily use. Similarly, the adjusted odds of current marijuana use decrease in similar fashion to daily marijuana use with higher BMI weight classification. Conclusion: Marijuana use is correlated with lower BMI. As legalization and prevalence of the drug in the U.S. increases, the prevalence of obesity may decline. However, clinicians should view this outcome along with the known health risks associated with marijuana use.
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The mechanism connecting gut microbiota to appetite regulation is not yet fully understood. This study identifies specific microbial community and metabolites that may influence appetite regulation. In the initial phase of the study, mice were administered a broad-spectrum antibiotic cocktail (ABX) for 10 days. The treatment significantly reduced gut microbes and disrupted the metabolism of arginine and tryptophan. Consequently, ABX-treated mice demonstrated a notable reduction in feed consumption. The hypothalamic expression levels of CART and POMC, two key anorexigenic factors, were significantly increased, while orexigenic factors, such as NPY and AGRP, were decreased. Notably, the levels of appetite-suppressing hormone cholecystokinin in the blood were significantly elevated. In the second phase, control mice were maintained, while the ABX-treated mice received saline, probiotics, and short-chain fatty acids (SCFAs) for an additional 10 days to restore their gut microbiota. The microbiota reconstructed by probiotic and SCFA treatments were quite similar, while microbiota of the naturally recovering mice demonstrated greater resemblance to that of the control mice. Notably, the abundance of Akkermansia and Bacteroides genera significantly increased in the reconstructed microbiota. Moreover, microbiota reconstruction corrected the disrupted arginine and tryptophan metabolism and the abnormal peripheral hormone levels caused by ABX treatment. Among the groups, SCFA-treated mice had the highest feed intake and NPY expression. Our findings indicate that gut microbes, especially Akkermansia, regulate arginine and tryptophan metabolism, thereby influencing appetite through the microbe-gut-brain axis.
Subject(s)
Gastrointestinal Microbiome , Metabolome , Animals , Gastrointestinal Microbiome/drug effects , Mice , Male , Mice, Inbred C57BL , Anti-Bacterial Agents/pharmacology , Tryptophan/metabolism , Appetite/drug effects , Probiotics/pharmacology , Arginine/pharmacology , Arginine/metabolism , Hypothalamus/metabolism , Appetite Regulation/physiology , Fatty Acids, Volatile/metabolismABSTRACT
Introduction: Individuals living or working at high altitudes typically experience altered taste perceptions and reduced appetite. These changes can lead to nutritional deficiencies, affecting the energy balance and body composition. Methods: We conducted a nonsystematic review of PubMed to explore these phenomena and expound on their findings to offer additional insights. Results: Changes in taste and perception are common and typically lead to loss of mass. There are limited practical solutions to mitigate these challenges. Discussion: Gradual acclimatization and tailored nutritional strategies are required to enhance health and performance in high-altitude environments. This review provides critical insights into the intersection of altitude, nutrition, and health.
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BACKGROUND: Smoking cessation is crucial for reducing complications of type 2 diabetes mellitus (T2DM), but associated weight gain can worsen glycemic control, discouraging quitting attempts. Varenicline, a partial agonist of α4ß2 nicotinic receptors, aids smoking cessation. This study examines the effects of varenicline on body weight and metabolic parameters in patients with T2DM and prediabetes. METHODS: Fifty-three patients were enrolled, of which 32 successfully quit smoking after a three-month course of varenicline and were examined after an additional month with no medication. Measurements taken at baseline, 2.5 months, and 4 months included body weight, blood pressure, resting metabolic rate (RMR), glycated hemoglobin (HbA1c), fasting glucose, blood lipids, C-reactive protein (CRP), appetite-related hormones, and physical activity. RESULTS: Post-treatment, there were no significant changes in body weight, blood pressure, RMR, or glycemic control. Total (CHOL) and low-density lipoprotein (LDL-C) cholesterol decreased significantly at 4 months of the study (from 168 to 156 mg/dL, p = 0.013, and from 96 to 83 mg/dL, p = 0.013, respectively). Leptin levels increased (from 11 to 13.8 ng/dL, p = 0.004), as did glucagon-like peptide-1 (GLP-1) levels (from 39.6 to 45.8 pM, p = 0.016) at 4 months of follow-up. The percentage of participants who reported moderate-intensity activity increased from 28% to 56%, while those reporting high-intensity activity increased from 19% to 22%, respectively (p = 0.039). CONCLUSIONS: Our study showed that smoking cessation with varenicline in smokers with T2DM and prediabetes led to significant improvements in lipid profile, significant increase in plasma leptin and GLP-1 levels, and increased physical activity, without significant weight gain. Thus, smoking cessation without weight gain or deteriorated glycemic control is feasible for these smokers, with added benefits to lipid profiles, GLP-1 regulation, and physical activity.
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BACKGROUND AND OBJECTIVES: This study aimed to evaluate the effects of milk and banana given as a bedtime snack to patients with primary insomnia on sleep parameters and some biochemical parameters such as brain-derived neurotrophic factor, leptin, and ghrelin. METHODS AND STUDY DESIGN: 21 patients with insomnia who met the inclusion criteria participated in this study. The patients were divided into 3 parallel groups: banana, milk and control. The intervention group were given either 1 portion of banana or just 200 mL of whole-fat milk at bedtime. The control group did not consume any non-routine food. Venous blood samples were taken at baseline and after the study from patients to measure brain-derived neurotrophic factor, leptin and ghrelin concentrations. Sleep quality and architecture were determined by polysomnography and Pittsburg Sleep Quality Index. RESULTS: Pittsburg Sleep Quality Index scores of the banana and milk group were found to be lower after intervention (p<0.05). In terms of polysomnography, the total sleep time of the milk group was found to be significantly higher than baseline. Serum ghrelin concentration of the milk group decreased significantly compared to baseline. CONCLUSIONS: Bedtime milk or banana intake was effective in dealing with insomnia. Foods rich in tryptophan, such as banana and milk, given at bedtime, may improve sleep parameters and appetite hormones.
Subject(s)
Leptin , Milk , Musa , Sleep Initiation and Maintenance Disorders , Sleep , Humans , Male , Female , Sleep/physiology , Animals , Leptin/blood , Adult , Middle Aged , Ghrelin/blood , PolysomnographyABSTRACT
The first systematic reviews of the effects of exercise on appetite-regulation and energy intake demonstrated changes in appetite-regulating hormones consistent with appetite suppression and decreases in subsequent relative energy intake over a decade ago. More recently, an intensity-dependent effect and several potential mechanisms were proposed, and this review aims to highlight advances in this field. While exercise-induced appetite suppression clearly involves acylated ghrelin, glucagon-like peptide-1 may also be involved, though recent evidence suggests peptide tyrosine tyrosine may not be relevant. Changes in subjective appetite perceptions and energy intake continue to be equivocal, though these results are likely due to small sample sizes and methodological inconsistencies. Of the proposed mechanisms responsible for exercise-induced appetite suppression, lactate has garnered the most support through in vitro and in vivo rodent studies as well as a growing amount of work in humans. Other potential modulators of exercise-induced appetite suppression may include sex hormones, growth-differentiation factor 15, Lac-Phe, brain-derived neurotrophic factor, and asprosin. Research should focus on the mechanisms responsible for the changes and consider these other modulators (i.e., myokines/exerkines) of appetite to improve our understanding of the role of exercise on appetite regulation.
Subject(s)
Appetite Regulation , Exercise , Humans , Exercise/physiology , Animals , Appetite Regulation/physiology , Ghrelin/metabolism , Ghrelin/blood , Appetite/physiologyABSTRACT
Appetite for Risk is an autobiographical memoir of the author's life experiences. He vividly explains near-death experiences while maintaining humor, regaling about his escapades. It is thought-provoking to consider if human risky behavior is genetically predetermined.
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Elevation of the plasma levels of (S)-lactate (Lac) and/or (R)-beta-hydroxybutyrate (BHB) occurs naturally in response to strenuous exercise and prolonged fasting, respectively, resulting in millimolar concentrations of these two metabolites. It is increasingly appreciated that Lac and BHB have wide-ranging beneficial physiological effects, suggesting that novel nutritional solutions, compatible with high-level and/or sustained consumption, which allow direct control of plasma levels of Lac and BHB, are of strong interest. In this study, we present a molecular hybrid between (S)-lactate and the BHB-precursor (R)-1,3-butanediol in the form of a simple ester referred to as LaKe. We show that LaKe can be readily prepared on the kilogram scale and undergoes rapid hydrolytic conversion under a variety of physiological conditions to release its two constituents. Oral ingestion of LaKe, in rats, resulted in dose-dependent elevation of plasma levels of Lac and BHB triggering expected physiological responses such as reduced lipolysis and elevation of the appetite-suppressing compound N-L-lactoyl-phenylalanine (Lac-Phe).