Medical specialists in Brazil have raised concerns regarding the growing use of injectable weight-loss medications based on GLP-1 receptor agonists, highlighting potential mental health risks associated with excessive appetite suppression. Although these treatments have become widely adopted for obesity management, clinicians are increasingly observing behavioural and psychological changes in certain patients undergoing therapy.
GLP-1-based medications are designed to regulate blood sugar levels and reduce hunger sensations, contributing to gradual weight reduction. However, healthcare professionals have reported that in some cases, appetite suppression becomes so pronounced that individuals consume extremely limited amounts of food, resulting in rapid weight loss and emerging emotional or behavioural symptoms.
Understanding the Concept of “Agonorexia”
The informal term “agonorexia” has recently been used by clinicians to describe the extreme reduction of hunger linked to pharmacological appetite control. Unlike anorexia nervosa — a recognised psychiatric disorder characterised by an intense fear of gaining weight and distorted body image — agonorexia is not considered a formal medical diagnosis. Instead, it typically originates as a side effect of medication.
Nevertheless, experts caution that when reduced food intake becomes severe and weight loss begins to dominate a person’s daily life, the consequences may extend beyond metabolic changes and begin affecting mental wellbeing.
According to psychiatrist Lenon Mazetto, the primary concern arises when physical transformation begins influencing personal identity and behaviour. Rapid body changes, he explains, can alter self-perception and may trigger anxiety, insecurity, or fear of regaining weight. Some patients may even develop apprehension towards the return of normal appetite levels.
Mazetto also notes that the sensation of controlling hunger can function as a powerful psychological reinforcement, particularly in individuals with pre-existing emotional vulnerabilities. In certain circumstances, this behavioural pattern may increase susceptibility to clinically recognised eating disorders such as anorexia nervosa or bulimia, particularly among individuals with specific risk characteristics.
Among the risk factors identified by specialists are previous eating disorders, rigid or perfectionist personality traits, extreme “all-or-nothing” thinking patterns, and difficulty regulating emotions. Warning signs include persistent body comparison, disproportionate fear of minimal weight gain, emotional distress related to eating, and reliance on medication as a mechanism for emotional control.
Nutritional Restriction and Brain Function
From a physiological perspective, Brazilian nutrition specialist Tatiane Matos Lourenço explains that severe caloric restriction may directly influence brain performance and emotional regulation. When energy intake falls significantly below physiological requirements, the body may activate stress-related metabolic responses.
Scientific evidence in nutritional psychiatry suggests that prolonged calorie deficit may elevate cortisol levels, a hormone linked to stress responses. Elevated cortisol has been associated with increased anxiety, sleep disturbances, and greater emotional instability.
Adequate nutrient intake is also essential for neurotransmitter production, which plays a central role in mood stability and cognitive function. Reduced protein consumption or excessive carbohydrate restriction may limit the availability of amino acids necessary for neurotransmitter synthesis. Additionally, deficiencies in micronutrients such as vitamin B6, vitamin B12, iron, and magnesium have been linked in clinical research to reduced energy levels, impaired concentration, and mood alterations.
Common symptoms associated with severe dietary restriction may include irritability, mental fatigue caused by reduced glucose availability to the brain, and diminished cognitive performance.
Importance of Multidisciplinary Monitoring
Health specialists emphasise that GLP-1 weight-loss injections remain valuable therapeutic tools in obesity treatment when used under medical supervision. Clinical studies have demonstrated their effectiveness in promoting weight reduction and improving metabolic health markers.
However, experts stress that treatment must include comprehensive monitoring to ensure balanced nutrition and psychological wellbeing. Maintaining adequate protein intake, preserving lean body mass, ensuring sufficient micronutrient consumption, and establishing structured eating patterns are considered essential protective measures.
Brazilian clinicians increasingly highlight that when appetite suppression begins to influence emotional stability, self-esteem, or overall quality of life, reassessment of treatment protocols may be necessary. Medical professionals advocate for a multidisciplinary approach involving physicians, psychiatrists, and nutritionists to safeguard both physical and mental health outcomes.
As pharmacological weight management continues to expand globally, healthcare researchers emphasise that sustainable obesity treatment requires careful evaluation of both metabolic benefits and psychological safety to ensure holistic patient care.