Loss of appetite means a reduced interest in eating. It can be short-lived or persistent and may stem from many causes — infections, digestive issues, chronic illnesses, medication effects or mental health concerns. This page explains likely causes, associated signs, how clinicians approach evaluation and when to contact health services. This is general information and not a substitute for professional medical assessment.
Common causes and contributing factors
Loss of appetite is a symptom with many potential origins. Common causes include acute infections, digestive tract conditions (gastritis, ulcers), chronic medical conditions, metabolic or hormonal imbalances, side effects of medications, mood disorders (depression, anxiety), stress, eating disorders and some cancers. In older adults, changes in taste and smell or dental problems can reduce appetite.
Warning signs: when to seek urgent care
Accompanying signs such as rapid, unexplained weight loss, persistent high fever, severe dehydration, intense abdominal pain, vomiting or bloody stools, or sudden changes in consciousness warrant prompt medical attention. For severe or rapidly worsening symptoms, contact emergency services or go to the nearest emergency department.
How clinicians evaluate loss of appetite
Evaluation starts with a detailed history and physical exam. Clinicians ask about onset and duration, associated symptoms, recent weight change, current medications, medical history and psychosocial factors. Initial tests may include blood work (complete blood count, electrolytes, liver and kidney tests, thyroid function), urine tests and imaging when indicated. Further tests such as endoscopy, infection screening or oncology referrals depend on the clinical picture.
Supportive measures you can try
To support nutrition while evaluating the cause, try small frequent meals, choose energy-dense and preferred foods, use nutritious beverages or oral supplements if tolerated, maintain regular mealtimes, and include light physical activity if appropriate. Addressing stress, sleep and oral health may help. Persistent appetite loss or weight loss should prompt medical review.
Which clinician to see
Start with your primary care clinician. Depending on findings you may be referred to specialties such as gastroenterology, internal medicine, psychiatry, infectious diseases or oncology for further evaluation and management.