Weight gain, loss of appetite and fatigue: what should you know?

Reduced appetite does not always lead to weight loss. Fluid retention, reduced activity, constipation, hormonal changes, medicines or changes in eating patterns can affect weight while energy falls. An infection such as influenza, COVID-19, gastroenteritis or hepatitis A may bring tiredness and appetite change. Digestive conditions including gastritis or peptic ulcer can make eating uncomfortable. Depression can alter appetite, sleep, movement and motivation. Less common but serious illnesses, including pancreatic cancer, also need consideration when symptoms persist or progress.

Keep a short record of appetite, meals, weight trend, sleep, bowel changes, nausea, pain, fever and any new medicines. The direction and timing of the changes help a clinician decide whether examination or tests are needed.

Choose small, nourishing meals and regular fluids if large meals feel difficult. Avoid skipping food for long periods, and note whether particular foods worsen nausea, pain or bloating. Gentle movement can support sleep and appetite when you feel able, but rest during an acute illness. Do not stop prescribed medicines or start supplements to change your weight without medical advice.

Arrange a medical review if the symptoms are new, persistent, worsening or affecting daily activities. Seek urgent help for severe abdominal pain, repeated vomiting, confusion, fainting, breathing difficulty, yellowing of the skin or eyes, black or bloody stools, or inability to keep fluids down.

Ask which causes fit your symptom timeline, whether your medicines could contribute, what examination or tests are appropriate, and how to maintain nutrition while appetite is low.