What should you know about flu and loss of appetite?

Loss of appetite means food feels less appealing or you feel full sooner than usual. Flu may cause this through fever, body aches, tiredness, nausea, a blocked nose or reduced taste and smell. A short period of eating less can happen during an infection, but appetite loss is not specific to flu. Gastroenteritis, gastritis, peptic ulcer, hepatitis A, depression and other conditions can also affect eating. COVID-19 may overlap with flu-like symptoms, so the whole pattern and local testing advice matter.

Take frequent sips of water, oral rehydration fluid or another suitable drink. Try small portions of soft foods such as soup, yoghurt, porridge, rice or toast, and eat when you can rather than forcing a large meal. Avoid alcohol and foods that worsen nausea. Monitor urination, mouth dryness and dizziness as clues that you may need more fluid. If you have diabetes, are pregnant, or have kidney or heart disease, ask a clinician how to manage fluids and medicines during illness.

Get urgent help for confusion, fainting, severe breathing difficulty, inability to keep fluids down, very little urine or severe weakness. Arrange medical advice when appetite loss persists after the infection improves, weight is falling without trying, abdominal pain is significant, or vomiting, yellowing of the skin or blood in vomit or stool occurs. A clinician can check hydration and consider causes beyond flu.

How can I manage food and fluids with my existing conditions or medicines? Do my nausea, abdominal symptoms or appetite changes suggest another cause? Should I test for flu or COVID-19, and when should I return if eating remains difficult?