Food-poisoning symptoms can begin hours or days after contaminated food, sometimes later. Vomiting after a meal therefore does not prove that meal was responsible without appropriate assessment or investigation. Preventing dehydration comes first: take frequent small sips if nausea makes drinking difficult, and seek advice if problems persist. Continue breastfeeding; do not dilute formula beyond its usual concentration. Inability to retain fluids or bloody diarrhoea needs urgent assessment. Vomiting blood, sudden severe pain or confusion requires emergency care. Prevention involves cooking, safe storage, hand hygiene and observing use-by dates, not guessing from symptoms alone.