Hello, Short-term illnesses like common cold can cause weight loss due to diarrhea, abdominal discomfort. It happens because of loss of appetite. Nasal polyps cause altered taste and hence loss of appetite leading to weight loss. Heavy congestion causes difficulty in breathing as well as vomiting up a thick substance called mucus. Food intake is obviously reduced. A lot more calories are required for your body to breathe in enough oxygen. Hence, due to loss of appetite you get easily exhausted and weight loss too occurs. Take fluids and water adequately. Take anti diarrheal and antacids or PPIs to help reduce stomach pain. Take antiemetics if still vomiting. Avoid hot, spicy oily fried food. Take well boiled cereals like rice in small amount. You can take a little amount of boiled potato with salt. Get clinically examined for congestion, get the underlying medical condition like nasal polyp, cold, viral infection, sinusitis be treated at the earliest. Take nutritious homemade food, boiled lean meat, boiled vegetables in small amount. As you recover, you can increase the amount of intake. Get required blood tests & investigations done to rule out any liver dysfunction. Take liver tonics and digestives to improve your appetite and gain weight. Take care. Hope I have answered your question. Let me know if I can assist you further. Regards, Dr. Nupur K, General & Family Physician