Banana. Snack on a slice of this peel-and-eat fruit if your nausea is accompanied by dehydration or if you have been vomiting. Bananas can help replenish potassium, which is frequently lost by diarrhea and vomiting. They also provide nutrients for healthy hair, skin, and nails. Bananas are the only food that contains all 10 essential amino acids that your body cannot make itself. This means that eating bananas can help if you are suffering from protein malnutrition. A single banana has about 2% of your daily value of protein. You should avoid eating foods with seeds (such as sunflower seeds) or skins (like grapes) because they contain toxic chemicals that can irritate your stomach. However, most fruits are safe to eat when you are sick. It's best to avoid eating sand or gravel since these items can block your digestive system's tracks. Eating when you're not really hungry can cause you to consume more calories than you need. If you are already feeling full, then you did not need to eat anything. Just like any other time you want to lose weight, skipping meals is not the answer either. The best way to manage your weight while you are sick is by focusing on your appetite. If you feel like eating something, then eat something. If you do not feel like eating, then don't eat anything.