By adjusting your diet you can improve leptin levels. Cut back on refined, processed, and fast foods. Examples are; high-glycemic-index foods are starchy foods such as white bread, potatoes, white rice and sugars. Eat more (relatively) low glycemic foods such as vegetables, fruits, lean meat, beans, and nuts.
Common symptoms of food poisoning include: 1  diarrhea. 2  nausea. 3  vomiting. abdominal cramps.  fever.
Food allergies can cause vomiting in children, as well as other symptoms, such as a raised, red, itchy skin rash (urticaria) and swelling of the face, around the eyes, lips, tongue or the roof of the mouth.