Hi, Shivering and teeth chattering are both symptoms of feeling cold or experiencing a drop in body temperature. It s possible that consuming sugary foods could cause a sudden spike in blood sugar levels, which could lead to a rapid drop in blood sugar levels (hypoglycemia) later on. This can cause shivering, sweating, and chattering teeth, among other symptoms. Another possibility is that the sugary foods could have caused an allergic reaction, which can also cause shivering and chattering teeth. In some cases, a severe allergic reaction (anaphylaxis) can be life-threatening and requires immediate medical attention. If you experience these symptoms again after consuming sugary foods, it may be worth speaking with a healthcare professional to rule out any underlying health conditions. Additionally, it may be helpful to monitor your blood sugar levels regularly, especially if you have a history of diabetes or other blood sugar-related issues. If you require a personalized response, kindly use the Ask A Doctor service and post a follow-up. Take care. Hope I have answered your question. Regards, Dr. Priyanka, General & Family Physician