Good day! I have a problem with sugar digestion - after eating sugar, I got the following in order: 1. Sore throat 2. Headache 3. Fatigue, weakness it feels like a season flu. The issue reproduces just with "classic" white sugar that contains in cookies, cakes, juice, fast-food, chips, cola, and so on. However, I can eat "nature" sugars with no symptoms: fruits, nuts, vegetables, sugarless chocolate, etc. I'm a 24 y.o. Male with normal weight. I have visited an endocrinologist where I have taken diabetes tests and tests say i'm not a diabetic (moreover, the doctor said it before the test after a brief look at me). I have also visited a couple of gastroenterologists, but they said me nothing, just recommended eating less sugar. Does anybody know what kind of problem can I have what can I do to heal myself?