I have reactive hypoglycemia due to hereditary factors. It is very difficult to deal with, but I have been very successful for the last 2 and a half years in controlling it.
If you are tired, cranky, have mood-swings, cold-sweats, nausea, trembling, blurred vision, feelings of weakness or even panic, you may very well be suffering from it as well. I personally get very physically cold to the touch and incredibly sleepy after I eat sweets or anything with white flour. Reactive Hypoglycemia is nearly impossible to test for. However, if you eliminate all refined sugar - this includes sugar, corn syrup, honey, fructose, sucrose, white rice, white flour, white bread etc., and substitute whole grains, brown rice, and sucralose, sorbitol and other non-nutritive sweeteners for 3 weeks your symptoms should disappear if it is hypoglycemia. This may sound terribly difficult at first, but focus on the fruits, vegetables, whole grains and lean meats. You will be rewarded with so much energy, it will amaze you. If you have reactive hypoglycemia, your body can not derive energy from these processed sugars, and goes into storage mode, depriving your body of all available blood sugar. It then does this with even healthy food or whole food that you eat as long as you continue to eat these sugars. If you are eating sugar you are effectively starving all the time regardless of what you eat with this disease. By removing sugars from your diet, your body will begin to process the food that you eat for its full nutritional value. After you reach baseline - 3 weeks or so - you can test for individual differences, such as sensitivity to honey, fruit juice, etc. I personally cannot even tolerate fruit juice, but each hypoglycemia case is unique. The best advice I have come across is figure out what your body tells you. For myself, I can generally tell if I can tolerate a sugar or new food (if I am at baseline) fairly easily. If I test a food, and the next day have gained roughly 3 pounds, it is a definite no. The food has caused my body to store all that I ate that day as fat. Not good! But if I don't gain weight, it's probably just fine. Bad sugars generally trigger cravings for more sugars as well. Sorry this is so long, but it's advice I wish I'd had all in one spot 2 years ago. Best of luck!