When my oldest was born, the hospital gave him a bottle of sweetened water to tide him over until the scheduled mommy feeding time. He went bananas kicking and screaming and waving his little arms around until he worn himself out and fell asleep. The doctor started running tests to see what the problem was but nothing could be found. Since I breast fed him for the first few months with plain water in between feedings, the problem seemed to disappear but as soon as I put him on a bottle/baby food he got hyper again. Doctor told me that blond/blue eyed boys were particularly sensitive to both sugar (in all it's forms) and food additives but that they usually grew out of it. Luckily, he grew out of it by the time he started school. Nice end result is that to this day, he rarely eats sweets since his 'treats' when he was young were home dried fruits.
My son is now 6 and actually looks at the labels on foods, drinks, etc. He is blond with blue eyes too.