2: Sugar Makes Kids Hyper

Grandparents are known for indulging their grandchildren, and this often includes giving them sugar-filled treats like candy, ice cream and cookies. Many parents have been frustrated when their children, after a day with grandma, refuse to sleep at night and run wild through the house. All that sugar must be the cause of this hyper behavior, right? Nope.

In December 2008, two doctors from the Indiana University of Medicine explained that out of 12 different studies, "none, not even studies looking specifically at children with attention-deficit/hyperactivity disorder, could detect any differences in behavior between the children who had sugar and those who did not" [source: British Medical Journal]. In a 1994 article published in the Journal of Abnormal Child Psychology, researchers discovered that some of the supposed increase in hyperactive behavior comes from a parent's expectations. They found that the mothers who think that their children have consumed a sugary drink will label the child's behavior as hyperactive, even if they have actually been given sugar-free soda.

Obviously, it's not good for children to eat a lot of sugar even if it doesn't cause hyperactive behavior -- it can lead to cavities and childhood obesity. So why do children seem more hyper after eating sugar? Maybe it's because they tend to eat more sugar around holidays or after a day at grandma's, which are breaks in their normal routine and generally involve a lot of playtime and excitement. If they drink a lot of soda, the caffeine may be to blame instead of the sugar.

Our final old wives' tale is about a rather sensitive subject, but we have no doubt that you've heard this one.