Caffeine and kids is not a good combination; in fact, it sounds like a parent's worst nightmare. Children's energy levels are a constant source of parental dismay, yet nearly three out of four children and young adults consume caffeine every day.

Unfortunately, we don't know very much about the long-term effects of caffeine on kids' growing bodies and developing nervous systems. But to be on the safe side, the American Academy of Pediatrics (AAP) recommends against its use in children.

The Food and Drug Administration is currently investigating the safety of caffeine-containing foods and beverages, especially in children and teens. Recently, researchers from the Centers for Disease Control and Prevention (CDC) reviewed trends in kids' caffeine consumption over the past decade.

Sixty-three percent of children aged 2 to 5 consume caffeine-containing beverages on a daily basis.

Caffeine consumption among children and young adults aged 2 to 22 remained roughly the same over the years from 2000 to 2010, but the sources of caffeine changed. Children and teens are drinking fewer sodas, and while that may seem like good news, there is a hitch. Heavy-hitting caffeine beverages like coffee and energy drinks now represent a greater proportion of caffeine intake.

Sodas are still the primary source of caffeine (38 percent), but less than it was a decade ago (62 percent). Kids are now getting about 24 percent of their caffeine from coffee, up from 10 percent in 2000. Even preschoolers consume the equivalent of a half a can of soda per day, though that is actually somewhat improved since 2000.

Perhaps most worrisome is that 6 percent of kids’ caffeine intake comes from energy drinks, products that weren’t even available 10 years ago. Tea remains the number two source of caffeine.

The fact that 76 percent of young people between the ages of 17 to 22 consume caffeine every day may not be all that surprising. But consider this: among children 2 to 11 years old, 69 percent consume caffeine every day, and 63 percent of preschoolers (age 2 to 5) consume caffeine-containing beverages on a daily basis.

According to the FDA, moderate amounts of caffeine are not harmful in adults, and some research finds it can have some health benefits. On average, adults in the US consume about 300 mg of caffeine a day, the equivalent of three to four cups of coffee. While that is considered moderate, the effect of caffeine on a person varies with their gender, their size, and their sensitivity to caffeine.

When it comes to children, there are many unanswered questions as to the effects of caffeine intake; for example, how much is too much? The data just don’t exist.

The AAP believes caffeine has no place in the diets of children or teens. Its potential side effects include a rapid heartbeat, high blood pressure, worsening anxiety in those with anxiety disorders, as well as sleeplessness and all the negative behavior and health effects associated with too little sleep.

The CDC report, published online in the journal Pediatrics, will serve as a baseline for future research to monitor trends in kids’ caffeine intake. Researchers expressed concern that caffeine intake may be increasing among children and teens due to the growing popularity of energy drinks and coffee beverages.

Parents should make a point of limiting their children's access to caffeine, particularly if their children are having trouble getting enough sleep. Older children should be educated about the possible problems it can cause, particularly in the heavy doses found in energy drinks.

While no one is asking parents to give up their morning coffee, keeping energy drinks and soda out of the house can only help reduce caffeine consumption — and behavior problems — in their children.