Americans love peanut butter.

The average child will eat 1,500 peanut butter and jelly sandwiches before he or she graduates high school, according to the U.S.-based National Peanut Board.

But there is a dispute over a new peanut butter.

It is called S-T-E-E-M, or STEEM Peanut Butter. This peanut butter adds a new ingredient: caffeine.

Caffeine is a stimulant that helps people become more awake or energetic. Coffee is a popular morning drink because it has caffeine and gives people energy in the morning.

But medical experts worry about adults who rely too heavily on caffeine. Even small amounts of caffeine can be dangerous to children, says the American Academy of Pediatrics.

United States Senator Charles Schumer says he worries about the effects on children from a product never before associated with caffeine.

"To think that peanut butter, one of the snacks most closely associated with children, might have to be stored in the medicine cabinet as opposed to the kitchen cabinet should serve as a jolt to the FDA," said Schumer, a New York Democrat.

Schumer wants the U.S. Food and Drug Administration to investigate. He noted that earlier the FDA blocked plans for a caffeinated chewing gum.

STEEM, the manufacturer, said it is selling the caffeinated peanut butter "all over the world."

The manufacturer says two tablespoons has 150 mg of caffeine. A 12-ounce regular coffee has 250 mg. The product provides caffeine in an easily digestible way, the manufacturer says.

"Caffeinated foods have been sold in U.S. stores for well over a decade and are in no way a new idea," the company said, in a statement to VOA.

The company says customers tell them they want to eat the caffeinated peanut butter so they don't have to drink as much coffee or energy drinks. The company says it is not marketing the peanut butter for children.

But Schumer is not persuaded. Peanut butter has been a favorite of children for generations, he said.

Schumer continued: "Parents across the country shouldn't have to worry about a scenario in which their child might unknowingly bite into a peanut butter and jelly sandwich that contains more caffeine than two cups of coffee."

The American Academy of Pediatrics says caffeine in small amounts can help the physical performance of adults.

But the academy urges parents not to allow children to take even small amounts of caffeine. It warns of caffeine's possible negative impact on a child's heart and brain development.

The biggest sales of peanut butter, by far, are in the United States and Canada. In Europe, the average person ate only about one tablespoon per year per person in 2012, according to the Peanut Council. The largest U.S. exports of peanut butter go to Canada, Germany, Mexico and Nigeria.

Peanut butter is a food paste made from roasted peanuts. Canadian Marcellus Gilmore Edson won the first patent for peanut butter in 1884.

I'm Anna Matteo.

Bruce Alpert reported this story for VOA Learning English. Kathleen Struck was the editor.

We want to hear from you. Tell us if you ever tried peanut butter and whether you liked it or not. Share your thoughts in the Comments section or our Facebook Page.

_____________________________________________________________

sandwiches -- n. two pieces of bread with something (such as meat, peanut butter, etc.) between them.

ingredient – n. one of the things that are used to make a food, product, etc.

caffeine – n. a substance that is found especially in coffee and tea and that makes you feel more awake

stimulant – n. something that makes you more active or gives you more energy

pediatrics – n. a branch of medicine that deals with the development, care, and diseases of babies and children

scenario – n. a description of what could possibly happen

jolt – n. to cause (something or someone) to move in a quick and sudden way

digestible – adj. easy to eat and digest