This popular TED Ed lesson by nutrition and brain expert Dr. Nicole Avena clearly explains (for ages 10 and up) what happens in the brain that makes us crave sugar.

In the five-minute video, you’ll get an animated explanation of brain activity when you eat sugar:

  • Special groups of cells on the tongue send sweetness signals to the brain
  • A chemical called dopamine, part of the brain’s reward system, is activated and released
  • The reward system says, “Umm, that sugar is good. Let’s have more!”
  • But here’s the thing about sugar and the brain’s dopamine response: unlike with most foods, dopamine keeps telling you to have more and more sugar
  • So, like certain drugs, sugar is definitely addictive
  • Over-activating the brain’s reward system leads to a loss of control and gets you hooked on sugary foods
  • Also, when sugar moves down into our digestive tract, it sends signals upstairs, giving you a feeling of fullness, or telling the body to produce more insulin to deal with all that sugar

But wouldn’t it be nice to have Halloween candy every week?

Well, it would be nice, although too much sugar has been linked to obesity, tooth decay, heart disease and, of course, diabetes (among other nasty things). Insulin, mentioned above, is a hormone that regulates sugar levels in the blood. Too much sugar in the blood is toxic. And problems with sugar and insulin are connected to diabetes, a serious illness that affects nearly 400 million people around the world.

Now you understand why you crave sugar. What next?

As with all TED Ed lessons, the Dig Deeper section helps.

Since understanding is the basis for positive action, after this lesson you’ll know much better what to do!

And if you liked this TED Ed lesson, take a look at other cool ones we’ve featured on Learning Liftoff.

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About The Author

Michael Solow

Michael Solow is Consulting Editor of Learning Liftoff. He has worked as a teacher, journalist, and commercial writer/creative director. Michael has also taught high school English and junior high math, gaining his teaching certification from Vassar College and a Master's degree in the Teaching of Writing and Literature from George Mason University. His writing has been published in the New York Times, the San Francisco Review of Books,, and the Hemingway Review. He is the proud dad of two grown daughters and the happy husband of an elementary school librarian.