This is delicious.

So sweet.

In fact, I'm having a hard time stopping.

My mouth keeps telling me I need more.

That feeling of wanting more and more and more sugar takes us all the way back to our cave people ancestors!

Whats in sugar that makes it sweet?

Why things taste sweet has to do with both the chemicals in the food itself, and the way our bodies and brains respond to them.

This is white table sugar.

It's very sweet.

This kind of sugar is made from sugar cane or sugar beets.

Plants that get boiled down until all that's left are these crystals.

Sugar crystals are sucrose, made up of two simple sugars.

Glucose and fructose.

Glucose and fructose and more complex sugars like sucrose can be found in many foods.

From ones you think of as sweet, like ice cream fruit and honey to other foods you don't think of as dessert, like milk, bread, and potatoes.

Those foods have complex carbohydrates that get broken down into sugar in your body, and lots of processed foods you buy at the grocery store have sugar added in to make them taste better.

Sugar molecules taste swee because they bind to receptors on our tongues that tell our brains, hey, that's sweet.

We also have receptors for salt, sour, bitter and umami.

When your brain tastes something sweet, it releases a chemical called dopamine, known as the pleasure chemical.

Dopamine floods you with good feelings, and that helps contribute to that feeling of wanting more.

Why?

Because evolution!

A long time ago, sugar could be hard to find, but simple sugars are a quick and efficient source of energy for running and playing.

Or back in cave people days, hunting and avoiding predators, so our body's developed a response to sugar that would encourage us to look for more and then to eat a lot of it when we got the chance.

But in modern life, sugar is everywhere, so we often have to override our body's natural craving for more to avoid eating more sugar than our bodies can handle.

So maybe just this one cookie today.

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