cookies or cake, we like our sweet stuff.

But have you ever thought about

why you have that sweet tooth?

Turns out, it’s all about evolution.

Let’s hear more from this gentleman...

In a tie.

“The Reason is that in nature, foods

that are sweet are incredibly rare,

but they’re a great source of energy.

Sucrose is a carbohydrate. As is glucose,

fructose, etc. Carbohydrates are molecules

that contain an awful lot of energy.

So mammals, whenever they found a source of

carbohydrates, ate as much of it as they could.”

Now we’re not running away from sabretooth

tigers and walking miles for food anymore.

But what makes these foods taste,

you know, sweet?

To be sweet, a molecule has to have three

very specific chemical features that

form a triangle of just the right size.

Here is how sucrose, or table sugar,

fits into the delightfully name 'sweetness triangle.'

Scientists have different ways of

describing this interaction, but

one way is like a hand in a glove.

If the molecule in your food or drink

and the receptor on your tongue

fit together, your brain gets

an electrical impulse that says

“sweeeeet.”

“But what about artificial sweeteners?

“our diet-sipping soda viewers ask.

The granddaddy is saccharin, which was

widely used during world war one when

sugar was strictly rationed.

It’s still around today as “sweet –n– low”.

And it’s in tab. Remember tab?

By the 80s artificial sweeteners went big time

with aspartame, you’ve seen it marketed as

“nutrasweet” or “equal”, and it is almost

certainly in your favorite diet soda.

But here’s the funny thing. Aspartame doesn’t

look anything like table sugar, or sucrose.

“Now, aspartame, as a molecule,

isn’t even close to a sugar.

It’s in fact a tiny little protein.

It’s the addition of aspartic acid and

phenylalanine, known as amino acids,

this means that aspartame is chemically

more similar to meat than it is to sugar.”

So artificial sweeteners taste sweet because

they fit into the sweetness triangle.

But only part of the aspartame molecule fits.

Chemists have since created or discovered

other molecules like sucralose, and stevia,

both of which are sweeter than aspartame,

and hundreds of times sweeter than table sugar.

So that’s why things taste sweet.

Hey, you know what else would be sweet?

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