- [Andrew] Wanna try some gummies?

- [Co-Worker] Oh gosh, no.

- [Andrew] For science?

- [Co-Worker 2] That's not good.

- [Andrew] No?

What's the flavor?

- [Co-Worker 2] Bad.

- [Andrew] Those two are pretty standard sweeteners that you'll find in just about any coffee shop.

- [Sam] Okay.

- [Andrew] These other two, you will not find anywhere, really.

'Cause they're way too sweet to be useful.

And they're also super expensive.

- [Sam] Oh wow.

Okay.

- [Andrew] Also, before you get started, for the hardcore fans.

- Hi, I'm Sam, I'm still alive.

(laughs) Is that a good greeting?

(loud ding) - A while back, some Amazon reviews of sugar-free gummies went viral because a lot of people were reporting severe gastrointestinal distress when they ate them.

Well, apparently, that is actually real.

And those gummies have been discontinued because the artificial sweetener they used, was in fact, a laxative.

Why would you put a laxative in?

Now, it seems to me, that there are three things you want out of an artificial sweetener.

One, tastes sweet.

Two, has fewer calories than sugar.

And three, doesn't cause diarrhea or other life disrupting health impacts when you eat it.

Turns out, getting all three of those things just right is more difficult than you would think.

So, I have a few artificial sweeteners that supposedly do not cause gastrointestinal distress.

I'm gonna test them out in some coffee first.

And then I'm gonna see if I can find one that works for a sugar-free gummy that won't ruin your day.

There's a lot of scientific interest around why we have evolved to like sweet things.

So much scientific interest in fact, that Sam and Deboki have dedicated an entire episode of their "Tiny Matters" podcast to it.

Link down below.

- Listen to to Tiny Matters!

- But, I don't care so much about why we like sweet things.

I'm more interested in what alternatives are available to satiate our sweet desires.

But how does something that isn't sugar trick your tongue into thinking that it is?

Well, first off, how do we even taste sugar to begin with?

(soft crunch) Mm-hm, that's sugar.

I'm not sure what I hope to learn.

Sucrose, fructose and glucose, are the big three sugars we think about when we're talking about sweet things.

When one of those hits your tongue it interacts with taste receptor cells or TRCs.

Some of these TRCs detect sweet molecules because they have proteins on their surface called taste receptors.

There are a variety of different kinds of taste receptors that can detect bitter, salty, umami.

But today, we're really just interested in the sweet taste receptors.

The sweet taste receptor is made up of two proteins, T1R2 and T1R3.

Those come together to form a heterodimer.

This heterodimer sits in the cell membrane.

So there is a part that sticks out into your mouth.

There is a transmembrane domain, that like it sounds, runs through the cell membrane.

And then there's another part inside the cell.

The outside, or extracellular part, has a little pocket on it where sugars or amino acids or proteins can bind.

The binding pocket where sugars go is called the Venus flytrap domain.

Presumably because someone thought it looked like a Venus flytrap, I guess?

I hope we have a graphic for this.

Things like sucrose, fructose, and glucose, bind to the extracellular domain of this heterodimer and set off a signal cascade that tells your brain, "Sweet thing good."

But they're not the only thing that can bind to this domain and send that signal to your brain.

So, we have options.

(cardboard tears) When you think of artificial sweeteners, you're probably thinking of the pink and blue and multicolored packets that sit next to the coffee stirrers in a cafe.

They work in slightly different ways and you're not imagining it.

They taste a little different too.

Some artificial sweeteners work just by being way, way sweeter than sugar.

So you only need a tiny amount of them to get the same sweet flavor in your coffee or your gummy bears.

A lot of these have names you might recognize.

Aspartame, acesulfame k, neotame, saccharin, sucralose, cyclamate and alitame.

I'm probably saying all of those wrong.

I have no idea.

Chicka-mate?

Chicka-matey?

Let's look at aspartame.

Aspartame is the blue stuff in your local cafe.

Aspartame binds to that same Venus flytrap module of the heterodimer, but it binds with greater affinity.

Meaning, it's holding down that sweet button harder and longer than just sucrose.

(elevator music) (button clicks) (bell dings) So, aspartame is up to 200 times sweeter than table sugar.

It's a combination of two different amino acids aspartic acid and phenylalinine.

Now, your body can break those down, so it does technically have some calories.

But, because it smashes that sweet button so much more effectively than sucrose, you use a lot less of it.

Making it a low calorie option.

And speaking of smashing that button, don't forget to smash that like and subscribe.

Aspartame.

(slurps and swishes) (soft gulp) Ah.

Yeah, that just tastes like normal.

Oh.

(smacks lips) At first it tastes like normal sugar but then there's something else afterwards.

A little bit of a bitter flavor, maybe a tiny bit metallic?

I mean, I'm still gonna finish this cup of coffee, but.

The nutrition facts on the side of the aspartame box, list it as having zero calories, which isn't strictly true.

But, at the serving size of one packet, which is one gram of this sweetener.

Which, contains only a tiny amount of actual aspartame.

You're not really getting a meaningful amount of energy out of it.

So, rounding down, basically zero calories.

But, some sweeteners can't be broken down by your body at all.

Sucralose is a great example of this.

That's the one that usually comes in yellow packets.

Or, you get it in a big brown bag if you don't want a ton of little packets lying around your kitchen.

Sucralose is made from sucrose, but the OH groups on sucrose are swapped out for CL groups.

Meaning, your body can't do a thing with it.

But just like aspartame, it binds to the extracellular domain of that sweet taste receptor with higher affinity than sugar.

(bell rings) So you use less of it.

In fact, sucralose is 300 to 1,000 times sweeter than sucrose.

Not only does it not have any calories but you also need way less of it than you would of regular sugar.

Now, sucralose is also pretty heat stable, which might make it a good option for our gummies later.

For now, I'm gonna try it out in some coffee.

And, I have no idea how much of this I'm supposed to use, 'cause it's not pre-measured in packets for me.

Stop.

Oh, whoa!

Wow.

And I think I'm just gonna want a very tiny amount of this.

Sucralose.

(quiet slurp) Sucralose tastes sweeter than aspartame to me.

That could just be the amount.

But, (smacks lips) it's a cleaner sweetness.

It tastes more like sugar.

It doesn't have that kind of, weird, bitter or metallic aftertaste, that I was getting from aspartame.

Normally, when you're shooting a video, you're supposed to sip and then spit.

And then you cut out the spit.

I'm not doing that, for some reason.

I actually like sucralose.

That has a good flavor to it.

Rounding out our coffee cart options is, the pink stuff.

Saccharin.

Saccharin is also not broken down by our bodies.

Meaning, you get zero calories from it.

And it binds with higher affinity than sucrose.

Saccharin is actually about 300 times sweeter than sucrose.

(paper rips) Saccharin was discovered when a chemist did not wash his hands after doing an experiment then noticed a sweet taste when he touched his food.

Come on man, put on some gloves.

Wash your hands.

Have a little self-respect.

This, unfortunately, is not the only example of an artificial sweetener being discovered through poor lab safety.

Aspartame was discovered when someone licked his finger to turn a page.

And cyclamate was discovered when a chemist set his cigarette down on the lab desk and then noticed a sweet taste when he took a puff later.

The American Chemical Society would like to remind you not to eat, lick, drink, or smoke any of the chemicals you're working with in a lab.

That means you, grad students.

(slurps coffee) Okay.

(smack lips) Not a fan of saccharin.

Maybe I just blew out my taste buds with that excessive dose of sucralose?

There's definitely a side flavor here.

There's something else going on that I'm not crazy about.

Three cups of coffee in and I'm doing just fine.

A relative newcomer to the coffee cart options is stevia.

Stevia usually comes in a green packet in your cafes.

Or, if you get it from a questionable internet source, it comes in a manila envelope.

Stevia is an extract of the Stevia rebaudiana, Stevia rebaudiana Bertoni plant.

Rather than being a single molecule like other sweeteners, stevia is several molecules.

All of them viosterol glycosides.

Modeling studies suggest that viosterol glycosides are binding with that same little extra cellular domain as regular sugars, and they're binding with greater affinity.

So you use less of them.

That makes them a low calorie option even though your body can get some energy out of stevia leaf extract.

- [Narrator] Stee-via is how it is said.

Not steh-via, but rather, stee-via.

(frustrated grunt) - So, stevia in our fourth cup of coffee, here.

Does that seem like a a good amount?

Whoa.

(smacks lips) I can taste that from opening the package.

That's concerning.

Stevia.

Very sweet.

And there's that, ugh.

(smacks lips) There's that stevia weirdness that, if you've ever had it, I think you're familiar with.

I guess some people like it.

It doesn't do it for me.

I'm still gonna finish this fourth cup of coffee, though.

(gulps) Ah.

When it first hits my tongue, it tastes just like normal sugar.

But then, just a second or two later, there's some other flavor in there that I don't have a word for.

And it just tastes fake.

But none of these options sound particularly distressing, or laxatives.

They're not laxatives, is what I'm trying to say here.

So, what was going on with those infamous gummy bears?

Well, that brand of gummy bears was sweetened with something called sugar alcohols.

Sugar alcohols are made by adding a hydrogen to a sugar molecule.

The fact checkers didn't love the way that I said that.

They thought it was a little misleading.

What I should have said, is that sugar alcohols have a hydroxyl group where sugars have an aldehyde.

It's not like there's a little guy taking hydrogens and sticking 'em onto sugars to make sugar alcohols.

Ugh!

Factual accuracy.

Sugar alcohols typically have about a third to a half the number of calories of regular sugar, because your body converts them to glucose more slowly than it does with sucrose.

The problem is that sugar alcohols can have a laxative effect.

Sugar alcohols can pass right through your stomach, unmodified, and get to your intestines where they are fermented by bacteria.

That fermentation causes gas, bloating sprinting to the bathroom, those kinds of problems.

The FDA requires products that contain a daily dose of over 50 grams of sorbitol or 20 grams of mannitol to be labeled with a "laxative effect" warning.

Sugar alcohols in and of themselves aren't necessarily bad.

But, if you eat too many gummy bears, you can exceed that laxative limit.

If you stuck to the recommended serving size of those sugar free gummies you would probably be just fine.

But who has ever stuck to the recommended serving size of gummies?

Serving size, five pieces.

Right.

And, on top of our total lack of self-control, sugar substitutes have been linked to overeating.

In flies and rats, diets rich in artificial sweeteners have caused the brain to forget that link between sweetness and calories, leading to overeating.

The link is less clear in humans, but habitual use of artificial sweeteners has been counterintuitively linked to weight gain.

It's possible that it's breaking that same link in your brain between sweetness and calories.

Causing you to eat more gummies, drink more coffee, drink more soda, and eventually, have some bad side effects.

For our sugar-free gummies, I'm thinking sucralose is gonna be the best option.

But, there are a couple other surprise contenders that I wanna throw into the mix.

The first of the surprise options is a plant protein called thaumatin.

Thaumatin is 30,000 to 100,000 times sweeter than sugar, depending on which source you believe.

And interestingly, it binds to a different spot on that heterodimer than all of the other sweeteners we've talked about so far.

Thaumatin binds to a little region called the cysteine-rich domain.

Called that because it is rich in the amino acid cysteine.

That region sits between the Venus flytrap and the transmembrane domains.

It's not totally clear why binding there causes it to be so much sweeter than sugar.

But, because it has such a strong effect, it can be used as a flavor enhancer or to mask bitter or metallic flavors from other artificial sweeteners, like saccharin.

One source suggests that the electrical charge on the outside of the protein causes it to bind to both the receptor and to other flavor molecules that might be in your mouth.

As a protein, it can be broken down by your body and generate calories.

But, because it's so sweet you only need to use a tiny, tiny bit of it.

So it doesn't have a significant caloric impact.

In fact, this little jar contains 100 milligrams of thaumatin, and costs $75.

So, that's pretty much our whole video budget, right there.

Our other surprise contender for the sugar free gummies is one called neotame, which according to some sources is the sweetest sweetener of them all.

In fact, one of the Amazon reviews I saw for this was someone who was angry that it was too sweet.

Another one suggested just dipping the tip of a knitting needle into it to get the right amount for an entire recipe.

Neotame is a derivative of aspartame and is tens of thousands of times sweeter than sugar.

In fact, I'm a little bit nervous to open this package because it might make my entire kitchen taste sweet for several weeks.

I don't know.

But, let's try making some gummies.

(inquisitive pop music plays) (metallic scraping) So here's what $75 worth of thaumatin looks like.

Can you see it down there?

Right there at the bottom, $75 bucks.

(music continues) Taking the first batch outta the mold and they actually look like gummy bears.

I can't believe I actually did something.

Now that we're far enough into this video I feel comfortable admitting to you, I don't really like gummy bears.

And I hate the taste of artificial sweetener.

So I'm gonna walk around ACS headquarters and see if I can get other people to taste test this for me.

- I hate gummies.

(Andrew laughs) It's got a good flavor.

Not too sweet, but a little sweet.

So this is the neotame.

That's kinda tasty.

Sucralose.

Ugh.

- There's no like, clearly visible cringing.

Oh wait, I spoke too soon.

(Andrew laughs) - It hit me like a little bit later.

Not right away.

Yeah, it tastes a little bit more like Diet Coke.

- [Andrew] There's like, probably close to 50 grams worth of saccharin powder in there.

The sucralose, I think I put like 30 to 40 grams of that in there.

This one probably has maybe one gram, maybe half a gram.

- [Sam] Oh my gosh.

- [Andrew] And that one has about 50 milligrams.

- [Sam] This one is saccharin?

It's very bad.

(Andrew laughs) It's very bad.

I don't wanna say rancid, but I wanna say rancid.

The neotame was very sweet to me.

- [Matt] The first two, they were tasty, right?

The sucralose was bad tasting.

- [Andrew] (laughs) Okay.

- [Matt] And the saccharin was just sort of bland.

- [Sam] I thought these two were the most like, artificial.

- [Andrew] In the end everyone agreed that two were pretty good and one was terrible.

But, no one agreed on which one was which.

- [Sam] Who put this in there?

- [Andrew] They're both food safe.

- [Sam] Yeah, yeah.

I mean, I was hoping they were food safe before you asked me.

- [Andrew] I appreciate that you didn't ask before trying them.

- That's true.

I trust you too much, Andrew.

- [Andrew] But as far as I know, no one had any explosive trips to the bathroom after eating these.

So I'm calling it a success.