a new kind of beverage took the stage.

It wasn't a new shape or a color or flavor.

No, this was diet soda and it was awesome.

With fewer calories and less sugar

diet soda promised to be

a healthier alternative to regular soda.

But, like most promises in life

that sound too good to be true, it probably is.

Can you tell the difference

between a glass of regular and diet soda?

Turns out, neither can your body

and that's where the trouble starts.

Until recently, everything we ate

contained some amount of calories.

When we ate something sweet, for example,

the brain sent signals to our pancreas,

which started producing insulin

that stored the sugar molecules in our cells for energy.

So, when we drink diet soda,

the sweetness tricks our body into thinking it's real sugar

but when those energy packed calories don't arrive

the insulin has nothing to store.

Scientists think that repeatedly tricking our body this way

could explain why study after study

keeps finding the same thing.

That drinking diet soda

is associated with metabolic syndrome.

Metabolic syndrome is a mix of conditions

that includes increased blood pressure,

high blood sugar and weight gain

which can increase the risk of diabetes,

heart disease and stroke.

In fact, one study found that diet soda drinkers

had a higher risk of stroke and dementia than regular soda drinkers.

And for another eight-year-long study, between 1979 and 1988

participants who started out at a normal weight

and drank an average of 21 diet beverages a week

faced double the risk of becoming overweight or obese by the end of the study

compared to people who avoided diet beverages completely.

And while drinking diet soda with the meal may sound like

a tasty calorie free alternative to plain water,

the growing body of research is starting to find

that this may be the worse time to drink it

because the fake calories in the diet soda

could ultimately disrupt how many

of the real calories we metabolize,

potentially leaving excess calories behind

that we then store as fat.

Another issue could be the fact

that artificial sweeteners in diet sodas

can be 10s to 100s of times sweeter than sugar.

So when we taste it, our brains anticipate

more calories than what we give it.

It's like when you go to a party expecting loads of food

and you end up with a handful of veggies and vegan cheese.

You're left unsatisfied and hangry.

In the same way, artificial sweeteners

can leave our brains wanting more

which studies have shown leads to increased appetite

and potential weight gain in fruit flies, mice, and humans.

So if the reason you're drinking diet soda

is to drop a few pounds, maybe just stick to water.

Got any friends obsessed with diet soda?

Share this video with them and thanks for watching.