This is you eating a lot of peanut M&Ms after seeing stories about chocolate's unbelievable health benefits.

Carlos also just loves peanut M&Ms.

Almost every week you can open the newspaper, or turn on your favorite news website—not Vox, but other news web sites—and notice that there are stories about the purported health benefits of chocolate.

Chocolate can help you live longer, it'll make your nails shinier, it'll help you lose weight.

There are so many stories about chocolate and its health benefits and we just love to gobble them up.

But chocolate hasn't always been a media darling.

In the past, it was thought to cause acne.

No, this is just regular adult acne.

I don't drink enough water.

And this article from 1997 even called it "addictive."

At Vox, we started to ask ourselves how did chocolate become a health food?

It turns out, there's a reason behind the chocolate madness.

In 1982, Mars, which is one of the world's biggest chocolate makers, established something called the Mars Center for Cocoa Health Sciences.

And its aim was to learn more about the cocoa bean and understanding chocolate and cocoa's effects on the body.

And whether it might have any health benefits.

Vox examined the Mars sponsored research and found that out of a hundred studies we identified over the last 40 years, 98 of them had positive or favorable conclusions.

That's a pretty big number, and it made us wonder: what's so magical about chocolate that it's getting these glowing reviews?

Flae-vah-nols, they're micronutrients that are found in the cocoa bean and they're thought to have antioxidant properties.

Mars' initial focus was on the overall benefits of chocolate, but it shifted to this specific compound.

Some of these studies concluded that flavanols could boost your mood and cognitive performance, and that both cocoa powder and dark chocolate can have a "favorable effect" on cardiovascular disease risk.

Which sounds awesome, but it doesn't mean all kinds of chocolate have the same health benefits—or any health benefits at all.

Dark chocolate, milk chocolate, and cocoa beans aren't the same thing.

To understand why, we have to check out a cocoa tree near the equator.

Just kidding, this isn't borders, folks.

Cocoa or cacao beans come from these trees.

The beans are roasted and ground into what we know as cocoa powder or cocoa butter.

Dark chocolate is made mostly from cocoa butter and typically has a higher percentage of cocoa.

Milk chocolate is created from cocoa and, well, milk.

The difference is that it goes through more processing with added ingredients.

It has more fats and sugar and less cocoa—that's what makes milk chocolate so sweet.

But it's also the reason milk chocolate isn't your best bet for these flavanols.

One of the big problems with flavanols, is that when you process chocolate you end up killing them off.

In addition, different types of cocoa beans have varying amounts of flavanols to begin with.

So, different kinds of chocolate contain varying amounts of the compound manufacturers have been basing their studies on.

So, the reason companies are funding so much science, they're putting money into their own science and research institutions, and they're funding chairs at universities.

And the reason they're doing that is to sell more chocolate.

Chocolate is big business.

Chocolate sales have gone up from $14.2 billion in 2007 to $18.9 billion in 2017.

And Mars isn't the only company profiting from this.

Some of the world's biggest chocolate makers are also funding cocoa science, hyping it up to be the next big thing to help you lose weight, or remember where you left your keys.

When the media, and press offices interpret some of these studies, we like to write "chocolate" in our stories even though the studies were only looking at cocoa beans or cocoa supplements.

Despite a growing obesity epidemic, this niche of nutrition science is steering health-conscious consumers toward premium and gourmet dark chocolate.

These products are now seen as "healthy indulgences."

In short term studies, researchers have found that flavanols can lower blood pressure or improve cognition by certain measures.

But none of these things have actually been studied in long term research on endpoints that really matter for health.

Well then, do these studies even matter?

So I want to be clear, these studies aren't necessarily bad studies, many of them have passed peer-review and been published in prestigious journals.

But when you design and interpret a study there are all kinds of ways that bias can be introduced.

This study published in Nature Neuroscience is a good example of that.

In 2014, this Mars-sponsored study looked at whether cocoa flavanols could prevent cognitive decline.

The problems with this study?

It ran for only 12 weeks, involved a small number of participants, and focused on narrow outcomes that made the results unreliable.

Okay…maybe there's more hype around the benefits of chocolate than there should be.

But like what's the worst that can happen if you eat a bunch of chocolate?

A little bit of anything isn't really bad for health.

But chocolate is also filled with a lot of sugar, calories and fat.

And consuming a lot of those things would counteract any health benefits you might get from the flavanols or the antioxidants in even the best cocoa.

Right, so you probably want to eat chocolate in moderation, and not be this guy eating a bunch of it in one sitting… dude…

Are you still filming me?

...to say, lower your blood pressure because there's no excuse, er, science to back that behavior.