We Blind Taste Tested Diet Sodas Against Their Zero-Sugar Counterparts

I love soda but if I keep drinking multiple cans every day — and I don’t want to be dramatic here — I’ll f*cking die. Too hyperbolic? Maybe. But really, no one should be downing multiple Coca-Cola’s a day. Sorry.

The easiest way to break that habit is by supplementing your favorite full-sugar soda with its zero-sugar, zero-calorie counterpart. At least, that’s what I’m trying to do. But while navigating the no-calorie soda world I’ve been struck with a choice: Do I go for diet or zero sugar?

As a full-sugar soda drinker, I’ve always written off these options as differences in marketing. But since I’ve started looking for a substitute for Coca-Cola, I’ve realized that diet and zero-sugar sodas can taste incredibly different. Also, if these brands are willing to have different formulations of a zero-calorie sugar-free product, we’re willing to bet there are significant audiences for both.

So which resembles the real thing? We decided to put each brand’s diet and zero sugar options head to head in a blind taste test to determine which is the best from each brand.

Methodology

Diet Soda
Dane Rivera

This test is a bit different than our usual blind taste test. Rather than a big ranking, we decided to put each brand’s diet and zero-sugar formulation against one another in a two-taste head-to-head. So think of this as four mini rankings. Here are the sodas we tasted.

  • Coca-Cola Zero Sugar vs. Diet Coke
  • Dr. Pepper Zero Sugar vs Diet Dr. Pepper
  • Pepsi Zero Sugar vs Diet Pepsi
  • Mountain Dew Zero Sugar vs Diet Mountain Dew

There are a few brands out there that didn’t have both a diet and zero sugar formulation, so we eliminated those brands. We’ll do a big diet and zero-sugar soda ranking soon, for now, we’re hitting the most popular brands.

For this taste test, I had my girlfriend pour me each brand’s diet and zero-sugar soda at random in unmarked glasses. I tasted two at a time, wrote down initial impressions in my notes, took another taste of both to solidify my thoughts and declared a winner. Just to be clear, I never knew what brand I was tasting, save for Mountain Dew, but I listed which brand I was tasting below just to make this list a bit easier to navigate.

Let’s drink.

The Zero Sugar Diet Blind Taste Test

Round 1: Dr. Pepper

Diet Soda
Dane Rivera

Taste 1:

Diet Soda
Dane Rivera

A nice initial sizzle with a strong sweetness that hits the palate immediately. The flavor is a bit earthy with a slight fruitiness to it that is really nice. But the aftertaste stains the tongue in this really off-putting way. I’m not loving the finish on this one.

Taste 2:

Diet Soda
Dane Rivera

That sizzle from Taste 1 is about the same here, but there is a stronger burn on the tastebuds. This one has a little bit of bite to it that I’m liking. There is less of a fruit characteristic here than taste 1, but I’m getting a darker profile with a mix of sweet and bitter tones.

And The Winner Is…Dr. Pepper Zero Sugar (Taste 2)

Diet Soda
Dane Rivera

Two things set this one apart from the Diet formulation for me. The bite and the aftertaste. This may just be me but I like a soda that has a kick to it, this has that along with some sweetness and an aftertaste that doesn’t stick to the tongue like no-calorie sodas tend to have.

The Bottom Line:

Overall, both have echoes of full-sugar Dr. Pepper in different ways, but I think Dr. Pepper Zero Sugar captures that magic better.

Round 2: Pepsi

Diet Soda
Dane Rivera

Taste 1:

Diet Soda
Dane Rivera

I’m getting some chocolate character here, but I’m disappointed in the lack of fizz. There is no bite here, it has an intense and strong sweetness at the onset that never lets up. No subtlety — kind of one-note and boring.

Taste 2:

Diet Soda
Dane Rivera

Way more interesting than Taste 1, this comes across like an entirely different brand. I’m tasting a mix of cinnamon, sweetness, and a light bitterness here. There is more to latch onto and I found myself really enjoying my second taste. I ended up finishing the glass, I can’t say the same for Taste 1.

And The Winner Is… Diet Pepsi (Taste 2)

Diet Soda
Dane Rivera

I’m not a Pepsi fan in general, I find that the brand tends to be too sweet and not fizzy enough. While I can’t say this one was particularly fizzy, I did enjoy the bouquet of shifting flavors a lot. I might even go as far as saying I prefer this to the full-sugar Pepsi.

The Bottom Line:

Pepsi Zero-Sugar and Diet Pepsi couldn’t taste more different. Ultimately, Diet Pepsi had a more interesting blend of flavors that made drinking it a significantly better experience. Pepsi Zero-Sugar is downright undrinkable with how sweet it is.

Round 3: Mountain Dew

Diet Soda
Dane Rivera

Taste 1:

Diet Soda
Dane Rivera

Wow, is Mountain Dew f*cking weird. There is a sickly candy-like sweetness here. It’s so sweet that it straight up tastes like sugar, if you told me it was regular Mountain Dew, I’d believe you. On the backend is this interesting bitter rind flavor with a bit of a burn.

I’m struggling with this one.

Taste 2:

Diet Soda
Dane Rivera

And I thought Taste 1 was bad! This is horrid. It’s a bit more citrusy than Taste 1 with a gentler finish that stays sweet.

And The Winner Is… Mountain Dew Zero-Sugar (Taste 1)

Diet Soda
Dane Rivera

Make no mistake, I’m making this decision simply because I have to. I can’t say that I enjoyed either of these very much, but forced to choose, I’m going with Mountain Dew Zero-Sugar. That comes down, once again, to the burn. I just find this one more palatable, the Diet version was sweet to the point of being distracting.

The Bottom Line:

Mountain Dew has its audience, and I’m not it. If you like the intense sweetness of full-sugar Mountain Dew you might prefer the Diet version, but if you’re looking for something with a burn and a twist of bitterness, the Zero Sugar is the way to go.

Round 4: Coca-Cola (Taste 2)

Diet Soda
Dane Rivera

Taste 1:

Diet Soda
Dane Rivera

There is a mellowness to this one that is interesting. I don’t know how else to describe it other than to say it tastes soft. A quick hit of sweetness greets you and leaves the palate completely once you swallow. It’s elegant and gets the job done. It doesn’t taste like any soda I’m familiar with though, so if you’re a fan of whatever brand this one belongs to, I’m not sure if it works as a true substitute.

Taste 2:

Diet Soda
Dane Rivera

This couldn’t be more different than Taste 1, so much so that I asked my girlfriend if there was some sort of mixup and I was tasting two different brands. I’m getting a mix of dark, rich, and chocolate-forward flavors with a hint of cinnamon and vanilla on the backend. It’s very interesting and kind of tastes like one of those high-end bougie cola brands they sell at BevMo.

And The Winner Is…Coca-Cola Zero Sugar

Diet Soda
Dane Rivera

My all-time favorite soda is Coca-Cola so I was surprised to learn what I was tasting was from the brand. I have to give the winning slot here to Coca-Cola Zero. While I appreciate the clean flavor of Diet Coke, the Coca-Cola Zero just tastes more interesting thanks to its mix of cinnamon, chocolate, and vanilla tones.

The Diet Coke had none of that, though I stand by what I said when I called it “elegant.” At the end of the day Coca-Cola Zero Sugar offers a more interesting flavor. One I can see myself going back to.

The Bottom Line:

I won’t lie to you, if you like Coca-Cola, neither Diet Coke or Coca-Cola Zero Sugar taste anything like the real thing. They lack the bite, the harsh burn, and the deep flavor of Coca-Cola Classic. Having said that both are very interesting, with Coca-Cola Zero Sugar edging a bit closer to the real thing.