Coke Zero vs. Diet Coke – What Is In These Diet Drinks, And Are They Actually Healthy?

“Hi, I love you. Don’t drink that.”
“I don’t know. It has poison or something in it. Just stop.”

This is the exact well-researched and informative conversation that happened between me and my partner the other day. He had just ordered a diet coke and I wanted to save his life. 

Sadly, I didn’t know exactly what I was saving him from. I had heard all of my life that diet coke was bad for you. As a child, my mom’s philosophy was that soft drinks would kill you and diet coke was the mastermind behind all the deaths. 

While my mom was right about a lot of things, the idea that sodas were all undercover murderers probably wasn’t her strongest point. So I did some research — here’s what I found.


What Makes a Soda “Diet”

Diet sodas first came on the market in the 1950’s. They were marketed to people who had diabetes but still wanted to enjoy sodas. As the popularity grew for the diet drinks, so did their audience and the sodas started being marketed to people who wanted to watch their weight or reduce their sugar intake. 

Diet sodas really have nothing — no sugar, no calories, no protein, and no fat. The thing that diet sodas do have is aspartame (aka the ‘poison’ in my earlier conversation). 

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Aspartame is the artificial sweetener that companies put into their diet drinks. While aspartame doesn’t add calories to your diet, it does increase your chance of obesity and metabolic syndrome. The danger doesn’t stop there. Aspartame also increases your appetite by triggering hunger hormones and dopamine responses in your brain. 

I don’t remember the last time I had a soda without something else. I love munching on peanuts or chips while I’m drinking a coke. In fact…I think it’s time for a snack break. 

While aspartame isn’t exactly healthy for you, it does have some benefits. If you’re trying to be a little healthier but you still want that soda fix, diet drinks are a better option than regular old sodas, which are packed with sugar. So how did aspartame get such a bad rap?

Aspartame in General

Whenever anyone warns against diet drinks, aspartame is the ingredient that comes up. So why is aspartame so bad?

It’s not. There are a ton of studies about aspartame, but no clear consensus stating whether or not the ingredient can be labeled “good” or “bad.” Aspartame is made up of aspartic acid and phenylalanine. These are two natural amino acids. 

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The toxicity comes from the free methanol that is produced when your body breaks down the aspartame. Basically, too much methanol is a bad thing. But methanol isn’t just made when your body breaks down diet foods. Methanol is also produced when you’re digesting things like fruits and veggies. So this really just means that you should diversify your diet. Diet soda isn’t the only place people will find aspartame, either — gum, yogurt, and basically anything that is “sugar free” or has reduced sugar in its description probably also has aspartame. So while it might be easy to point a finger at diet soda, aspartame is going to be hard to avoid completely. 

Aspartame is incredibly rich — it is about 200 times sweeter than sugar. While that’s an alarming concentration, it does mean that aspartame is not as prevalent in sodas as some think, or else it would overpower the taste. 

According to the FDA’s suggested use, a 150-pound person would have to drink more than 18 cans of soda a day to exceed the suggested daily intake. 

That being said, people with medical conditions like phenylketonuria or schizophrenia shouldn’t have aspartame because of the high volume of sweetener that these chemicals make.

What about Coke Zero?

I was actually shocked to find out Coke Zero had aspartame in it as well. I thought that Coke Zero would have strikingly different ingredients than Diet Coke, but it really doesn’t. 

The biggest difference between Diet Coke and Coke Zero is the taste. Coke Zero is supposed to mirror the original Coke taste while Diet Coke has its own flavor. I personally don’t like diet drinks because I can tell they taste a bit different than the classic sugary sweet taste of Coke. People will often describe Diet Coke as having a “lighter” taste, almost like you can taste the difference in calories.  

The makeup of these two drinks is almost identical too, but Diet Coke is made with citric acid while Coke Zero is made with sodium citrate. This is the biggest and only difference between these two sugar- and calorie-free Cokes.

Quitting Soda

Technically diet and zero-calorie sodas aren’t bad for you, but maybe don’t drink too many of them.

The amount of sodas people drink is often the real problem that comes with drinking soft drinks. They’re addictive. Also, because sodas are drinks, people don’t consume them as they do real food. With cookies, you can say you’re just going to eat one or two. You can nurse drinks all day because drinking isn’t something only done at meals. So how do you quit soda? 

1. Treat it like a dessert

Whether or not it has sugar in it, start treating soda like the sweet treat it is. Drink it after lunch or dinner, but not during. This way you’re not going through multiple cans of soda while you sit at the table, and you’re giving the sweet drink its own moment instead of losing its taste with every other bite.

2. Practice mindful drinking 

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My therapist taught me this trick and it’s amazing. We put so much into our bodies without realizing it. If you’re mindful and really focus on what you’re drinking when you’re drinking it, you’ll appreciate it more and drink or eat less of it. Mindful drinking and eating usually means putting away all distractions and just letting it be you and the food. There are actually a lot of meditations that focus on this topic. 

3. Pick a healthier drink

A big part of the allure that comes from soda is drinking something that isn’t water. If you want the flavor burst, maybe think of adding tea or coffee into the mix. When I need the sugary sweetness of soda, I’ll sometimes add something to my water to mix it up a bit. Some people also like kombucha and iced tea as well!

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4. Share a coke 

But actually! Maybe you and your partner both drink a bit too much Coke for your health. Suggest sharing a can whenever you open it. This will wean you off of drinking too much and also save y’all money! Plus you’re going into it with a partner. 

5. Only buy it sometimes

If you’re buying a pack of soda every time you go to the store, you’re going to end up drinking it. Next time you’re at the store, mindfully debate if you want the soda or not. My partner and I do this when we get alcohol. We debate if the occasion is special enough and how much to get. We know that the two of us shouldn’t buy a 12 pack for a date night, but a 6 pack will last us about a week. Either get smaller packs or only get them on special occasions.

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It’s possible to wean yourself off, but it’s okay to have some every now and then! Do you love Coke? What about Diet? Comment your soda preferences below!

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