I'm a Diet Coke fiend who gave it up for a month, and I was surprised by how quickly I stopped craving it

  • I’m a Diet Coke fiend, and at the end of 2019 I was drinking a can most days.
  • Both studies and experts say conflicting things about the health and weight implications of consuming artificially sweetened soft drinks, but I suspected it wasn’t good for me.
  • I stopped drinking Diet Coke for a month to see how it affected me, and I realized I wasn’t as reliant on it as I thought.
  • However, while I’d been hoping my afternoon snack cravings might disappear, they didn’t, and my body, focus, and energy levels didn’t change either.
  • Visit Insider’s homepage for more stories.

I really love Diet Coke.

Or Coke Zero, depending on my mood. Actually sometimes I even go wild and opt for a Pepsi Max. 

No calories! No sugar! But all the deliciousness, refreshment, and caffeine!

I have consumed sugar-free soft drinks for as long as I can remember, despite the fact that I know they’re full of artificial ingredients and sweeteners. As someone who prioritizes eating a balanced diet and following a healthy lifestyle, my friends and family are always surprised that I am such a Diet Coke fiend.

I know, it doesn’t make sense. But I just love Diet Coke — or DC, if you will (you won’t?).

Towards the end of 2019, I realized my consumption was getting particularly high, and I was drinking a Diet Coke (or another sugar-free soft drink) most days. 

Scientific opinion on diet sodas is mixed

It seems like every health, fitness, or nutrition expert you speak to says something different about diet sodas, and the studies into the area reach equally confusing conclusions.

The overall health implications of consuming artificial sweeteners are widely contested, and the same goes for their impact on weight management.

There has been some research which suggests drinking diet sodas is linked to increased risk of stroke and Alzheimer’s, as well as diabetes.

However, researchers note that in most of these cases it’s hard to draw solid conclusions as you can never fully account for other lifestyle factors which may contribute to these diseases — it could be that people who drink more diet soda are doing so because they’re already overweight, for example, and it’s that which actually results in the health problems. 

When it comes to weight management, while some studies claim consumption of diet sodas is bad — for example, it’s been linked to weight gain by making people crave more sugarothers say it can be beneficial for weight loss by curbing cravings without adding any calories.

Sports nutritionist Scott Baptie, for example, previously told Insider he encourages his clients to drink diet soft drinks to help them slim down — however, the ultimate goal is to transition to water.

I wondered whether the drinks affect each of us differently, and there was only one way to find out how diet drinks were affecting me: cut them out completely.

Ultimately, I knew it wasn’t good for me, so decided to set myself a challenge to go cold turkey for a month to see if I actually noticed any difference.

The rules of the challenge had to be clear

When setting out my challenge, it was hard to know where to draw the line. Obviously no diet cola of any kind, but I knew that if I only cut out those drinks I would simply transfer to other sugar-free sodas like Diet 7Up or Diet Dr Pepper, which rather defeats the point.

I decided sodas of all kinds would be out, but other flavored soft drinks were allowed.

Opting to take on my challenge in January also made it extra difficult because I was doing Dry January — when I’ve given up booze before, Diet Coke has been my go-to drink when out for dinner or having drinks with friends (unless a non-alcoholic spirit like Seedlip or Ceder’s is available) because even though it’s not a G&T, it’s more interesting than water. 

Week One: The cravings are real

Is there anything better than a crisp, sweet can of Coke Zero when you’re feeling, well, somewhat delicate after a night of celebrations? There would be no comforting my sore head on New Years’ Day with a fizzy drink this year. Surprisingly, I survived.

It wasn’t until January 2 that my first real craving hit, and it was only when I saw a colleague drinking Diet Coke. I suddenly had an overwhelming desire for that sweet, fizzy nectar.

I considered buying some sparkling flavored water on my lunch break to fill the void inside me, but I figured I was trying to save money as much as anything else, so resisted.

And that attitude lasted all of one day.

Fanta Grape Zero was calling to me.
Rachel Hosie/Insider

Exhausted from a bad’s night sleep, on January 3 I was craving, well, everything, so naturally I went to buy sustenance. When perusing soft drink options in Boots, I happened upon Fanta Grape Zero. Fanta Grape Zero! How had I never tried such a delectable-sounding libation? I wanted it so badly, but it would have been breaking the rules.

Instead, I bought a Vit Hit, which are low-calorie drinks made from vitamins, juice, water, and tea. They are, by all accounts, delicious, and no doubt healthier than a diet soda. However, they do still contain artificial sweeteners, and at £1.90 ($2.50) for a 500ml bottle, they’re more expensive than your average soda, too.

Vit Hit: delicious, but more expensive than a Coke.
Rachel Hosie/Insider

So much for saving money.

Week Two: Trying to be healthier is more expensive

As the month went on, I found myself spending more by trying to choose healthier options — kombucha, for example, costs a lot more than Coke.

I do of course realize that the healthiest option of all, water, is free, but I already drink vast quantities of straight-up H2O, so I really enjoy mixing it up with something flavorful.

Read more  Eating A Plant-Based Diet For Weight Loss

Over the course of the month I tried a lot of different soft drinks, from peach and pear flavored sugar-free iced green tea (almost definitely not very nutritious) to black raspberry flavored sparkling water.

I wasn’t convinced this was actually any healthier than a Diet Coke.
Rachel Hosie/Insider

My costs were rising, so I decided to try a new strategy and buy a bottle of every Brit’s favourite childhood drink, squash (a fruit concentrate which you dilute with water).

A lot cheaper than buying an individual bottle or can of something most days (and better for the environment), squash still contains artificial sweeteners and preservatives, so I wasn’t sure if I was doing my health much good or not.

It did fill the Diet Coke gap somewhat, though.

Week Three: Traveling poses an extra challenge

In the middle of January, I went to Finland for a week, and I realized I usually drink a lot of Diet Coke both on travel days and when abroad. Honestly, I missed it.

For starters, European Diet Coke is actually my favourite of all diet cola variants (yes, it tastes different to UK Diet Coke — like a cross between our Diet Coke and Diet Pepsi, if you’re interested). I was sad not to be able to enjoy it.

On the flip-side, I had fun Finnish drinks to try, like flavored vitamin waters and something called a Kane’s Ruby Hill Thrill which was a delicious fizzy strawberry drink.

The color of this alone suggests it not exactly natural.
Rachel Hosie/Insider

I’ll be honest, I wasn’t entirely sure if it should be classed as a diet soda, but I figured if I didn’t really know what it was, it was allowed. (Debatable, I know.)

Week Four: The cravings were definitely lessening

As I neared the end of my month sans DC, I realized my cravings for it had definitely decreased.

They hadn’t completely disappeared, though — it was often when I saw someone else drinking some, or heard that gloriously satisfying sound of a can being opened, that I found I suddenly wanted one.

I didn’t cave, but I was drinking squash at an alarming rate.

Squash for the win.
Rachel Hosie/Insider

I considered buying bottled sparkling water thinking that it would be better health-wise than an artificially sweetened beverage, but I felt too bad about the plastic, so I resisted. I concluded that for the health of both the planet and myself I should really just drink water from the tap.

I’m not going to cut Diet Coke out completely, but I will cut down

On February 1, I had my first Diet Coke in a month and it was, well, underwhelming. Yes, I enjoyed it, but it didn’t feel like coming home or anything.

Honestly, I didn’t notice any drastic enough benefits to make me want to cut Diet Coke out of my life completely (that might be a different story had I not drunk any soft drinks).

I was hoping my afternoon snack cravings might magically disappear when I stopped drinking diet soda, but I’m not convinced they did. My cravings changed day to day, but that happens normally.

My energy levels didn’t change, nor did my focus or body. It was all rather anti-climactic.

I may never give up Diet Coke all together.
Rachel Hosie/Insider

I don’t need Diet Coke to get me through an afternoon. I just quite enjoy it.

That said, I am going to try and limit my diet soda consumption to one or two a week. I know they’re not good for me, so I hope I can gradually wean myself off all soft drinks and be one of those beacons of health who only drink water. Maybe.

At the end of the day (well, month), I believe in moderation and having a little bit of everything you fancy as part of a balanced diet. That’s the key though: a little bit. Not seven cans a week.

A sports nutritionist says drinking Diet Coke will help you lose weight, despite a new study that suggests the opposite

There’s even more evidence that drinking diet soda is bad for you

Low-calorie sweeteners are no better for weight loss than sugar, according to a new study

— Update: 02-01-2023 — cohaitungchi.com found an additional article Is Diet Soda Bad for You? (Should I Drink Diet Coke for Weight Loss?) from the website www.nerdfitness.com for the keyword diet coke weight loss.

Diet coke weight loss

There’s one question we get asked more than any other: “

People want to know if Diet Coke will make them fat and make them sick, or if it’s all just a bunch of hoopla about nothing.  

We help our clients navigate challenges with soda (diet or not) in our 1-on-1 Online Coaching Program, and we’re gonna tell you everything you need about diet soda below.

Here’s what we’ll cover:

  • Does drinking diet soda lead to weight gain?
  • Will drinking diet soda make me crave actual sugar?
  • Does my body process artificial sweeteners just like sugar? 
  • Can drinking diet soda cause cancer? (Is aspartame or saccharin dangerous?)
  • How many diet sodas can I have in a day? 
  • Can you be addicted to diet soda?
  • Is Diet Coke worse for you than regular Coke?
  • Is drinking diet soda bad for weight loss? (Next steps)

Let’s get right to it!

Does Drinking Diet Soda Lead to Weight Gain?

Diet coke weight loss

Does drinking diet soda make you fat?

No, it does not.[1] 

It would be super evil if it did, what with the whole “diet” thing and all.

Diet sodas utilize “high-intensity sweeteners” which is a fancy term for very-low-calorie (or zero-calorie) sugar substitutes:

  • Acesulfame Potassium
  • Advantame
  • Aspartame
  • Monk Fruit Extract 
  • Neotame
  • Saccharin
  • Sucralose
  • Stevia 

The FDA has approved these eight high-intensity sweeteners for human consumption.[2] You’ll find them in all sorts of food products, not just diet drinks. 

Because high-intensity sweeteners are many times sweeter than table sugar, you can make a drink taste “sweet” without including any sugar at all. 

Most important, without the sugar, you’re skipping out on all the calories that come with it.

Weight loss depends on consuming fewer calories than you burn, so drinking Diet Coke compared to regular Coke can help tip the equation in favor of “weight loss.”

  • 12 oz Diet Coke total calorie count: 0
  • 12 oz Coca-Cola total calorie count: 150

If you’re trying to lose weight, but love fizzy carbonated and caffeinated beverages, the soda with fewer calories seems like a no-brainer.

Diet coke weight loss

The concern of drinking diet soda generally rests on three points:

  1. Drinking diet soda will make you crave real sugar.
  2. Your body processes high-intensity sweeteners just like actual sugar.
  3. Artificial sweeteners (like aspartame) can make you sick or cause cancer.

We’ll hit each of these points with its own section below.

Before we continue, I need to make a strong caveat: most studies on diet soda treat all high-intensity sweeteners as one.[3] This is concerning considering there are eight approved high-intensity sweeteners in use.

Read more  Silent Reflux May Respond Better to Plant Diet

Does your body process all eight the same? 

Diet coke weight loss

Some early studies on various sweeteners do show our bodies process them differently.[4]

More studies are being done on individual high-intensity sweeteners as we speak, so expect new information on the subject to unfold.

For now…

Will Drinking Diet Soda Make Me Crave Actual Sugar?

Diet coke weight loss

If you eat a bunch of sugary and sweet food regularly, your body can start to crave more of it.[5]

In other words, consistently eating sugary foods in the afternoon can result in an urge for sweets after lunch. 

These cravings can make it difficult to turn down the bowl of M&M’s as you pass Debra’s desk (She’s even got the peanut kind!).

Diet coke weight loss

The question becomes, do the high-intensity sweeteners found in diet soda make us crave sugary foods?

The research on this isn’t clear: 

  • Studies done on rats have shown a positive correlation between high-intensity sweeteners and sugar cravings.[6]
  • A 2019 meta-analysis found two studies where aspartame was added directly to the diets of humans. The result? Those who consumed the high-intensity sweeteners found their sugar craving to be LOWER.[7]

There might be something to the thought that drinking a Diet Coke can help satisfy the sugar craving.

As long as you remember: “correlation doesn’t prove causation!” 

Anecdotally, many of our coaching clients claim that grabbing a diet soda helps them from drinking the regular sugar-filled version. This can be really important, because “cravings” are one of the top issues facing most of our clients.

Which is why we work closely to identify possible food addictions in our 1-on-1 Online Coaching Program, so we can start to work through them together. Our strategy is to take it slow, to make small changes to alter these cravings. Over time, this is the best way to see real progress. 

If you’d like to learn how we can help battle sugar cravings, click below:

Does My Body Process Artificial Sweeteners Just like Sugar?

Diet coke weight loss

Another concern of drinking diet soda rests on the idea that your body processes high-intensity sweeteners as it would normal sugar.

The argument states that these sweeteners are so sweet that they fool your body into thinking it’s consuming actual sugar. 

After drinking diet soda, your body responds as it would after consuming normal table sugar: by dumping out insulin. This slows down the fat-burning process.

That’s the gist of it, more or less.

Do high-intensity sweeteners trick our bodies into releasing hormones (insulin)?

Again, the studies on this are mixed:

  • The high-intensity sweeteners sucralose and saccharin were both shown to provide a small insulin response in men.[8] 
  • Aspartame does not appear to elicit the same hormone response.[9] 


Diet coke weight loss

This isn’t a HUGE deal. Of all the things to worry about with regards to weight loss or getting healthy, this doesn’t hold the top spot on the list.

While hormones do play a role in weight loss, the main determining factor will always be an energy balance (calories in vs. calories out).

Since most diet sodas have next to zero calories, I’d say the insulin response of high-intensity sweeteners isn’t that important for your weight loss journey.

There are far better targets in the quest to eat healthy, like eating lots of vegetables and eating enough protein at every meal.

Can Drinking Diet Soda Cause Cancer? (Is Aspartame or Saccharin Dangerous?)

Diet coke weight loss

The other concern people have about diet soda is that it will cause cancer and kill them and everyone they know.

A little hyperbolic perhaps, but…

Should we be worried about the ingredients of diet soda causing us harm?

Some history is in order:

Why the reintroduction? 

Because no cancer link has ever been shown for the human consumption of saccharin. And folks have looked.[11] A lot.[12] 

Not everything that is cancerous to rats is harmful to people, and vice versa. 

Plus, you would have to drink 800 cans of diet soda to get to the levels of saccharin given to the rats in the study.

Even an all-night binge of would only put a small fraction of a dent in that.

Diet coke weight loss

How about aspartame or any of these other high-intensity sweeteners…

Are they sketchy?

Earlier I stated the FDA, the United States’ regulation agency, approved eight high-intensity sweeteners.

They aren’t the only agency that has done so. Australia, the EU, Japan, and Canada have all reviewed and approved these sweeteners.[13] They did so after a thorough investigation. 

Diet coke weight loss

So it’s safe to say that high-intensity sweeteners are okay to be used in a reasonable amount.

This brings up the question…

How Many Diet Sodas Can I Have in a Day?

Diet coke weight loss

While the sweeteners in diet soda have been approved safe for human consumption, there is a limit to this approval.[14] But I won’t make you pore over charts and do the math…I’ll do that for you.

What’s the number of 12-ounce diet sodas deemed safe in a day?


Which is A LOT of diet soda. 

However, it should be noted that diet soda is not the only place high-intensity sweeteners are found. 

Many other food products utilize these sweeteners to cut back on sugar and calories. So keep an eye on protein bars, yogurts, baked goods, etc, for hidden high-intensity sweeteners.

The other concern with drinking lots of diet soda would be the caffeine. Caffeine in moderate amounts is fine, but if you go overboard you could increase your anxiety and interfere with your sleep.[15] 

Diet coke weight loss

There’s about half the caffeine in Diet Coke versus a regular cup of coffee, which is still a decent amount. 

If you have trouble sleeping at night, consider how late in the day you’re having your last can of soda. Perhaps install a 2pm “caffeine cutoff” if you find yourself tossing and turning at night. 

Another problem with diet soda: most of them contain exactly zero nutrients. It’s water, some kind of sweetener (sugar or not), flavoring, coloring, and carbonation.

Drinks like coffee and tea actually have some antioxidants present, so you might be getting some benefits with these caffeinated drinks.[16] 

If you find yourself drinking lots of diet soda, consider mixing in some coffee or tea as a partial replacement. 

Sparkling water might help with the switch too, if you love those fizzy bubbles.

Read more  12 Of The Best Weight Loss Apps That Are Totally Free

At this point, we should note that stopping diet soda consumption might be easier said than done.

Can You Be Addicted to Diet Soda?

Diet coke weight loss

Diet coke weight loss

The Coca-Cola Company hires folks to find the perfect combination of:

  • Carbonation. The bubbles actually burn your tongue a little, which provides a pleasurable experience. Kind of like a good hot sauce. 
  • Sweeteners. Sure, it isn’t sugar, but your brain likes them just the same.
  • Caffeine. The jolt from caffeine will provide you a boost and raise your dopamine levels. The brain likes this.
  • Flavor. After drinking Diet Coke for some time, your brain will start to associate the flavors with carbonation, sweeteners, and caffeine. Which will make you start craving the flavor of Diet Coke. This is probably part of the reason people become brand loyal to particular diet beverages. 

How do you know if you have an addiction? If you find yourself approaching our 18 can a day safety limit, that’s definitely a sign. 

Another would be if you find diet soda interfering with your life (not sleeping after drinking Diet Coke all evening).

You don’t have to go cold turkey on this one: 

  • If you normally drink six cans of diet soda a day, try five.
  • After a month or so of this, try four.

This is the exact strategy we follow with our 1-on-1 Online Coaching clients, and it’s the most likely to succeed. 

Small changes over time are the ticket to permanent success.

Is Diet Coke Worse for You Than Regular Coke?

Diet coke weight loss

Before you use this article as justification to start drinking a six-pack of Diet Coke a day, let’s talk about some other possible concerns.

We’ve talked about all the mechanisms in diet soda that can make it unhealthy (high-intensity sweeteners, caffeine, etc). My conclusion is that these factors are likely overblown.

However, we should acknowledge that drinking diet soda can often be linked to health issues:

  • Despite diet sodas containing low to zero calories, drinking them is correlated with obesity.[18] Is this just because people who are overweight are more likely to consume a “diet” drink? We don’t know.
  • Diet soda consumption has been associated with kidney disease.[19] Is this because of the high phosphorus content of diet soda, or because people who drink soda have a poorer diet than those who don’t? This has still yet to be answered.
  • Soda, even the diet version, isn’t great for your teeth.[20] Diet sodas are acidic, leading to the erosion of tooth enamel. Although to be fair, this study found the acids in orange juice more corrosive than Diet Coke.[21]

There’s an important point here: drinking soda is also linked to kidney disease, teeth erosion, and obesity. Even more so those last two points (because of all the sugar and calories).[22] 

So the concerns of drinking diet soda would also be found in drinking regular soda…even more so.

Drinking Diet Coke may be the lesser of two evils here. 

Is Drinking Diet Soda Bad for Weight Loss? (Next Steps)

Diet coke weight loss

If you’re starting your weight loss journey and wondering where diet soda fits into the picture, I want you to know I’m proud of you.

You’re starting to ask questions and you’re looking for answers. This is a great first step.

If you’re trying to lose weight and currently drinking regular soda, the switch to diet would be a good move. 

You’re gonna consume fewer calories that way, critical for weight loss.

This is why one of our top recommendations to our coaching clients is to cut back on sugary drinks. 

However, if you currently drink diet soda and are trying to lose weight, there might be some better targets to shoot for:

  • Make sure every meal has a solid protein source.
  • Try to add some vegetables to your plate.
  • Get comfortable in the kitchen and experiment with making your own meals. 

These are far more important than an occasional Diet Coke here and there.

If you find yourself firing on all cylinders (you eat well, you strength train, you get lots of sleep), then maybe consider replacing diet soda with tea, coffee, or carbonated water. There are enough unanswered questions on consuming diet soda to warrant the switch. 

The most important thing you can do now? Commit to a change:

  • One less regular soda a day
  • One less Diet Coke a day
  • A daily walk first thing in the morning

Pick something you can track. Something with a clear “yes or no” that you can reflect on at the end of the day.

This will help you start your weight loss journey.

Diet coke weight loss

Want some help getting going? A little nudge out the door?

Okay, but only because you’ve been nice this whole time:

#1) Our 1-on-1 Online Coaching Program: a coaching program for busy people to help them make better food choices, stay accountable, and get healthier, permanently.

You can schedule a free call with our team so we can get to know you and see if our coaching program is right for you. Just click on the image below for more details:

Diet coke weight loss

#2) If you want an exact blueprint leveling up your nutrition, check out Nerd Fitness Journey! Our fun habit-building app helps you exercise more frequently, eat healthier, and level up your life (literally).

It’ll also provide a step-by-step plan from moving away from regular sodar, perhaps to a diet version or even tea.

Try your free trial right here:

#3) Join The Rebellion! We have a free email newsletter that we send out twice per week, full of tips and tricks to help you get healthy, get strong, and have fun doing so. 

I’ll also send you tons of free guides that you can use to start leveling up your life too:

Alright, I think that just about does it for me.

Now, your turn!

Share your story in the comments!


PS –

Check out the rest of our sustainable weight loss content:

  • 5 Rules of Weight Loss
  • Which Diet is Right for Me?
  • Start Eating Healthy Without Being Miserable

PSS: I want to give a hat-tip to Precision Nutrition, whose fascinating article served as the inspiration for this post. 


Photo source: Corrie Miracle: Diet Coke, Zeyus Media: Sugar Spoon, Stavos: ScientistEmmi: GollumSarah Korf: nutritional information, Ryan Hyde: Water, Mike Mozart: Diet Coke, Laura Lewis: mirror, Mike Mozart: Diet Coke


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About the Author: Tung Chi