How I quit Diet Coke, and how it dramatically reduced my daily bloating (bringing my waist down by 6 inches). My experience is purely anecdotal (based on my personal account rather than research) and is not a substitute for professional medical advice.
Ninety-three days ago I decided to quit Diet Coke after a day-long binge. I knew Diet Coke wasn’t helping my health, but habit and enjoyment had kept me drinking it for years. Over the last year my waistline expanded dramatically from bloating even though I maintained my weight and stayed quite lean (under 110 lbs at 5 ft). At my worst my waist measured 31 inches and eventually settled around 25 inches after quitting.
Bloating Before and After Pictures
Although my weight stayed similar to previous years, my waist grew by as much as six inches at the peak of bloating and remained about four inches larger for several months. I suspected Diet Coke was a major contributor — I’d been drinking it for 25 years and only recently noticed this change.
At 110 lbs my waistline was larger than when I weighed 122 lbs a few years earlier. I believed the change was due to inflammation and water retention rather than fat gain.
Below is a comparison of my waist at the height of bloating (July 2021) versus three months after quitting Diet Coke (May 2022): 31 inches at the worst, 25 inches after quitting.
My symptoms from drinking too much Diet Coke
I tracked symptoms carefully to understand what might be related. Before quitting, I experienced:
- Needing to know where the bathroom was at all times; I couldn’t go anywhere without access to a restroom.
- A feeling of a weak bladder and frequent urge to urinate.
- Increasing joint pain and constant joint swelling sensation; my wedding ring felt tight.
- Severe abdominal bloating that spilled over my pants.
- Persistent thirst.
- Poor abdominal muscle control — trying to tighten my abs triggered the urge to pee and felt disconnected from my brain.
- A constant frenzied feeling, similar to caffeine agitation.
There were non-physical drawbacks as well:
- Frequent stops at gas stations to buy cans, wasting time.
- Excess trash from discarded cans.
- Feeling enslaved to the habit, drinking can after can without awareness.
- High expense from buying so many drinks.
Ruling out other causes of bloating
Last summer I pursued many possible medical explanations. I read books on bloating and visited a gastroenterologist convinced it was medical. Tests and steps I took included:
I tested for
- H. pylori — negative.
- Colonoscopy (I have a history of ulcerative colitis) — clear.
- Full IgE food allergy panel — same slight reactions I’d had for years to eggs, wheat and dairy; nothing new.
- CMP/CBC with differential — mostly normal.
- Giardia test — normal.
- Attempts at a low-FODMAP diet — which I tried and later reintroduced foods.
I also had persistent upper hamstring/lower glute pain that did not respond to X‑rays, steroid injection, acupuncture, CBD, ibuprofen, or physical therapy. Even taking time off running didn’t resolve it. I wondered if chemicals in diet soda could be contributing to joint pain, but solid scientific proof was lacking.
Deciding to quit
After exhausting medical explanations and recognizing the financial and lifestyle cost of the habit, I decided to stop. I didn’t want to quit at first — the habit was enjoyable and hard to give up — but I wanted to feel more comfortable in my clothes and reduce the bloating.
Steps I took to quit Diet Coke
I researched other people’s experiences quitting and borrowed strategies that worked for them. I chose to quit cold turkey because moderation wasn’t realistic for me: one can almost always led to another.
I also decided to consume the remaining cans in the house before I fully quit, which resulted in an embarrassing binge that reinforced how addictive the habit had become.
Step 1) I joined a Facebook support group
Because the research around diet beverages and long-term harm is mixed, anecdotal support was important for motivation. I found a Facebook group for people quitting diet drinks and spent a lot of time reading members’ success stories. Seeing others improve was highly motivating.
Step 2) I downloaded the Quitzilla app
I noticed many people in the group using an app called Quitzilla. It turned out to be extremely helpful. Tracking days of abstinence and seeing the progress visually made a big difference. The app’s daily motivational quotes and the idea of losing that streak discouraged me from giving in at social events.
Step 3) I replaced Diet Coke with sparkling water and caffeine pills
I craved the ritual and the burn of a soda can, so I swapped in sparkling water for the carbonation. At first I disliked fizzy water, but the bubbles satisfied the habit. I tried several brands and found a few affordable favorites that worked for me.
To prevent caffeine withdrawal headaches and match my previous caffeine intake, I took 100–200 mg caffeine pills in the morning. That simple replacement helped a lot.
Step 4) After two months I switched from carbonated drinks to flavored water mixes
After about two months of sparkling water I transitioned to flavored drink packets and plain water to eliminate carbonation before a bikini/bodybuilding show. I used unsweetened or stevia‑sweetened drink mixes and some zero‑calorie flavor drops. That change helped reduce any residual bloating from carbonation.
How I felt over time
I journaled the early days so I could track changes.
36 hours after my last drink
- My morning run felt energized and bouncy with better lung capacity and a tighter core.
- I added 10 lbs to my kickbacks, which previously had been limited by glute/hamstring pain.
- I had more evening energy.
- I experienced a bout of diarrhea, possibly related to shifts in gut function.
48 hours after my last drink
- My lower abdominal measurement decreased by about 1.5 inches.
- I had an exceptional morning run with no extreme post‑run fatigue.
Three months after my last drink
- I’m no longer constantly thirsty.
- My waist has reduced by about six inches from the worst bloated measurement.
- I’ve saved money by not buying cans.
- I no longer need to urinate constantly and feel more bladder control.
- Water retention has diminished, as shown by my wedding ring fitting more comfortably.
- I can feel and contract my abdominal muscles again.
Final thoughts on quitting Diet Coke
This is my personal story and not a scientific study, but quitting Diet Coke has improved how I feel physically and mentally. The combination of support, tools to track progress, and practical replacements for the ritual helped me succeed. If you’ve tried quitting Diet Coke or another diet beverage, I’d love to hear about your experience and any improvements you noticed.