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Cutting Diet - A Few Concerns about Diet Soda

hey, guys. I’m cutting for a while and keeping myself on this coffee and water routine is driving me nuts. Can I drink Pepsi Twist zero without affecting my fat loss? I can’t take it anymore, coffee tastes really bad and is driving me crazy. What are your thoughts on diet soda drinks? Yeah, I know…it’s not healthy and gives you cancer, but other than the cancer issue, for god sake…can I drink it without worries? it tastes so much better than coffee (and water), my only concern is regarding the fat loss. thanks.

If it drives you insane yeah for all means go for it. It never harmed my fat loss (or I didn’t notice). But don’t start drinking gallons of it

thanks, bud. yeah, maybe I’m getting insane already because of restriction. I hate black coffee so much yet I still drink a lot of this stuff trying to curb my huge appetite. Today I allowed myself to drink (I’m still cutting today) pepsi twist zero cal and I tell you, it was like a orgasm, I almost cried. I don’t know that much about aspartame/acesulfame potassium sweetners halting weight loss like these papers claim, maybe it’s just happening for the rats they’ve tested. well, actually I don’t bite it 100% that’s why I’m here asking you. My brain just need some pleasure while on a diet aiming weight loss, come on…even a diet pleasure, otherwise I’ll ending up slashing my wrists.

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I cut down to 8.4% bodyfat on a BODPOD drinking like half a gallon of diet soda a day. Posted about my experience here


Yeah I used to be crazy about diet soda too. Used to drink almost a gallon and lost 30 kilos. But damn that was a lot of caffeine, acidity etc

hey, thanks for the replies. I’m glad to know I can be happy doing that then lol P.S.: can someone link me the stickies? I heard there are stickies about hormones, I can’t find them anywhere. Thanks.

The problem I have with diet soda is that it elevates insulin. Sure if it helps you stick with the diet, then go for it by all means. It’s better to have a diet with diet soda and stick to it, than to have one without it, while being on the verge of insanity trying no to break it (and ultiately probably failing).

It’s good from a mental point of view, so I’d say drink as much as you want, but statement that diet soda is guiltfree on a diet is far from truth.

No they do not


Zevia is a healthier alternative to standard diet soda. 0 calories, sweetened with stevia, no food coloring.

Just my .02, I think you need to check your motivation levels and stop whining. Wow. What a victim. I’m going to slit my wrists because I can’t drink diet soda. Are you serious? If so, man up and stop drinking it, or drink it and stop asking for validation to drink it.

“Other than the cancer issue, can I drink it without worries?” Other than the cancer issue, could you smoke cigarettes without worries? Sure, go for it, doesn’t change the cancer issue.

You’re looking for someone to validate your poor decisions. If you want to drink diet soda, do it, no one else’s opinion is going to change the harmful effects of it.

Again, I highly recommend Zevia. I drink a couple a day and have for years, including during competition prep.


That’s a matter of opinion, at best, since “healthy” is a very relative term.

Drinking 12 cups of coffee every day is arguably unhealthy, but that hasn’t stopped you from doing it. Some people say TRT isn’t healthy and will cause heart attacks and cancer, but you’ve likely researched enough to realize that they’re wrong.

Urban legend based off bad science: https://www.t-nation.com/diet-fat-loss/the-not-so-scary-truth-about-sweeteners
"These three studies linked aspartame with leukemia, lymphoma, and kidney cancers. The studies involved mice, though, and a lot of scientists maintain that the studies were also shoddily conducted.

Even if you choose to give those studies more credence than they might deserve, you have to weigh and contrast them against the findings of the National Cancer Institute. The NCI examined the cancer rates of more than 500,000 people who drank aspartame beverages and they didn’t have higher cancer rates than non-aspartame drinking people."

This is a sentence I’d expect to see from a pre-contest bodybuilder with paper-thin skin having his first cheat meal in 13 weeks, not some dude “on a diet aiming for weight loss”.

Have some perspective. You sound as bad as the guys who ask if they should pack a cooler to bring their own food to Aunt Dottie’s Thanksgiving. Fucking no.

Just to drop one more mind-expander in here, give this a read:

In particular: "Peters and associates did a one-year study comparing the effects of a group that drank artificially sweetened sodas to a group that drank water. The program consisted of 12 weeks of dieting followed by 40 weeks of maintenance.

The group that drank diet drinks lost more weight during the 12-week weight loss period. They also had greater reductions in waist size, along with reductions in cholesterol, LDL, triglycerides, and blood pressure than the water group."

So have your Pepsi but try not to cream your jeans.

You can find them here, but take them with a proverbial grain of salt. They’re due to be re-worked and improved for accuracy.


Thanks, Chris for saving me the trouble. FFS… As with most everything, everything in moderation. From an ‘aspartame is responsible for every ill known to man’ perspective, try to keep your diet soda consumption under roughly 6 cans per day (if my memory serves me; easy to look up for the OP poster). That alone would seem to solve all of your “diet soda concerns”.

The problem I have with diet soda is that it elevates insulin.

I’m a type 1 diabetic and wear a continuous glucose monitor 24 hours a day. Diet soda does not elevate insulin or elevate blood sugars in any way.


To explore the impact of diet soda consumption on insulin levels, researchers in a December 2009 study published in “Diabetes Care” provided participants with liquid glucose and either diet soda or carbonated water, testing glucose and hormone levels frequently over a three-hour period. While glucose and insulin levels did not differ significantly between the two groups, those who had consumed diet soda had significantly higher levels of glucagon-like peptide-1 (GLP-1). GLP-1 is a hormone that can help control blood sugar via different mechanisms – and one of its roles is to stimulate insulin production. Researchers hypothesized that changes in GLP-1 levels were from the stimulation of the sweet taste receptors.

So they showed that GLP-1 doesn’t raise insulin/glucose levels.

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Interesting, as Dr Ryan Lowery was discussing this recently and he claimed they had tested blood glucose after diet soda consumption and it did impact on insulin levels. I’ve heard the same thing anecdotally. This is apparently the main advantage of erythritol over other sweetners.

I think the bottom line is that it is processed food. If you’re mainly health-focussed then you’ll ditch it. But if it’s one of life’s last remaining pleasures when you’re on a diet then you’ll embrace it - by the gallon. I recall Shelby Starnes saying this on this very site years ago.

Where was this? If it is the keto guy he posted a couple months ago that it does not.

Did he just drink diet soda or drink it with food? There are some AMA studies showing that diet soda with a meal raises the insulin release for the given meal. It also shows that the insulin release amounts to hyper secretion, so a T1D (type 1 diabetic person) would not REQUIRE insulin or see a blood sugar rise from the artificial sweetener but a person making their own insulin would tend to OVER release insulin (causing overexposure that can result in the development of insulin resistance and type 2 diabetes) and then that person would have a release of glucagon and other counter-regulatory hormones to prevent hypoglycemia from the higher levels of insulin. The main mechanism of progressive insulin resistance and type-2 diabetes seems to be an over-secretion of insulin in response to a fast rise in blood sugar resulting in desensitization to insulin. Most T2Ds exhibited rebound hypoglycemia earlier in life to developing T2D.

By the way, that’s one of the biggest benefits of low carb/keto dieting, that blood sugar becomes very stable (varying by maybe +/-10 points) and so there is no over-secretion by the pancreas that comes from high spikes. Recent studies of diabetics have found that blood sugar swings are the main cause of the development of complications because cells experience fast changes in osmotic pressure that causes damage, especially to eyes, nerves and pancreatic cells. There is a type of diabetes (a form of MODY) in which subjects have blood sugar averages in the 170-210 range and A1Cs around 8, but they have normal variability because they make their own insulin, but have a higher baseline blood sugar. They have ZERO increased risk of diabetic complications, suggesting that it is not high blood sugar, but rapid swings in blood sugar that result in most if not all of diabetic complications.


The other concern I have with diet sodas is the emerging evidence of a link to leaky gut, or at least abnormal gut flora.

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I’ve cut from 200 pounds to 160 pounds in the last year and I drink probably 10 diet sodas a day.

Didn’t want to start a new diet drink thread so ressurecting this one for some info:


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