Diet Pepsi caves to the ignorant

It had to happen. Somebody had to be the first. Maybe others will follow and maybe not but either way, this is a very bad idea.

What am I talking about? Pepsi has announced that they will be changing their recipe for Diet Pepsi to remove aspartame (“Nutrasweet”) and replace it with sucralose (“Splenda”). Diet Pepsi has been sweetened with a mix of aspartame and acesulfame-potassium (known as “ace-K”) for a couple of years, and the new formula will be a mix of sucralose and ace-K. Pepsi insists that they’re not doing it because of any problems with aspartame. They said “Decades of studies have shown that aspartame is safe. This is not about safety.” They say they’re doing it because their customers are demanding it, and because their sales are way down in recent years.

This statement is consistent with their actions. If it was about health or product safety, not only would they have said so (so they can be seen as being a company that cares about its customers), but they would be getting rid of aspartame in all of their products, not just Diet Pepsi. They have announced that only the various varieties of Diet Pepsi (i.e. caffeine free, cherry, etc.) would be changing; their other diet products like Diet Mountain Dew would not. Also, they are not removing it from Diet Pepsi in Canada, so it really doesn’t matter much to us Canadians.

As a type-2 diabetic, this is an important topic for me. Artificial sweeteners don’t raise blood sugar level like real sugar does, so products that use them are very important for diabetics. And yes, I do drink diet Pepsi and other diet soft drinks, though I prefer Coke Zero.

The Science

Aspartame is probably the most heavily tested food additive ever. It’s been in thousands of products since the 1980’s and has been approved and deemed safe for consumption by not only the FDA in the US but the equivalent agency in 100+ countries around the world. Yes, if you eat a spoonful of the stuff raw, it’s dangerous. But the reason it’s used is because it’s 200 times sweeter than sugar, which means you only need a tiny amount to sweeten whatever you’re putting it in. The amount used is so small that it has virtually no calories. If a person my size (~170 pounds) were to drink 21 cans of diet pop every day, that would bring him or her to the FDA’s level of “acceptable daily intake” (ADI) of aspartame, meaning he or she could drink that much every day for a lifetime “without appreciable health risk”*. Note that Health Canada’s ADI is lower than the FDA’s, so I could only drink 17 cans of diet pop per day. Awwwww.

* – This means no appreciable health risk from the aspartame. It’s not like there are no other health risks with drinking that much pop.

Have there been studies on rats that showed higher rates of lymphoma and leukemia with increased aspartame intake? Yes. But first off, those studies are a little suspect; some were testing rats ingesting amounts of aspartame equivalent to a person drinking a couple of thousand cans of diet pop per day. Secondly, rats aren’t people. Chocolate is deadly to dogs and cats but we don’t ban it for people and nobody says “this stuff will kill your dog, why would YOU eat it?”. There have been thousands of studies on the effects of aspartame on people over the past forty years, and none of them have shown any association between aspartame and various cancers. There have even been studies on people who claim to have “aspartame sensitivity” which showed that such a thing does not exist.

Zumwalt Meadow

(I tried to find a suitable picture for this article, but I did an image search for “aspartame” and the results were pretty much nothing but “aspartame is poison!” infographics containing incorrect information. So here’s a completely unrelated image of Zumwalt Meadow in Kings Canyon National Park in California. I’ve never been there but it looks lovely. This is from a photographer named Kevin Gong.)

There are people who have a genetic condition known as phenylketonuria (PKU) which causes the body to be unable to metabolize an amino acid called phenylalanine, which is one of the by-products of digesting aspartame. Those people are generally told to avoid aspartame, though they get more phenylalanine from their regular diet than from aspartame anyway. But this condition is rare and has other more far-reaching effects than just getting sick from aspartame – this is not the kind of thing you don’t know you have until you’re 30.

And no, it didn’t start out as ant poison until they accidentally realized how sweet it tasted. It started out as an anti-ulcer drug until they accidentally realized how sweet it tasted. I wonder if anyone has any idea how well it works to prevent ulcers?

Even better are the “oh yeah, who paid for that study?” people. First off, the fact that a study was paid for by a company doesn’t mean that company had a hand in the outcome. Second, good studies publish their data as well as their conclusions so that other scientists (who weren’t paid) can look it over and make sure it all was done correctly and the interpretation of the data makes sense. This is called peer-review and without it, studies are far less reliable. Third, studies that aren’t replicated by other scientists are also less reliable. And fourth, we have my standard question to believers of huge conspiracy theories: do you really think that 30+ years of peer-reviewed and replicated studies by hundreds of different scientists were all manipulated and falsified without anyone finding out or blowing the whistle? Show me the evidence for the conspiracy, and remember that things that are consistent with a conspiracy are not necessarily evidence of one.

The decision

So that’s the science. Nothing in science is ever 100% guaranteed, but as far as we can tell from a ton of testing, aspartame is safe to consume in the quantities that people are consuming it. Pepsi even acknowledges this. So why change? Due to customer demand. But why are customers demanding it? Are there really that many people out there with PKU who want to drink Diet Pepsi but can’t? No. It’s not PKU, it’s FUD.

FUD (fear, uncertainty, doubt) is something that people frequently use when talking about nutrition. Most anti-GMO and pro-organic articles you read on the web are based on FUD. The Food Babe makes her living off of it. (More like the FUD Babe, amirite?) (Dammit, someone else already said that) It’s essentially a logical fallacy that creates a false choice, then makes you afraid of one of the options (frequently using incorrect information or outright lies) to make it “obvious” that the other option must be the right one. But once somebody’s given you a reason to fear something, it’s very hard to see past it. So people end up avoiding whatever it is “just in case”.

Such is the case with aspartame. If hundreds (or thousands) of well-performed studies over decades show no association with any negative health effects (other than PKU), then it’s likely that there are none. But since science can’t prove beyond any doubt that it’s safe, people think that maybe it’s not. I suppose that’s technically true, but just because the options are “it’s safe” and “it’s not safe”, that doesn’t mean the two options are equally likely. Is it possible that every one of the thousands of aspartame studies showing that it’s safe are wrong or flawed? Sure it’s possible. But if you flip a coin 100 times and it comes up heads 99 of those times, it’s possible that you have a completely fair and balanced coin, but it’s far more likely that it’s not.



Ultimately, you know that the Food Babe and Dr. Oz and a zillion other people will point to this decision as “proof” that aspartame is dangerous. They won’t mention the science (why start now?). They won’t mention that Pepsi said that it’s not about safety (or they’ll imply that Pepsi was lying). They won’t mention the fact that Pepsi didn’t change their other diet drinks (which is inconsistent with Pepsi lying about safety, but they’ll say it anyway). They won’t mention that a soft drink company may not be the best place to get your nutritional information.

I commend Pepsi for stressing that this decision had everything to do with making customers happy and nothing to do with product safety. Despite what I said at the top of this article, I can’t really say this was a bad idea, since I have no idea how it will affect sales – if sales go up, then it was a great idea since that was the goal.

That said, I really wish they hadn’t done it. All this decision will do is imply that all of the FUD about aspartame is justified. Honestly, Pepsi can say whatever they want about safety or their reasons for doing this but in two years, nobody’s going to remember any of that. They’ll just see the Food Babe and others spin it as “don’t forget, Pepsi refused to continue including aspartame in Diet Pepsi!”

And science loses again.


American Cancer Society. (2014). Aspartame. Retrieved from

Choi, C. (April 24, 2015) Diet Pepsi Will Be Aspartame-Free, But Not In Canada. Huffington Post Canada.

Health Canada. (2005) Aspartame. Retrieved from

Health Canada. (2008) The Safety of Sugar Substitutes. Retrieved from

Horovitz, B. (April 24, 2015). Diet Pepsi to ditch the aspartame. USA Today (online). Retrieved from

National Cancer Institute. (2006). Aspartame and Cancer: Questions and Answers. Retrieved from

National Cancer Institute. (2009). Artificial Sweeteners and Cancer. Retrieved from

Pomeroy, R. (undated). Study Finds No Evidence for ‘Aspartame Sensitivity’. Real Clear Science. Retrieved from

U.S. Food and Drug Administration. (2014). Additional Information about High-Intensity Sweeteners Permitted for use in Food in the United States. Retrieved from

Wikipedia. (2014). Aspartame. Retrieved from


Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s