Nature Artificial Sweetener Study Bogus, Says American Council on Science and Health

The folks over at the invaluable science watchdog group, the American Council on Science and Health, are calling foul on the new Nature study purporting to show that three different artificial sweetners boost blood glucose levels in mice and in four of seven human research subjects. ACSH chemist Josh Bloom suggests that it is very unlikley that three very different chemical compounds that just happen to taste sweet, sucralose, aspartame, and saccharin, would all have the exact same biological effect.
ACSH points out:
Dr. Bloom explains, "The premise of this study—that artificial sweeteners affect the microbial composition in the gut—makes absolutely no sense chemically, physiologically, or pharmacologically. The authors are taking chemicals that have exactly one thing in common—sweetness—and trying to correlate this with changes in gut bacteria that may be responsible for raising blood sugar — and in mice, no less!." …
What is the problem?
It is the absolute lack of any biologically plausible hypothesis to explain, well, anything really.
Why is this? Sweetness is a function of the interaction of certain molecules with the sweet receptors on the tongue.
Dr. Bloom: "There is a wide variety of chemicals that are sweet, both synthetic and naturally occurring. They have exactly one thing in common—taste. What can this possibly have to do with an effect on gut bacteria? Nothing.
"The authors really should have dug up a chemist before they got involved with this silly study. There are plenty of us around—mostly unemployed. Because he/she would have pointed out the gaping hole in the logic of the study—that you cannot group a chemically diverse group of chemicals simply because they are sweet, and draw any conclusion whatsoever about anything other that the taste.
Dr. Bloom continues, "It might be possible (although still highly unlikely) that any single sweet chemical could have some effect on (you name it), but to then lump in other chemicals that have nothing in common structurally or chemically is ludicrous. You might as well take random chemicals out of a lab and test them, because chemically, this is essentially what they did."
He adds. "As a chemist, if I saw a bunch of unrelated chemicals doing the the same thing in a test, my mind would start screaming 'the biology is a mess.' This was borne out hundreds of times during my career. It is one of the most important issues in drug discovery—whether the biology makes sense." …
"This just doesn't add up. You could just as well group chemicals together because they are yellow. It makes as much sense."
The researchers claim that fecal transplants with presumably altered gut microflora from affected mice to naive mice produced the same blood glucose spike. It should be easy enough to replicate these experiments.
See my earlier and sadly more credulous blog on the study here. I did say that I would continue dose my caffeinated beverages with Splenda.
Editor's Note: As of February 29, 2024, commenting privileges on reason.com posts are limited to Reason Plus subscribers. Past commenters are grandfathered in for a temporary period. Subscribe here to preserve your ability to comment. Your Reason Plus subscription also gives you an ad-free version of reason.com, along with full access to the digital edition and archives of Reason magazine. We request that comments be civil and on-topic. We do not moderate or assume any responsibility for comments, which are owned by the readers who post them. Comments do not represent the views of reason.com or Reason Foundation. We reserve the right to delete any comment and ban commenters for any reason at any time. Comments may only be edited within 5 minutes of posting. Report abuses.
Please
to post comments
Very good point. Did the study indicate WHICH sweeteners they used? Did they have separate groups using different sweeteners? Did they mix the sweeteners together?
Surely they should have something to say about the relative effect of sucralose vs. aspartame vs. saccarin.
(Don't have time to read the original study right now, so I am relying on my vast army of bored commenters to do the work for me.)
Oh thank god.
/diet mt. dew shakes finally stop
I doubt it's junk science. I've never seen a thin person drinking diet soda, and I've never seen a fat person get thinner after drinking diet soda.
CE: Who are you calling fat? 😉
Sounds conclusive to me.
I know thin people who drink diet soda.
Maybe fat people get and stay fat because of the other things in their diet?
NONSENSE!! EVERYONE KNOWS EVERYTHING IS SODA'S FAULT
I lost a lot of weight drinking an absurd amount of diet soda. In fairness, it's unlikely that you saw me do it, so your point stands.
My step son stopped drinking soda altogether and lost 60 lbs without making any other changes in diet or activity.
He was working in fast food and the employees had free soda which he drank constantly all day long.
My guess is that if he had switched to diet soda it would have had the same effect.
Yeah, I know... extreme case. Aside from that one example I have never seen it either.
Really? I lost 30 pounds in six weeks after switching from regular Coke to Diet Coke. No other diet or exercise changes.
Mind you, I was swilling the stuff to the tune of 3 liters a day.
Dr. Bloom is ignoring the prime function of the study: To confirm an agenda.
Deniers! Deniers everywhere!
Wait, what? You mean to say that you have less credulous blogs? Is that even possible?
Yuk-yuk-yuk!
What if it's a mind/body interaction? Your mind interprets X as sweet, and the gut bacteria react to that response, not to the particular chemical. Similar to the way our minds react to different things we find fearful, and then our bodies react to that perception.
Just a thought.
You know who else responded to something sweet?
Tony the Tiger?
SugarFree?
Your mother?
How do you convince a mouse a placebo tastes sweet?
Use sugar?
How would the gut bacteria respond to a chemical pathway between the brain and the tongue?
I'm just speculating, but a response in the brain could (possibly through intermediate steps) cause a change in gut chemistry.
Telepathic bacteria. Duh.
I'm thinking of it this way. Imagine that you smell something totally revolting, and you get nauseous. That's your gut responding to a signal going from your nose to your brain. The same reaction might happen with entirely different chemicals. So, couldn't a tongue-to-brain signal that's the same, despite being caused by different chemicals, cause the same reaction in the gut?
Maybe the gut bacteria are being "fooled" the same way your tongue is: "OK, we're getting that sugar signal from the brain! You know what to do!"
Gut bacteria don't get a signal from the brain; they're not neurally connected.
There could be some sort of change in the chemistry of the gut due to the brain's perception, but we're talking epicycles within epicycles at this point. And there's still the issue of why other substances perceived as sweet don't produce the same reaction.
It's not an epicycle to point out that the brain has some control over the functioning of the gut, where the bacteria live. It's not just a metaphor to say that your guts feel different if you are scared or in love. That's hormone (etc.) flow created by your brain. It seems reasonable to assume that gut bacteria will sense and possibly react to such changes in their environment.
I've heard of other studies suggesting that an insulin reaction happens when people ingest artificial sweeteners, which seems more plausible. I'd like to see a much larger study before giving much credence to this.
If it's the same study I read regarding sucralose, the test subjects were obese people who switched from regular sodas to diet sodas. Most of them had insulin spikes after injesting the soda, which isn't that bad of a thing, really.
I have two quibbles with Dr. Bloom's response:
The failure to propose a mechanism to explain particular observations doesn't automatically invalidate those observations. Newton's law of gravitation wasn't invalid just because it lacks a mechanism to explain what causes gravity.
The fact the chemicals all bind to the same receptor on the tongue implies there is some structural or chemical commonality.
Re: Stormy Dragon,
Newton's Law of Gravity is not meant to explain what gravity is, only how it works for two (or more) masses.
Maybe, but that does not mean the chemicals do the same thing, only that their structure (which triggers the receptor) is similar:
Most likely, the people performing the study are witnessing a phenomenon that is not related to the sweeteners at all.
I agree with Dr. Bloom that's there are problems with the experimental design of the Nature study. What I don't agree with is his blanket assertion that it is a priori impossible for artificial sweeteners to have an impact on microrganisms. That's an ideological statement, not a scientific one.
Holy shit. They only tested 7 humans, 4 of which showed a response...and that gets into Nature? Holy fuck.
I am with Stormy here. See my hypothesis above.
Again, possible, it could be incorrect, but the assertion that there are no common molecular features among the tested molecules is clearly wrong and not a good argument for discounting the paper.
Chemists should know enough to ask questions of biologists before popping off about molecule-cell interactions. I'm painfully aware of this because I found myself in a completely unfamiliar area when I did my last set of research. Fortunately, the biologists I worked with were very patient in explaining things, and I did my best to return the favor.
The thing is, their structures are NOT similar.
If there's absolutely no similarities, what distinguishes sweet tasting molecules from not sweet tasting molecules? Some sort of ineffable "molecule soul" that determines its sweet/non-sweet nature in a manner completely unrelated to the physical nature of the chemical?
Well, go look at the structures of sucralose, saccharine, and aspartame and you tell me.
ACS&H is an out and out fraud.
The organization and related entities like Quackbusters have been and continue to be run by some comic book thoroughly corrupt characters the likes of which have included Beth Whalen, Stephen Barrett, Bobby Baratz (who forged the name of a patient in a matter in which I was involved) and Gilbert Ross.
Barrett and Ross have both lost their medical licenses in the past. Ross was convicted of participating in a Medicaid fraud scheme and spent some time at club fed.
ACS&H has long been funded by the likes of Monsanto, Dow Chemical and many other multi-national crony capitalists.
Moreover, according to the BBB, ACS&H does not meet the BBB's standards for accountability for non-profits.
ACS&H's Board of Trustees has consistently been dominated by folks with direct connections to the bio-tech, pesticide, vaccine and the heavily subsidized junk food related industries that have milked the productive classes out of hundreds of billions of dollars through the years.
Of course, Bailey does not discuss these things.
Perhaps Bailey should check out Tim Bolen who has spent years exposing the crackpots, like Barrett and Victor Herbert and Bobby Baratz, and kicking their ass in court in cases such as the California "consumer protection" action brought by ACS&H against King Bio.
It was ACH&S that sought to put King Bio out of business and it did not hesitate to look to the courts to effect its objective of cleansing the marketplace of makers, marketers and practitioners of alternative health products and modalities.
Thus, ACS&H chose to use the courts to eliminate health freedom for you and me. It claimed that King Bio's ads for certain homeopathic products were false and misleading.
Both the trial court and the appeals court concluded that ACS&H's "experts", Barrett and Wallace Sampson were, inter alia, biased, unqualified to opine on the clinical trials of homeopathic drugs, and that their testimony "should be accorded little, if any, credibility".
Funny, have I missed Bailey's coverage of these matters.
I don't know enough to comment on what your rambling on about, except for this: homeopathy is bogus, bogus, bogus.
Homeopathy
If sweetness alone is the common factor in their chemical structure, and contribute to the noted effect in the paper, then the same effect should be attributed to sugar as well.
I'm pretty sure eating sugar raises blood sugar levels.
Now you're just shilling for Big Insulin
Lead tastes sweet, and has been used as a sweetener in the past. However, you'll notice that it has completely different physiological effects than sugar.
Oh...!
(Shakily lowers spoonful of lead paint chips)
So does automatic transmission fluid. Again, completely different effects.
If Newton were saying that only apples, cows, pianos, and snowflakes were affected by gravity, then that would be a good analogy.
The fact the chemicals all bind to the same receptor on the tongue implies there is some structural or chemical commonality.
No, it doesn't. Most animals don't sense aspartame as sweet, for instance -- it's a pure accident that humans, apes, and old world monkeys do.
Even if it is accidental, there's still some similarity there. That's how the receptor works. Whether or not the particular similarities human taste receptors depend on have any significance remains to be seen, but they still exists.
The same accidental structure affects gut bacteria and human tongues, but not new world monkey tongues? Implausible.
As a number of people have already said, this looks like a bad experiment, but Dr. Bloom's claim there's no chemical or structural similarities among sweet molecules is equally ridiculous.
There are obvious structural similarities between sucralose and sucrose because one is made from the other, but sucralose, sucrose, glucose, or any other sugar really has no structural similarity to saccharine or aspartame.
No it isn't. The ability to bind a particular receptor is a tertiary feature and is not directly related to the other chemical properties of a molecule.
For instance, antibodies have a binding site at one end that will bind to its target epitope. So you can make antibodies that bind to cell surface proteins, including taste receptors. An antibody is an enormous protein, having nothing at all in common with fructose, yet one could select an antibody that has the same effect on taste as fructose - a small simple sugar molecule C6H12O6. Antibodies by contrast consist of thousands of atoms and include lots of other elements, particularly nitrogen for those amine bonds. The way they are processed by the body follows entirely separate metabolic pathways.
Prior plausibility is important when positing a new phenomenon. It doesn't invalidate the results, but it does raise a flag that says one should be skeptical and look for a robust, well controlled study with well defined end points.
I've lost about 11 lbs over the past month by cutting (except for the occasional cheat meal) carbs. I still drink a lot of diet soda, which might be why I haven't lost more weight. I'm hoping the study is bogus, and that there's no connection between artificial sweeteners and blood sugar levels, because I drink that stuff all the time.
Black coffee my friend, preferably from a stained mug. More boost, and you'll look a little bad ass.
Disclaimer: I drink only black coffee, and I use a red Angry Birds mug. (to remind people that it doubles as a projectile)
I like black coffee, and that'd be a good alternative, but the coffee my office serves for free tastes like sewage. Numerous complaints have fallen on deaf ears. The free diet mountain dew tastes great though.
After a while you get used to the sewagy taste of cheap coffee.
And diet mountain dew tastes like funky ass.
Cheap coffee is useful as a means of mortification of the flesh. It quickens the thoughts, propels the body, and blunts the fear of death.
Pretty much. Retaining the ability to scoff at mortals is what life is all about.
Three key ingredients for a long and happy life: Caffeine, Nicotine and Velveeta!
If the molecule causes a "sweet" sensation, then it has a particular molecular feature (or features) that allow it to bind to a particular taste receptor. Is it entirely non-plausible that those common features might cause a common set of responses in bacteria? Does a chemist know exactly what sort of receptors "gut" bacteria have and how ligands bind to them? Could a chemist look at, for example, decamethylcyclopentasiloxane (D5) and estradiol and discern, by eye, why they both bind to estrogen receptors?
The paper may indeed be incorrect, but "argument from personal incredulity" is a logical fallacy.
Looks like stormy said much the same thing while I was writing.
Agree completely. If the ACSH guy had said, I performed their experiment and was unable to replicate the results, then that would be a proper scientific rebuttal. This is just a naked appeal to authority (his own). What if he had tried to replicate the experiment and actually came up with the same results? Dear gods he might be led into a line of research that revealed heretofore unknown chemical and/or biological mechanisms...can't have that!
Is it entirely non-plausible that those common features might cause a common set of responses in bacteria?
Yes. Most animals, including new world monkeys, don't sense aspartame, for example, as sweet, so it would be quite odd for random bacteria to do so.
I, uh....What the hell is this? No one with an iota of scientific literacy could concoct that nonsense. It is homeopathy-level ignorance.
I looked to see who did the study, wrote the article. I got Jotham Suez, Department of Immunology, Weizmann Institute of Science, Rehovot 76100, Israel. Ok, something is amiss...so I look at the Weizmann Institute site and get:
"On the Weizmann Institute campus in Rehovot, Israel, around 2,700 scientists, graduate students, highly skilled research technicians, and the staff who support them come to work every day with the goal of solving the most challenging problems facing humankind: global warming,......."
Ok, I stopped right there.
The article someone linked to this morning had a quote along the lines (channeling NDT here) of something like "we don't know what all this unsupervised drinking of artificial sweeteners will do."
"Unsupervised?" Give me a break.
I don't necessarily believe the paper, but I wouldn't call it impossible or "homeopathy level ignorance." I would modestly claim some small level of scientific literacy.
And, who the hell is approving articles for publication at Nature? Have they gone the way of Scientific American?
What political activists don't understand is that if they 'take over' science, it won't be science anymore, just a cargo cult.
This is what pisses me off so bad about the global warming scam. It is destroying the credibility of science in the mind of the public, which was tenuous at best to begin with.
Nature papers have to go through 3 independent referees, plus the editor. And did you read the study? Because if not, discounting it based on the affiliation of the author is just silly.
I'm questioning it because they based their study on a sample size of 7, only 4 of which were confirmative cases.
That does raise some red flags. But they also saw it in mice, right? How many mice were in the study? It's possible that was the main focus, and then they also had a small number of human subjects and saw a result that was suggestive but needing a larger sample. I don't know, haven't read the paper.
And for the record, I'm not well informed enough to have a strong opinion on this one way or the other. But as a rule of thumb I tend to be very skeptical of studies on diet and health.
That's really silly. I wouldn't discount it just based on the fact that there are climate scientist there. Scientific institutes put out PR just like everyone else and saying "we work on global warming" is good PR.
OT: Where are they Now? 80s Cartoon Stars.
http://vimeo.com/105847954
Jessica Rabbit is the tie in. Steve Cutts is pretty funny.
The only plausible theory I can think of is that somehow your gut bacteria can "taste" sweetness too. Smell/taste receptors are very primitive and use the same chemical pathways as neurons, so I wouldn't be surprised if bacteria can "taste". So maybe for some reason the gut bacteria "smell" the artificial sweeteners and then try to consume them for energy, but can't and so die.
They might not have to respond directly to the artificial sweeteners at all.
What if replacing too much real sugar simply means the bacteria don't have enough nutrition to maintain a 'healthy' population level and this disrupts the process.
Even new world monkeys don't "taste" aspartame as sweet -- highly unlikely that bacteria would.
When it comes to bacteria "taste" is really more a matter of "does this molecule activate a receptor on this cell" , it's anyone guess as to whether aspartame does that.
It's possible that the non-responders were people with gut bacteria that didn't and the responders were people with gut bacteria that did.
I'm skeptical of these types of studies, too, but the this Bloom fellow is basically arguing from ignorance: he doesn't know how to explain these results so they must be bogus. That isn't very convincing, either.
It's not an argument from ignorance to demand a higher standard of proof for studies with incredibly counterintuitive claims.
All the discussion of beverages made me thirsty. I made a white russian. Does that count as a diet drink?
What some are missing here is that taste buds are activated by molecular structures. Vast numbers of molecules have similar structure yet widely varying characteristics. Large numbers of molecules have similar structure yet taste very different. Ethylene glycol tastes sweet, cellulose does not.
Dr. Bloom is correct. Lumping molecules together based on taste or color is nonsense. Chemical phrenology.
They have in common that there's at least one set of receptors they bind to. There may be more. Why is that difficult for you to understand?
They are not binding.
If they activate a taste receptor, then yes, they are.
It has been a long time since I looked at any of that, but that is how I remembered it.
I was correct. Taste receptor cells are activated in an enzyme like fashion to release stored Ca+2 internally which then activates neurotransmitters.
There is no chemical binding between the receptor cells and the activating compound.
http://www.jbc.org/content/277/1/1.full
Additionally, this bogus study is easy enough to replicate. However, the study itself is no doubt a replication of many many other studies done on the three sweeteners by the companies that market them, by the FDA etc. All we have to do is go back and look at those studies. I am confident that neither aspartame, sucralose, nor saccharine elevate blood sugar.
In any case, there is not point in arguing it. All we have to do is replicate the study.
Enzymes chemically bind to their substrates. That's how enzymes work:
Receptor binding is not the same thing as chemical bonding. With the receptors I was working with (not taste!), the ligands' shape and the polarity/polarizability of specific sections caused activation of the receptor via a conformation change and "pairing off" with another receptor.
The result was not terribly different than a glove closing on a baseball.
Old man is correct. However, a receptor need not bind its specific target to be activated. A receptor might not even be bound in its target site.
Activation is usually a conformational change that causes a change to the shape of the other end of the receptor, resulting in a phosphorylation or an ion channel opening, etc. Other molecules might stick to the side of the receptor in such a way as to cause activation - or block activation. So from a physiological point of view a "sweet" molecule need not have anything whatever in common with a nonsweet molecule.
The connection between our gut microbiome and our health is a brand new area of inquiry and is very poorly understood at this point. Most of the papers coming out on the topic are at the level of "look at what I found", because even figuring out who all the players are is beyond our current state of the art. Many of the microbes in your gut cannot even be cultured in a lab at this point. It is an amazing area of inquiry, but there are going to be lots of dead ends and false starts when opening a new field of study.
OH. I used the cellulose/Ethylene glycol examples because cellulose is a sugar and very similar in structure to sucrose. Ethylene glycol is an alcohol, structurally not similar to sucrose.
Really? Those hydroxyls aren't a common feature?Their similarity in OH-OH distance isn't a common feature? Of course there's structural similarities which is why they're both perceived as sweet.
You are correct, they are.
Texas sharpshooter fallacy. There are scads of chemicals with hydroxyl groups and most of them aren't perceived as sweet.
Note the other part- hydroxyl distance. The hydroxyls are necessary-but-not-sufficient. The molecule also has to have the right geometry of the "keys" and be able to fit the receptor.
Again, I'm not saying that the Nature paper's authors are correct or not, I'm just pointing out that there's nothing there that's crazy-wacky for the reasons Ron is citing.
Clarification: the *presence* of hydroxyls is necessary-but-not-yadda-yadda. The key is their distance and conformation.
You are correct on that.
BTW, you should understand why cellulose isn't perceived as sweet. Trying to fit a high molecular weight polymer into that receptor is unphysical.
this just proves my theory that white powders in paper envelopes boost blood glucose levels.
And make you happy.
Isn't this really just an industry front group? Maybe they're right. Maybe they're wrong, but because of their funding, anything they say is clouded by that.
Isnt calling everything "an industry front group" just a bullshit way for Precautionary Principle Douchebags to advance an anti-scientific, 'feelgood' agenda?
When you get most of your funding from the very corporations that you are defending, then you are an industry front group.
I am an idiot. I was going back and forth with Old Man with Candy, not realizing he is just a shill for big sugar. I mean, goddamn, it's right there in his name.
Aren't the folks who did the original study a government front group?
Why is a scientific study funded by a business automatically suspect, but one funded by the government, that's going to be used as the justification for more government control, must automatically be considered rigorous and infallible?
Hush now, son! You'll ruin the narrative.
In this case, this study, what does the government of Israel have to gain from it?
And I never said this study was infallible. In fact, at first glance at least, it looks poorly done, and it has little credibility to me. But that doesn't mean I automatically side with this industry front group (sorry but that's what it is).
Imagine my surprise when ctrl-F "allopathy" returned no results.
Did the studies find similar results for different sweeteners? If so, what's the point of saying the results don't make sense? It may have nothing to do with the fact those substances all taste sweet. So what?
OFF TOPIC RANT!!!
One of the dumbest things about the scientific community is that they hide scientific publications behind a paywall.
Nobody gets paid for writing scientific papers! Not nobody gets paid to peer review papers either! They write papers to get published so that they can impress their superiors.
The fact that scientific papers are universally hidden behind paywalls means that it is IMPOSSIBLE for the public to assess the methodology of the papers and judge for themselves.
Peer reviewed scientific journals hide their information behind paywalls, while advocacy websites by anti-GMO lunatics are free to the public. Here, read my propaganda! It's FREE!!!!
The result is that the general public is exposed to a wealth of junk science by advocacy groups, yet the scientific community makes it DELIBERATELY IMPOSSIBLE for the public to get access to peer reviewed publications for comparison. They have to rely on second hand sources like journalists to be unbiased in their reporting.
Now in this case, ACSH the advocacy group may be right. But HOW Am I SUPPOSED TO FIGURE THAT OUT if I don't want to pay $3.99 to view a copy of the article for 24 hours on their stupid pay site.
I'm no socialist who thinks everything should be done for free, but if scientists want to have more public influence than hacks and cranks, they need to make it just as easy for the general public to read actual scientific publications as it is to read hack advocacy websites.
So where is the distortion which results in the mess? Outside of the fact that sites will print garbage from anti-vacs, UFO bleevers, etc just for the clicks...
The scientists want their publications to be free to the public as well. You need to bring this up with the journal publishers.
There is a big movement afoot to address this. Getting proper peer review and refereeing in place is the tough bit. Somebody needs to pay for the editorial process.
PLOS is an attempt to address this problem.
I think the problem might be that the top journals like Nature actually make a lot of money, and there's an institutional inertia in terms of scientists wanting to publish in the big journals.
It doesn't work to start new journals, if you can't get the big, high-impact-factor journals to open up access to the public.
The peer review and refereeing - I wonder why that can't be done via some sort of wiki-like system.
Maybe there should be a paywall system for non-peer reviewed papers that anyone behind the paywall can look at, peer review, crituque, and so forth in a wiki-like fashion, but the public only sees the paper once is it past peer review and has been published.
That way the people who pay for the subscription can see pre-publication papers, so they get to hear about new research before it is publicized.
Good scientists don't do science in order to have "public influence". They also don't expect you to, or want you to make rapid and unfounded changes to your life based on the result of a few studies that need lots of replication and validation.
Furthermore, most of those articles are available for free in libraries. And they usually become available as online PDFs fairly soon. You can also request a copy from the authors.
Having said that, most scientists are also bitterly complaining about the high cost of journals and would like those articles to be free, not so much for your benefit, but for academia and students. And it's happening (slowly).
my co-worker's sister makes $75 every hour on the computer . She has been without a job for 5 months but last month her payment was $17504 just working on the computer for a few hours. This Site....
???????? http://www.netjob70.com
And for the record, I'm not well informed enough to have a strong opinion on this one way or the other. But as a rule of thumb I tend to be very skeptical of studies on diet and health.
I tend to be very skeptical of "scientific" studies that make no fucking sense, such as saying that ingesting chemicals with zero calories will make you fat, when the physics is unambiguous: If calories consumed are less than calories burned over time, you Will. Lose. Weight. Doesn't matter what the fuck you eat.
Yes, some substances may make you hungrier than others, and working out daily will ramp up your bodies' burn rate, but it always come down to fuel intake versus burn rate, whether it is a car or a human body or a bonfire.
"What the fuck you eat" matters a great deal because it affects satiety; that is, it affects when your body tells you to stop eating.
So while it doesn't matter what you eat given that you eat 1000 calories that's the wrong thing to look at. What matters is that if you eat one kind of food, you stop after consuming 800 calories, and if you eat another kind of food, you stop after consuming 1200 calories.
What the fuck you eat absolutely matters, because the "calories in-minus calories out" only works at the level of the fat cell not at the whole organism level. Fat cells are storage devices. In the presence of insulin (insulin being the controlling hormone for fat cells), the cell stores excess calories. As long as there is insulin present, it is biochemically impossible for the fat cell to release calories. In order for fat cells to release their stores your diet must not produce an insulin reaction. It is possible to eat a highly calorie restricted diet and still not lose an ounce of fat because of the nature of what you eat. Incidentally, if you take a very fat person, put them on a high carb calorie restricted diet, you run the risk of killing them. They are not getting enough calories to run their body yet their fat cells are unable to release their stored energy, so the fat person's body starts cannibalizing the protein in muscle structures for energy and eventually: fat person dead of heart attack.
I have my doubts about whether the results of this study are true, but it's not completely unreasonable. Mammals produce gastric secretions in response to taste and smell, and that can affect gut microbes.
If you taste something sweet, your body gears up for processing sugar. If it subsequently doesn't get any sugar, that might have negative effects.
I used to use a ridiculous amount of aspartame packets (mostly in my coffee)... it certainly did have an effect on blood glucose - but that was from the carb content of the fillers (dextrose, maltodextrin).
I switched to pure stevia extract (NOT branded and packaged). No fillers, no carbs, and a glycemic index of... zero.
I still swill the diet soda, though.
I laughed.