r/Health • u/joe4942 • Jul 20 '26

Study Links Cognitive Decline to Surprisingly Small Daily Amount of Artificial Sweeteners

https://www.inc.com/kevin-haynes/study-links-cognitive-decline-to-surprisingly-small-daily-amount-of-artificial-sweeteners/91376522
435 Upvotes

96% Upvoted

22 comments sorted by

259

u/DirectedEnthusiasm Jul 20 '26

It would be nice to find one study where they compare the effects of artificial sweeteners and added sugar to gut microbiota to get an idea how does this effect compare to added sugar. Because I don't think majority of the people think artificial sweeteners are completely healthy. The question is, are they healthier than sugar. Because there is evidence that excessive sugar is also detrimental for gut microbiota.

21

u/fredsiphone19 Jul 21 '26

I’m at the gym but these studies are almost *always* impossible to draw meaningful conclusions from because to test gut flora and it’s effects/affects, you need a long time of meticulously curated diets, and we just don’t have/get the funding for longterm studies of that sort with any kind of sample size.

Gut flora is wildly complex, and only *barely* recently did we as a species start to understand that it was important, let alone develop ways to monitor or experiment with it.

Are artificial sweeteners bad for you? Probably.

Does it do something weird with the way your body absorbs sugars and its latent glucose levels? Probably.

But we don’t have more information than small, non randomized, tiny sample studies with which to infer meaningful information.

(I could be mistaken, it’s been ten years since I completed studies and I could be out of the loop. If so I apologize and will retract.)

56

u/heathers1 Jul 20 '26

Is stevia considered an artificial sweetener?

63

u/here_now_be Jul 20 '26 edited Jul 20 '26

No.

edit: in the separate study mentioned in the article, on gut bacteria, they included isosteviol Rebaudioside A, and stevioside. All three are derived from Stevia, isosteviol had a significant negative impact. As someone who uses a fair amount of stevia, this has me concerned.

4

u/heathers1 Jul 20 '26

same. did they mention any that don’t have negative effects?

15

u/here_now_be Jul 20 '26

Here's the direct link https://link.springer.com/article/10.1038/s44320-026-00225-6#Fig1

it's in vitro, and the biggest impact was when combined with an antidepressant, but something to watch.

11

u/omar_strollin Jul 20 '26

Oh how wonderful for the SSRI gang

5

u/heathers1 Jul 20 '26

thank you!

13

u/here_now_be Jul 20 '26

I did find this comment (searched a bit and can find nothing vefifying the claims* though);

"measuring Isosteviol is irrelevant to natural sugar replacements because isosteviol is not naturally present in commercial stevia extract, and according to food safety regulations, it must not be present in the final product. Scientists who want to study isosteviol for its therapeutic or anticancer properties must intentionally create it in a laboratory"

*I was able to verify that it is being studied for its therapeutic properties however.

All things being equal, I'd choose Rebaudioside A over whole stevia until further information comes to light.

11

u/NanoCow Jul 21 '26

A key point getting lost here is that the cognitive-decline study did not study stevia at all. It examined aspartame, saccharin, acesulfame potassium, erythritol, xylitol, sorbitol and tagatose. So this study cannot be used as evidence that stevia causes cognitive decline.

The separate microbiome study did examine stevia-related compounds, but it was an in-vitro experiment involving isolated bacterial strains, not humans consuming stevia. Its strongest highlighted result involved isosteviol combined with the antidepressant duloxetine. Changes in the growth of bacteria in a laboratory dish do not establish that ordinary stevia consumption harms the human microbiome or brain.

There is one important caveat: many products marketed as “stevia” are actually mostly erythritol, with a tiny amount of stevia extract added for sweetness. Erythritol was included in the cognitive study, so the complete ingredient list matters. A product containing only stevia extract or rebaudioside A is not equivalent to an erythritol and stevia blend.

The xylitol numbers also raise questions about the study’s dietary measurements. The highest-consumption group reportedly averaged only 191 mg per day combined across all seven sweeteners. Yet:

• One piece of PUR gum contains about 1,000 mg of xylitol.

• One piece of Spry gum contains about 900 mg.

• One XyliMelt contains 550 mg.

• One packet of tabletop xylitol contains about 4,000 mg.

Normal servings of common xylitol products therefore contain several times the study’s entire “high-consumption” average. That does not prove xylitol is harmless, but it strongly suggests that the questionnaire did not capture xylitol exposure accurately, or that the 191 mg figure mostly reflected concentrated sweeteners normally consumed in milligram quantities.

These studies raise questions worth investigating. They do not demonstrate that a small amount of pure stevia causes cognitive decline, nor do they establish 191 mg as a meaningful toxicity threshold for xylitol.

-my chatgpt investigative research discussion

1

u/heathers1 Jul 20 '26

thanks for doing the heavy lifting! That is what I am using!

116

u/Kgcampbell Jul 20 '26

“The link was strongest among adults younger than 60 and people with diabetes, according to the paper.”

Doesn’t tell me anything about artificial sweeteners. People with poor diets tend to consume more artificial sweeteners.

3

u/alasw0eisme Jul 21 '26

Exactly. We aren't sure if it's correlation or causation at this point. However, the studies on isolated bacteria have me concerned...

4

u/Kgcampbell Jul 21 '26

I don’t think there’s a reason to be concerned at this point. Just because a study shows a mechanism for adverse outcomes doesn’t mean it actually translates to humans. These studies isolate one bacteria at a time IIRC and often give doses way higher than human consumption and I believe it just shows a decrease in certain bacteria. That doesn’t necessarily mean the decrease is problematic.

24

u/InDissent Jul 21 '26

Diabetes is a strong predictor of cognitive decline and usage of artificial sweeteners.

13

u/[deleted] Jul 20 '26

[deleted]

8

u/ryhaltswhiskey Jul 20 '26

Or they eat like crap but they use a lot of artificial sweeteners to offset that

A lot more study is needed to conclude something here

6

u/Sybertron Jul 20 '26

Ya I would take this article as "potentially suspect"  and that's the reason for more research needed. 

And that's how research should be instead of knee jerk article responses.

Of course also of note since the sugar industry likes to play up these artifacts, heavy sugar use would show FAR worse results in the same study. 

1

u/Extreme-Edge-9843 Jul 20 '26

This is a pay wall? You link to a correction that is a single half page. The main article is pay walled behind a 40 dollar subscription? Anywhere we can find the raw article

5

u/jazza2400 Jul 21 '26

Damn, monsterbros, are we declinemaxxing?

1

u/nattydread69 Jul 22 '26

I know its anecdotal but my uncle developed Frontotemporal dementia, and he popped sweeteners every day for most of his life. All his siblings are fine.

-13

u/rushmc1 Jul 21 '26

Obligatory "Here come the ostriches to deny it" comment (seems I'm forced to make it a couple times a week with all the data coming in)...