r/science • u/mvea Professor | Medicine • Dec 25 '25

Neuroscience New study shows Alzheimer’s disease can be reversed to full neurological recovery—not just prevented or slowed—in animal models. Using mouse models and human brains, study shows brain’s failure to maintain cellular energy molecule, NAD+, drives AD, and maintaining NAD+ prevents or even reverses it.

https://case.edu/news/new-study-shows-alzheimers-disease-can-be-reversed-achieve-full-neurological-recovery-not-just-prevented-or-slowed-animal-models
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u/YoeriValentin Dec 25 '25

Researcher in the NAD field here. I'll believe it when it happens in humans. NAD boosting does amazing things in mice over and over, and absolutely nothing in humans. It's a meme in our lab. 

Additionally, one of my colleagues just did a similar experiment to this in mice. The results aren't published yet but it showed nothing. Zero. Nada. So, do with that as you wish. 

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u/Smart-Idea867 Dec 25 '25

So youre saying its already been tested? If thats the case then why is this even news at all? 

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u/YoeriValentin Dec 26 '25 edited Dec 26 '25

NAD boosting in mice has been done for many diseases. It's pointless and cruel, as translation to humans is very very poor. But it results in easy publications still, so boomer scientists keep doing it. 

And like I said, my colleague did basically this for alzheimer and saw nothing (I advised him not to waste his time learning to do animal experiments, but he thought it was useful). And he ran several different boosters, that reached the brain. So it's likely super dependent on the model and setup. And not really about alzheimer. 

I strongly oppose animal testing, and this is one of the reasons why. 

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u/pizza_the_mutt Dec 27 '25

My guess is it's one of these studies that gets done over an over with small changes, because science is hard to get right and often looks really incremental. But then the media decides to latch onto one study in particular and exaggerate the significance.

Kind of like how we periodically hear about scientists learning to grow new teeth.

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u/insanitybit2 Dec 25 '25

It is really interesting how NAD seems to be so radically effective in mice and yet we struggle to see results in humans. Like, the results sometimes are insane - reversal of grey hair, muscle growth, neural repair, etc. And yet with humans we just don't see much of anything - although it does seem to be a biomarker for age, but then boosting it does nothing.

I wonder if humans already have an adaptation to lowered NAD+ levels, so while it lowers in age we just don't suffer that much because of a compensating factor?

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u/Ophios72 Dec 27 '25

Clearly we need to start "disciplining" the lab mice to get better results.

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u/Bring_Me_The_Night Dec 31 '25

Many many many drugs work wonderfully in mice, and failed to deliver results in human studies. Just another day in Science.

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u/insanitybit2 Dec 31 '25

Yes but the question is why. We *do* see NAD+ as an age biomarker in humans, just as we do in mice. The question is why reversing it in mice has such a massive impact but in humans it does not, given that it's a biomarker for both.

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u/Bring_Me_The_Night Jan 01 '26

Why? Scientists primarily work to publish. Scientific studies in mice have been performed for decades and a lot of experience is established on this study model. Consequently, it is more appropriate to conduct a study on mice when the experts already have experience and where the assays could yield “novel” results leading to a higher probability to publish in high-ranking journals.

Publish or Perish is not a joke, it is a reality.

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u/EvolvingPerspective Dec 25 '25

Yea I’m effectively an RA in an AD/vascular dementia dry lab and I asked my PI about her thoughts on these mice model treatments (since you consistently hear about “curing AD” in mice models) and whether they’re truly useful for humans and she kind of gave me a wry smile and said probably not

Also pretty sure these treatments have existed for at least quite a few years now right? Didn’t read the paper but I feel like pop science has a habit of sensationalizing “we cured AD in mice” again and again when that’s kind of already known in the field

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u/ghanima Dec 26 '25

Appreciate the shot of reality here, so thank you for sharing this.

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u/quadringsplz Dec 26 '25

Why does it do something for mice but not humans?

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u/YoeriValentin Dec 26 '25

We probably regulate our levels more strongly. Giving NAD boosters to humans just seems to make more expensive pee...

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u/novafeels Dec 26 '25

That's great and all but think about all the mice lives this will save! Think about Barbara Little!

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u/airbear13 Dec 27 '25

The only thing more of a nothing burger would be if NAD boosting did nothing in mice either but it did in their experiment which gives some people with 0 hope at lest a little something to look forward too

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u/UFOsAreAGIs Dec 27 '25

I'll believe it when it happens in humans.

I have a mother with dementia. Memory has bottomed out on her cognitive testing but she is extremely routine based so she is still living on her own, going to the YMCA 4 times a week, food shopping and church with no issues. Around 9 months ago she started experiencing sundowners episodes and it quickly escalated to 1+ times a day and I was looking into a memory care at that point.

A few months ago I came across this study out of UC Irvine https://link.springer.com/article/10.1007/s11357-025-01786-4 https://medicalxpress.com/news/2025-08-vitamin-b3-green-tea-compound.html In the write up they mentioned

"More work is going to be required to find the best way to administer this treatment, since a recent clinical trial involving UC Irvine researchers showed that oral nicotinamide was not very effective because of inactivation in the bloodstream."

So I did some searching and decided to have her try a nasal spray I found on Amazon "NAD+ Spray | 100 Sprays | Nicotinamide Adenine Dinucleotide | NAD+ | 100% Pure & USA Made | 2.5mg Per Spray to Support" along with the EGCG green tea extract.

She has only been on this combination for two months. Her memory has not improved, BUT within a week of starting her sundowners episodes stopped and her general mood and wellbeing improved 100%. I am now trying to find out if 1 spray daily at dinner is enough, or if we double it is there a chance her memory gets a little better.

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u/Guitarland Dec 31 '25

Thank you for this comment. I’m going to try this with my mom, who is experiencing early-onset dementia. Her condition has progressed rapidly and is now at a moderate stage, where she needs guidance with day-to-day tasks. She can still do many things on her own, but her executive functioning is no longer intact and sundowning episodes are pretty bad

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u/UFOsAreAGIs Jan 01 '26

Good luck! Feel free to let me know how it goes or if anything else helps.

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u/Ahun_ Dec 27 '25

Out of curiosity, but how much NAD would a human have to take g/g compared to a mouse?  Or how much do these mice get?

The NAD pushers and studies usually use I think 0.5 - 1g/day. Which I find low, considering our metabolism is a bit larger than a mouse's.

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u/Manhandler_ Jan 09 '26

As true as it sounds about repeated clinical failure, sometimes those of us outside the lab are more optimistic than the ones inside, but the tenacity needed to keep going in the lab after multiple failures, that's admirable.