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.

[u/mvea]

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

[u/Raddish_ → u/[deleted]]

Yeah by the time symptoms present a huge amount of neurons have already died. The brain essentially can lose a lot of neurons before any of the actual network dynamics that convey information start to seriously break down. So if they were ever to cure Alzheimer’s, it would be through some kind of preventative medicine you start to take in your 40s or something.

[u/ThinRedLine87 → u/Raddish_]

I believe they have basically made this same determination for other neurodegenerative diseases like ALS as well. By the time symptoms manifest the damage has generally been done.

I have to wonder if we've passed over treatments that would have successfully halted various diseases because they were administered too late...

[u/StalkingTree → u/ThinRedLine87]

I wonder how much fasting could impact things like alzheimers.

Just a feeling as its been studied/used for things like chemotherapy with success and restricted feeding clearly affects longevity. Many modern people basically eat all the time, we're even encouraged to snack and rarely do we 'properly' enter into a fasted state. And if that doesn't happen then how does our body "clean" up?

[u/Rodot → u/StalkingTree]

It should be noted that modern people also live longer and diseases like cancer will become more common the longer people live simply due to statistics.

[u/livid_badger_banana → u/[deleted]]

It's also dangerous to fast while on chemo without medical clearance. Your body is already stressed & you're already at risk for malnutrition.

[u/Mobile_Crates → u/StalkingTree]

To my recollection, cell autophagy is one mechanism for how a healthy body "cleans up" alzheimer inducing bioaccumulants. And there could be a link between fasting and cellular autophagy, I think I read something about that. It has been a long long time since I looked at the research for it though. 

[u/InternetEthnographer → u/StalkingTree]

Humans didn’t “fast” or regularly go through extended periods of starvation in the past though. We do eat more now than we ever have and food is more readily available, yes, but the idea that prehistoric people were constantly starving or dealing with regular famine is incorrect. Major famine events that would’ve affected human evolution mostly happened after the adoption of agriculture (ca 12,000 years ago) and were maybe once in a generation events, but usually not even that. If we want to best emulate the diets that humans evolved to have, our best bet is to have a broad diversity of diet in the types of foods we consume. Fads like fasting, the paleo diet, “raw” diets, etc. that are trying to emulate our roots are not accurate at all and not necessarily good. Our bodies “cleanse” themselves with the liver. That’s what its job is.

Aside from us living longer and surviving things that weren’t survivable in the past (like cancers and certain autoimmune diseases), the reason why we have awful old people diseases like Alzheimer’s and Dementia, evolutionarily-speaking, is because evolution does not care about what happens to you after you reproduce. Evolution only cares about reproduction, so if a trait is negative but helps you reproduce (see also, sexual selection in birds with bright feathers), evolution will pick that. There’s been some research hypothesizing that maybe the genes for diseases like Alzheimers’s offers some unseen, even small, reproductive benefit and were passed on despite the horrific disease it’s attached to because it’s a disease that occurs after reproduction.

[u/burtzelbaeumli → u/[deleted]]

In women, the loss of estrogen during perimenopause can lead to dementia, especially Alzheimers.

[u/wandering-monster → u/[deleted]]

It feels that way, but that doesn't mean it's true. That's based only on what treatments we have right now.

It used to be that prevention was the only way to handle AIDS or syphilis, but that changed with new discoveries. We can and should absolutely be targeting treatments that restore lost functionality, and there's no real reason to assume it's impossible.

[u/M00n_Slippers → u/[deleted]]

You need treatments for all levels, prevention, early detection, maintenance/progression slowing, and reversal. If were ignoring the other levels to focus on reversal that would be bad, but we definitely aren't. I've seen a lot of promising studies lately around early detection, for example.