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Root cause of Alzheimer's may be fat buildup in brain cells, research suggests

medicalxpress.com

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Re: Root cause of Alzheimer's may be fat buildup in brain cells, research suggests

#171

Post by cassepipe »

ggm wrote: post #102
iforgotpassword wrote: post #90

Earlier quoted context omitted.

Honest question: how? I've never seen anyone who's obese and having a diet that made me go "huh that's odd how can they be obese?" While the inverse occasionally has been true, generally people who I consider in good shape appear to eat less, and less greasy food. So while there might be exceptions it seems to be a damn good rule of thumb to me.

Because of homeostasis: dissolved substances like fats in the bloodstream are regulated within bands, and beyond certain limits the amount ingested doesn't translate to more: it's excreted or winds up elsewhere. Your metabolism may cause states worse than other people, sure. But that pound of butter you ingested isn't directly causing rises in the bloodstream to infinity. It's long-term accumulated burden and excess…

While I always knew that sugars where the main culprit for body fat thanks to a highschool biology class, I have never understood why fat is less of a problem so thank you. Could you link me with sources or search keyword in order to know more of what the body is doing with excess fat ?

Re: Root cause of Alzheimer's may be fat buildup in brain cells, research suggests

#172

Post by cassepipe »

zamalek wrote: post #132
iforgotpassword wrote: post #90

Earlier quoted context omitted.

Honest question: how? I've never seen anyone who's obese and having a diet that made me go "huh that's odd how can they be obese?" While the inverse occasionally has been true, generally people who I consider in good shape appear to eat less, and less greasy food. So while there might be exceptions it seems to be a damn good rule of thumb to me.

> I've never seen anyone who's obese and having a diet that made me go "huh that's odd how can they be obese?" Are they eating fat _or sugar?_ The body will aggressively squirrel away any unused sugar as fat. As one example, a Big Mac contains 7g of _added_ sugar. Fries? Coated in dextrose. Sugar is added to damn-near everything.

Where I live, there's only one beer brand that does not have glucose syrup. Sad.

Re: Root cause of Alzheimer's may be fat buildup in brain cells, research suggests

#173

Post by antiframe »

_heimdall wrote: post #150
caymanjim wrote: post #72

Earlier quoted context omitted.

The idea that eating fat leads to higher body fat is the most dangerously-wrong health misconception in history.

We've probably done more harm with the similar, and also incorrect, assumption that eating more saturated fats go directly to the blood and clog arteries.

Can you point to some evidence that increased saturated fat consumption does not increase LDL? Or that there is no link between serum LDL levels and plaque build up? Or are you making a different claim?

Re: Root cause of Alzheimer's may be fat buildup in brain cells, research suggests

#175

Post by loceng »

ProjectArcturis wrote: post #21

As a former Alzheimer's researcher, this is a big fucking deal. It puts together a lot of clues (APOE risk, microglia) and finds a theory that makes a lot of sense. All around the world, there are labs pulling late nights trying to figure out how to drug this.

Do you know if water-only fasting is a good way and/or necessary way to help stave off or even allow regression to occur?

An anti-inflammatory diet, inflammation being known as one of the ~5 root causes of Alzheimer's for awhile now, like a ketogenic diet has been known to be beneficial - but water fasting will not only lower inflammation as much as possible, it will also arguably would cause more of the fat reserves to be used up - but whether that includes fat buildup in the brain too?

Re: Root cause of Alzheimer's may be fat buildup in brain cells, research suggests

#176

Post by ianai »

pama wrote: post #164
ianai wrote: post #40

Earlier quoted context omitted.

What kind of fat is it? Like is it possible to avoid by avoiding too much fat?

Per the Nature paper, this fat is believed to be part of an immune system response and not related to your intake or total body fat. It is also far from clear that eliminating the production or use of this fat during a microbe invasion would lead to more or less dementia down the road (a good reminder that clinical trials are useful and also risky). This work shows a very refreshing and solid hypothesis and lots of p…

Yeah, I almost wish I hadn’t asked given the comments. Really points at an interesting mechanism though. Hopefully this means some kind of preventative or even treatment is possible.

Re: Root cause of Alzheimer's may be fat buildup in brain cells, research suggests

#177

Post by spudlyo »

crakenzak wrote: post #107
spudlyo wrote: post #34

Earlier quoted context omitted.

Fasting seems like a solution because in the fasted state your body doesn't need to produce insulin. Your body needs insulin to push fat into cells. Your pancreas gets a break, and perhaps sensitivity improves when you go on an extended insulin-free holiday.

The insulin protein promotes glucose (not fats) uptake into the muscles (~75%), liver (~15%), and other tissue (~10%) to aggressively lower blood sugar levels back to a total circulating amount of ~5g.

In the obese, glucose is preferentially directed to adipose tissue for storage as fat. This is due to both insulin resistance, and to the limited storage capacity in muscles and the liver for glucose in the form of glycogen. I was writing colloquially and intentionally left out details like lipogenesis, which in retrospect probably wasn't a great idea.

Re: Root cause of Alzheimer's may be fat buildup in brain cells, research suggests

#178

Post by spudlyo »

joshuahaglund wrote: post #75
spudlyo wrote: post #34

Earlier quoted context omitted.

Fasting seems like a solution because in the fasted state your body doesn't need to produce insulin. Your body needs insulin to push fat into cells. Your pancreas gets a break, and perhaps sensitivity improves when you go on an extended insulin-free holiday.

I'm no biologist but it's my understanding that insulin causes cells take up glucose, not fats. And I don't see anyone suggesting insulin or the pancreas is involved in any of this. So what does the pancreas have to do with Alzheimers?

It depends what cells we're talking about. Thanks to insulin, glucose can be stored in the liver and muscle tissues as glycogen. In folks with poor insulin sensitivity these cells do not respond as effectively to insulin, and their uptake and storage is reduced, leaving more glucose in the bloodstream. In the obese, it's also likely the liver and muscle tissue glycogen stores are near max capacity. In this case insulin facilitates the uptake of glucose into adipose (fat) tissue through a process known as lipogenesis. When I wrote "insulin pushes fat into cells" that's what I meant.

Re: Root cause of Alzheimer's may be fat buildup in brain cells, research suggests

#179

Post by striking »

VMG wrote: post #163
striking wrote: post #161

Earlier quoted context omitted.

> While we did not find statistically significant evidence to support an association of consuming relatively more plant- and fewer animal-based foods with the risk of dementia, our HR of 0.93 (95% CI: 0.86–1.01) for the hPDI cannot rule out a subtle beneficial effect of healthy plant-based eating on the brain. "cannot rule out a subtle effect". Otherwise not statistically significant. Great.

it doesn't seem like plant food causes Alzheimer though

Oh, yeah. Sorry, that makes sense.

Re: Root cause of Alzheimer's may be fat buildup in brain cells, research suggests

#180

Post by amanaplanacanal »

callmeal wrote: post #121
brettv2 wrote: post #101

Earlier quoted context omitted.

> I've never seen anyone who's obese and having a diet that made me go "huh that's odd how can they be obese?" Your question isn't refuting OPs claim: the people you are observing to be fat are fat because of their carb/sugar intake, not fat. i.e. if you just fed someone large amounts of protein and fat they would be lean; it is the sugar and carbs that make them fat.

> if you just fed someone large amounts of protein and fat they would be lean; A large amount of protein would make them fat - experiments have shown that about 8% of ingested protein gets converted to glucose in the liver: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3636610/ The authors calculated that ∼18 g (79%) of the 23 g of ingested protein could be accounted for by deamination; thus those carbon skeletons wer…

I think you misread that experiment. It appears that some quantity of protein was converted to glucose, but that it wasn’t dependent in the quantity of protein consumed.
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