3 ms·

Bacteria are relatively easy to spot. If Alzheimers sufferers have more of a given bacteria in their brain than non-sufferers, that should have stood out many d

by tabtab 8y ago

Bacteria are relatively easy to spot. If Alzheimers sufferers have more of a given bacteria in their brain than non-sufferers, that should have stood out many decades ago. I'm missing something here.

bluGill 8y ago
I've seen reports of correlation for many years. The problem is working out the chain - there are many other correlations that have been noted for years that don't seem to mean anything though. I floss: it might not help, but so far nobody has suggested how it can hurt.
btilly 8y ago
Recent research suggests that our brains attack bacteria with amyloid beta. The result of a low-level bacterial infection is therefore not a lot of bacteria, but ever growing amounts of amyloid beta plaques. Which are easy to spot. After that, it is a question of what kinds of bacteria attack brains. Until recently, the prevailing theory was that the amyloid beta plaques were themselves the cause of Alzheimers. As a result we spent an insane amount of money developing a variety of drugs that would clear/prevent those plaques. They did reduce the plaques, but did absolutely nothing for the disease. However with virtually all research money devoted to this theory, and all top researchers on record as believing it, alternative theories fought an uphill battle for acceptance. The old theory is still conventional wisdom and a lot of research efforts are focused on it. But there is mounting evidence for the infectious model. The result is a classic paradigm shift in Kuhn's sense of the word where researchers in each paradigm literally speak past the other. Each regarding their theory as proven. To someone who thinks that infectious disease is the problem, the fact that mouth bacteria have been found in the brain, plus a correlation between gum disease and Alzheimer's, is a smoking gun for causation. To someone who thinks that amyloid beta is the problem, it is an interesting correlation but not compelling enough to overturn the prevailing theory.
- tabtab 8y ago
  So you are saying that the actual bacteria found in the brain is relatively small such that it's been hard to tell if and how amyloid beta relates to it.
  - btilly 8y ago
    That, and hard to prove what is causing the brain damage. The amyloid beta deposits are easy to see and therefore to blame. But over time, bacteria can cause a lot of damage even if there aren't many at any given point.

by tabtab 8y ago

Bacteria are relatively easy to spot. If Alzheimers sufferers have more of a given bacteria in their brain than non-sufferers, that should have stood out many decades ago. I'm missing something here.

bluGill 8y ago

I've seen reports of correlation for many years. The problem is working out the chain - there are many other correlations that have been noted for years that don't seem to mean anything though. I floss: it might not help, but so far nobody has suggested how it can hurt.

btilly 8y ago

Recent research suggests that our brains attack bacteria with amyloid beta. The result of a low-level bacterial infection is therefore not a lot of bacteria, but ever growing amounts of amyloid beta plaques. Which are easy to spot. After that, it is a question of what kinds of bacteria attack brains. Until recently, the prevailing theory was that the amyloid beta plaques were themselves the cause of Alzheimers. As a result we spent an insane amount of money developing a variety of drugs that would clear/prevent those plaques. They did reduce the plaques, but did absolutely nothing for the disease. However with virtually all research money devoted to this theory, and all top researchers on record as believing it, alternative theories fought an uphill battle for acceptance. The old theory is still conventional wisdom and a lot of research efforts are focused on it. But there is mounting evidence for the infectious model. The result is a classic paradigm shift in Kuhn's sense of the word where researchers in each paradigm literally speak past the other. Each regarding their theory as proven. To someone who thinks that infectious disease is the problem, the fact that mouth bacteria have been found in the brain, plus a correlation between gum disease and Alzheimer's, is a smoking gun for causation. To someone who thinks that amyloid beta is the problem, it is an interesting correlation but not compelling enough to overturn the prevailing theory.

tabtab 8y ago
So you are saying that the actual bacteria found in the brain is relatively small such that it's been hard to tell if and how amyloid beta relates to it.
- btilly 8y ago
  That, and hard to prove what is causing the brain damage. The amyloid beta deposits are easy to see and therefore to blame. But over time, bacteria can cause a lot of damage even if there aren't many at any given point.