[Deecart (OP)]

Many studies show that alzheimer is multifactorial.
So like cancer.

But there is no evidence that the symptom (called "Alzheimer") is external to the brain.
We can also suppose that alzheimer is the concequence of "the misuse of ones brain".

To be more explicit.
If you sleep all the day, so you dont use your musculature, it is obvious that your musculature will disapear during time.

Same with the brain abilities.
If someone cant change his mind, and this is what we can call "learning", it is also obvious that if someone dont use his brain usefully this will make the neurones of the brain disapear.
This can be viewed as some physiological adaptation contrary of the actual dogma that say it is some  disease.

Some evidence is that peoples with higher education are likely not to developp Alzheimer.

The benefits of getting a good education may go beyond landing a good job, and continue to pay off long after retirement. Evidence has shown that formal education, like high school and college, may reduce a person’s risk of developing Alzheimer’s.

Research published in 2020 by The Lancet Commission that examined dementia interventions found 7% of worldwide dementia cases could be prevented by increasing early-life education. The study found higher childhood education levels and higher lifelong educational attainment could reduce dementia risk. Exactly how education helps is a mystery, but researchers have several theories.

Never stop learning
The majority of dementia risk studies have examined the benefits of obtaining education early in life. But Okonkwo says some studies have shown that learning new skills and working in jobs that are cognitively complex in mid and late life could also help protect the brain. For example, a 2015 study co-authored by Okonkwo found middle-aged adults who worked in mentally demanding occupations — especially dynamic jobs requiring frequent interaction and socialization with people — had higher cognitive reserve.

https://www.alz.org/news/2021/higher-ed-lower-risk

Where do you stand on the risk scale ?

[Bored chemist]

"Is alzheimer a concequence or a cause ?"
No, it's a surname.
But Alzheimer's disease is a consequence and a cause.
It's a consequence of a buildup of odd proteins in the brain.
It's a cause of people falling and getting hurt.

There are a number of risk factors and also a number of hypotheses about the nature of the condition.Sadly, none of these has yet led to a cure.
While education can  often postpone the symptoms, it can't prevent them, so the analogy with losing muscle tone is not reliable.
People who keep exercising maintain muscle mass, but people who stay educated and informed still get Alzheimer's.

[Deecart (OP)]

It's a consequence of a buildup of odd proteins in the brain.

And you know that the production of the proteins responsible of the death of the cells is not a mechanism used by the brain to delete unused cells ? Or you prefer to think that those proteins are the initial cause of the disease ?

While education can  often postpone the symptoms, it can't prevent them, so the analogy with losing muscle tone is not reliable.

How do you evaluate the effectivness of the "education" ?

People who keep exercising maintain muscle mass, but people who stay educated and informed still get Alzheimer's.

Probably because they think that they stay educated, but in fact the effectivness of the education was bad.

Its like people who try to train their brain using sudoku and other more sophisticated training sessions : The effectivness is almost null.
A brain with good fonctionning sensors (eyes, ears, touch etc) in a natural environment is perhaps what permit to the brain "to remain young".
Repeating the knowlegde you have acquired (the more you have, the more you can learn...because there is less change in the brain...) is not very efffective.