All of this early research, led to suspicion that aluminium from various sources, such as cookware, foods, vaccines and even water, could be linked to Alzheimer’s. However, through continued investigation, research has disproved this early evidence, and aluminium hasn’t since been found to be a direct cause of Alzheimer’s disease.

-- https://www.alzheimersresearchuk.org/news/aluminium-and-alzheimers/

studies have failed to confirm any role for aluminum in causing Alzheimer’s. Almost all scientists today focus on other areas of research, and most experts believe aluminum does not pose any threat.

-- https://www.alz.org/alzheimers-dementia/what-is-alzheimers/causes-and-risk-factors