I have been taught in school that aluminium is harmful for brain. Thus sour meals should not be cooked in aluminium pots and it is unhealthy to add lemon juice to tea while there is teabag in the cup, as acid facilitates aluminium release.
The only safe limit for aluminium intake I know is FDA pediatric limit for parenteral sources (5 μg/kg bw/day). I know no research the limit is based on, but I have read an abstract of a paper claiming it was impossible to comply with the regulation in patients weighting less than 50 kg.
Nowadays aluminium ions are present in several vaccines, which are considered safe to be injected intramuscularly in infants despite despite being nowhere near the FDA limit.
I'm quite confused how strict should I be in avoidance of aluminium intake (especially dietetary intake - which I expect to be far less effective than parenteral).
[EDIT]
It seems aluminium is also a component of some antacids which are used to treat heartburn. Does it mean aluminium consumption is safe at general, or it is just considered to be less harmful than acid indigestion (there are some side effects mentioned - but nothing about accumulation in the brain)?