Interesting link - thanks.

So where does the aluminum in our diet come from? Is it just a mineral that gets passed up the food chain? Do we touch aluminum metal enough to contaminate our food with it?

Relevent sentences from the abstract:

At this rate, about 4 μg of aluminium is absorbed from a single use of ACH on both underarms. This is about 2.5% of the aluminium typically absorbed by the gut from food over the same time period. Therefore, a one-time use of ACH applied to the skin is not a significant contribution to the body burden of aluminium.

I had an Organic Chemistry professor back in like 2001 who swore by the Al link, or at least was very cautious about it and made the lifestyle changes to eliminate all the aluminum cookware she said could leach with the cooking of acidic foods and all. Seemed a pretty easy enough thing to avoid when we went all cast iron and stainless steel. I'm curious what the history to this Al hypothesis is.

Cookware for hiking etc. commonly uses aluminium.