The acid/alkaline theory you're talking about is indeed pseudoscience at best.
I'm talking about the "acid/alkaline diet" or "alkalinize or diet" especially the ones with charts and theories about changing the ph of the stomach.
What I'm talking about is mineral loss and mineral retainance caused by the body trying to maintain a balance which if not maintained would kill the body.
Yes the truth that those new-age theories about acid/alkaline don't tell is that small changes in the acidity of the body would kill you very soon as many body functions can only work at a certain body ph and this nothing but a fact. That's why the body tries at all cost to maintain the acidity or alkalinity that tissues require to function. That's why there's actually no change, the body has a mechanism to avoid this. This mechanism increases the loss of minerals and minerals are a major aspect of health since they're required for the most important body processes and functions. So it's a matter of how certain foods affect the mineral losses. For example foods rich in sodium increase mineral losses and so on.
If you look at pubmed you will see there's a pletora of published studies and researchers on this subjects and compared to the amount of scientific evidence there's about lectins effect this is almost a gospel truth.
This doesn't mean of course that the various new-age alkaline/acidic food charts, you're slightly acidic so goes and drink a glass of coral calcium, are not scientific. But the acid and alkaline terms are surrounded by confusion and the scientifically proved concept of increased mineral losses shouldn't be confused with Cooper or other diets.

btw: once one forgets about the pseudoscientific concept of acid and alkaline and understands how the proved concept of increased mineral losses is all about what it has got to do with acid and alkaline, one will also see that Dr Cordain is talking about the scientifical one supported by a pletora of rigorous studies and not the new-age sci-fi one of Cooper and others

David