The reason is that some practitioners go by charts based on laboratories analyzes, others by clinical evidence.

By burning a food, that is by breaking it down to its minutes parts, it is possible to analyze its acid and alkaline mineral content.

If a food has a higher content of acid minerals than alkaline ones, it will be declared acidifying, and vice versa.

Depending on the proportions of acid and alkaline minerals, it is also possible to give a figure to express how acidifying/alkalizing a food is in comparison to the others
The question here is: does a food get broken down as minutely during digestion in a human body which is overfed, tired, stressed, sick, … as in a test tube? The answer  of course is no.

That means that the alkaline content of a specific food will not be exploited to its maximum by the body and therefore is not as alkaline as the charts shows. The same is also true for the acidifying foods.

Personally, as other practitioners, I don’t go by charts based on laboratories analyzes, but by clinical evidence, that is observation of the effect of these foods on living persons. It is of course less scientific, but closer to reality.

For example, millet is supposed to alkalize if you follow the charts but in practice it is acidifying therefore I have put it in the list of acidifying foods..