Considered an alkaline by whom? Bangkok contributor Ted? And his credentials are? A website about folk remedies cannot under any circumstances be considered proveable, medical or scientific fact. Sure, apple cider vinegar may produce the results that they claim, but their reasoning behind it is not at all accurate.
Commercial ACV has a pH of around 2.4 - under any definition, that is an acid. For comparison, water has a neutral pH of 7.0 - an acid is defined by having a pH of less than 7.0. The lower the pH, the more acidic a substance becomes. Conversely, a substance has to have a pH of above 7.0 to even enter the alkaline range.
I don't care what ACV may or may not do when it enters the body and is digested. Pre-digestion, it is acidic. When you put it in your mouth, when you swallow it and it goes into your stomach, it is an acid. Does it cause any damage? That's debatable, since cola and lemon juice have close to the same pH (
cite).
Issues of chemical composition aside, there is some evidence, backed up by scientific studies, that ACV/acetic acid (see
Carb and Weight Control study information in
Functional Ingredients) may positively affect blood glucose, insulin and satiety responses. Bottom line: it may work. Anectdotally, I can tell you it
does work to some extent (I've been taking it for a week now). But I'd still rather take science over folk remedy any day.