Sour/bitter aftertaste?

Hey everyone,

I’ve heard people claim that acid basically neutralizes alkalinity.
Take treating an E. coli infection, for example—you'll often see cranberry juice and uva ursi recommended together.
But if you look at their chemical makeup, they're polar opposites, right?
The standard advice usually comes with a warning not to take them at the exact same time,
under the assumption that they just cancel each other out when combined.

Does that same logic apply to mixing grapefruit juice with fresh orange juice?
I drink grapefruit juice, but I find it much easier on my stomach when I pair it with some orange juice.
Are they actually neutralizing one another's effects?

I know this is technically a nutrition question, and I honestly haven't been able to find a specific thread on this topic here.
Please set me straight if I'm totally off base. Thanks in advance for any insight.

Acidity and alkalinity aren't really even in the same conversation here. We aren't talking about two things that have to be perfectly equal but just carry opposite charges. There’s a whole spectrum of substances that lean more acidic or more alkaline.

If some herbal tonic made of cranberry and uva ursi actually loses its punch when you take them together, it’s definitely due to the complex chemical interactions happening between their various components. If the whole thing relied solely on pH levels, we wouldn't bother buying expensive supplements at all; we’d just drink a diluted solution of hydrochloric acid or sodium hydroxide. Or maybe just squeeze a lemon or grab a handful of wood ash. Honestly, it would probably work better.

The stomach is a pretty acidic environment—so if that were actually how it worked, any substance with alkaline properties would just be neutralized instantly.

^Not really. It would just temporarily lower your stomach acid levels, which counts as an effect. It’s a pretty crappy antacid, but it’s still an antacid. 😁

placidjackal36 said:Not really. It would only temporarily lower the stomach acid levels—which is an effect in itself. A total joke of an antacid, sure, but it’s still an antacid. 😁

This is what I was referring to:

Hannah Palmer36 said:They say acid neutralizes base. Is that it? Simple chemistry—or just common sense?
When dealing with an E. coli infection, you’ll often hear people suggest cranberry juice or uva ursi—is there any actual substance to that? Some swear by them as part of the treatment protocol, but I'm curious if anyone here has seen real results.
They’re polar opposites in composition—plain and simple.
Just a heads-up—don't take these at the exact same time. Use them separately.
Because when they're combined, they lose their effectiveness.

If that were actually the case—especially if we're talking about bolded assumptions—no alkaline substance would work at all once it hits the stomach. My point was essentially the same as yours: there are much more complex variables at play when you start talking about neutralizing an effect.

Sure, if a substance actually works and by the way it’s alkaline, then you're on the right track. That said, its effectiveness might just tank if it gets neutralized. But honestly, it all comes down to how the substance is built. With some stuff, dropping it into an acidic environment can permanently mess with its molecular structure, which basically kills whatever it was supposed to do in the first place.