It tends to spoil or already be spoiled. Even the pink phenolic young coconut travels a long way to its final consumption. It's overall just not really meant to be consumed so far from the source. Sourness means bacteria, and sinuses are infamous for falling prey to weaker or sparse bacteria in the orifices.
I wonder if this is why it’s recommended to put the lime in the coconut, and then you drink 'em both together,
some people say to they put the lime in the coconut, then then they feel better.
Slightly related, I lived in the 3rd world with coconuts for a while growing up. Coconut water from a roadside stand practically put me in the hospital. I wish they had put the lime in the coconut.
Also line with mangoes is wonderful.
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Anyways I self diagnosed with a fit bit a number of years ago. Doctors skeptical but yes I had sleep apnea. And it’s been a journey since then to self manage the machines and trouble shoot treatment. I was not blessed with great dme suppliers or providers.
I don't know the mechanism behind this. Coconut is accentuating the sinus infection in my case? My situation (deviated septum) makes me allergic to coconut water?
I also (used to) have a deviated septum. This almost seems like a general issue with swallowing, where stuff just backs into your sinuses due to pressure weirdness, and certain types of stuff really promote bacterial/fungus colonies.