[AStonesThrow]

That, I am afraid, sounds like utter BS. Consider the mechanical action at play here. (If you will delve into gross sticky nose stuff.)

First, nasal mucus is thicker, more viscous than saline spray. It's produced in normal quantities by healthy people, but that production increases when infections or allergies happen, naturally.

By diluting mucus, and making it runny and watery, you're going to defeat its purpose, which is to trap various debris as you inhale, and stop it penetrating further into the nose and body.

So now your mucus defenses are down, yet you've got a little puffer in hand, constantly forcing saline upwards into the nose, more powerfully than simple inhalations. That very upwards and inwards motion is going to force stuff into your body that didn't want to go there, including germs!

It's absolutely counterproductive and sounds like quackery.

Now, if you already detected irritation or allergies based on foreign objects or germs, for example by discolored or thickened mucus, or more than usual, and then you proceed to carefully flush your passages with saline, Neti pot style, allowing it to drain away and out of the nose and sinuses, that would be somewhat effect, but you'd need to be careflu that you're not forcing it inwards. I mean, that is exactly what a runny nose is for during a cold. Don't thwart a runny nose, just clean it away regularly and work with those natural defenses! UGH! (For that matter, don't aggressively attack mild fevers, because fevers are part of an immune response, not the lethal brain-cooking threat we all fear.)

I wonder if this military researcher was consciously aware that he was spreading misinformation to ordinary civilians... hmm

[orbisvicis]

Airplanes bleed external air from the engines into the cabin, which leads to an extremely dry environment. Possibly dry enough to harden and crack mucus. Or perhaps in dry environments the body just decides not to waste water on mucus generation. I have no idea.

[AlbertCory]

This sounds science-y.

In fact, I use NeilMed, a commercial saline & bicarb powder together with distilled water, and I know from past exchanges on HN that lots of others here do, too. My own doctor said it was fine and lots of her patients do it. The solution runs out the other nostril, which is gross so you do it in private.

I have very few colds, allergies, or sinus infections since starting it, although it doesn't eliminate them all.

This Fort Detrick guy, though... that might be misinformation. I use the spray once a day, twice if I have a cold. Definitely not constantly.

[AStonesThrow]

> The solution runs out the other nostril

Exactly the key for this treatment, indeed.

Sure, in many applications, such as congestion where you can't breathe, you'd need to break up the mucus and eliminate it, without snarfing it in. Your solution sounds wonderful for doing just that.

I happen to sport a full beard, and I'm rather pleased with zero coronavirus infections in five years, not to mention a low incidence of colds and influenzas. A beard represents a man's unique natural defenses against all enemies, foreign and domestic, of the respiratory and digestive systems. Oiling, cleaning, and combing the beard are integral parts of that defense.

But, simply Use As Directed, because as we've seen with talc, oxygen, and religion, if/when people misuse/overuse them, turns into cancer...

[AlbertCory]

I should have mentioned that sometimes afterwards, some solution drips out of your nose when you incline your head forward. Super-embarrassing.