In addition to advice to keep you healthy, this column contains a real-life million-dollar business idea.

Staff Writer

I’m writing this the day before Thanksgiving which means that some readers are already on a plane. If you’re reading this while flying, I apologize for not posting this sooner.

I recently read an article entitled 4 Things You Should (and Shouldn’t) Do on an Airplane to Stay Healthy, According to Flight Attendants. One item on that list really stood out: don’t use the lavatory.

(That’s not the “1 Thing” so please bear with me.)

Anyway, keep in mind that this is advice from the people who deal with airplane lavatories all the time and who are acutely aware of what other people are doing (and not doing) in those tiny, impossible-not-to-touch-things plastic rooms.

The problem with “don’t use the lavatory” is that following that advice is difficult or even impossible on long trips. I frequently travel non-stop from Boston to L.A., a 6-hour flight. I would have to completely dehydrate myself to manage even half that time without a bio-break.

In any case, avoiding the lavatory might be pointless because (get ready to feel a bit nauseous) the average seat-back tray-table (!) contains over eight times as much bacteria per square inch as the average lavatory flush button.

The problem is that tray tables are often touched by people who don’t wash their hands after… you know… but are seldom cleaned, unlike the lavatories, which are typically cleaned between each flight. Tray-tables are so filthy that gastroenterologists recommend cleaning them with sanitary wipes the moment you sit down.

Good advice, certainly, but with bacteria becoming resistant to antiseptics, sanitary wipes might not be effective. Even then, eating off the tray table is the equivalent of eating off a toilet. Worse, actually.

So, then, what to do? Simple.

As soon as you lower the tray, stick a kitchen garbage bag over it. You’ll still want to sanitize your hands before touching anything that goes into your mouth but at least you’ll be eating from a surface that’s germ-free.

So that’s what everyone should do when flying but I’ve never seen anyone do it.

Anyway there’s a pretty neat business idea there. I don’t know about you, but I’d buy and use a portable seat-tray cover that can be cleaned between trips. (The only ones readily available today are for nursery-themed to amuse toddlers.)

Note: when I looked for a stock photo to include at the top of this post, there were at least a dozen photos that had the silverware resting right on the tray table.

Ewwwwww…..