A correction...

...has been made to this post (2nd post before this one). 

And I have to say, some of the links that I saw when I was trying to find an answer were rather confusing:  Nitrates in preserved meats are carcinogens, but nitrates in beans and in vegetables of the Brassica family are considered very beneficial, and you should eat them every day, because they have a "vasodilatory" effect?

These are the exact same nitrates chemically, as far as I know.  Or at least, I think they are in terms of what gets released from them into the body.  I could be wrong!

But I think the answer might lie in how these foods are eaten.  Traditionally, a high-nitrate plant food is eaten with a very moderate amount of meat, which was probably preserved by salting, drying, smoking, and/or some other traditional method.  In modern times, the meats have been increasingly preserved using nitrates--even the "low-nitrate" products typically use extracts from high-nitrate plants for preservation.

So if you eat a meal of say, regular bacon, beans, and collard greens, then you're getting a "triple dose" of nitrates.  That must be a shock to the body's systems, although perhaps the bacon fat slows down the nitrate uptake.  If you replace the bacon with something like a bean-based "meat substitute", then you still are in the same place...unless it is low fat!--in that case, you get the full nitrate load all at once.  This may explain much of the physical weakness and ill-health among some of the country's most careful eaters, as well as some of the country's most careless.

This merits further investigation, but before you go off and experiment on yourself, consider the tragic example of Seth Roberts, who I would call one of the greats of self-experimentation; I used to read his blog daily.  He died suddenly of something that was more or less a heart attack, while out hiking (in several ways it was very similar to the death of George Floyd, now that I think of it:  clogged arteries plus enlarged heart plus significant exertion), in the middle of a self-experiment that involved eating a diet that was very high in butter.

The way to do this more safely is to make a small change--such as taking a few small bites of a food--then wait for it to take effect, observe the results, and only then decide whether to take another small step in that direction, or to back off.  We are far too ungentle with our bodies in this culture.