Actually leafy vegetable contain more nitrites than bacon. I have found Naked Bacon. It is on sale in Ireland where it is made. It is not available in UK since the UK mandates a legal requirement for processed foods to have it added as a preservative.
the potential for increased risk of certain cancers in adults and methemoglobinemia (ie, blue baby syndrome) in infants. However, more recent evidence suggests that dietary nitrate, as an exogenous source for endogenous nitric oxide production via the human nitrate–nitrite–nitric oxide pathway...
One of my heart meds is akin to nitroglycerine, and provides a nitrogen fix if my heart starts having difficulty. we need nitrogen, and plants fix nitrogen. we feed plants nitrogen fertiliser (ammonia). Amino acids are nitrogen carriers. It is not the nitrates I am having to restrict, it is the potassium. Our water supplies are awash with nitrogen compounds including nitrates and nitrites.
The problem with Naked bacon, apart from the price, is that when you get the pack out of the fridge or freezer you have to use up the whole pack in one sitting since there is no preservatives in at all and it relies on being refrigerated or frozen.