I’ve never heard of such a thing. When folks use the term “essential oils” they’re generally meaning plant extract based preparations that are applied to the skin or dispersed in a diffuser or such for the aroma to permeate the air - versus something that’s ingested. For clarification, is this what we mean, or referring to something to be taken internally? Essential oils as I’ve defined here are used (by others, not me) not as a preventative measure (as indicated above) might be done for hangover, but rather to produce an effect for an existing condition - for example, some make claims that a certain oil will produce a relaxation effect or reduce a headache. What I’m going to say may be controversial and others for sure would probably argue differently, but my take as a person with a scientific bent is that surely some aromas as well as some ritual practices which may include use of essential oils produce a sensation of relaxation or calm or a feeling of being mentally stimulated and beyond that much of the claims folks make boil down to placebo effect - expectation of a positive result which then is subject to confirmation bias.
Agreed that they are not serious medicine and should not be treated as such. I do like them though, I find them pleasant and relaxing in a diffuser, and for ones not irritating to the skin in a bath, and stress relief does have health benefits. They do have some legit uses for symptom relief. Nothing works better to numb a canker sore or sore gums, eukalytus oil in steam really clears up a stuffy nose. My wife made an antibacterial and antifungal oil mix for me that cleared up a rash that prescription medicine didn’t work on.
So they do have some topical effects but I wouldn’t use them for anything serious, and not internally, that’s for sure.
Taco Bell and a handful of late-night breakfast joints were the only thing available in my neck of the woods back in the day. There were only 2 or 3 Taco Bells in the state, so we would need someone sober enough to make the Border run. Good times