Probably grew up in abusive-ish households where the parents didn't respect the child's emotions. I only found out I have severe anxiety when I was like 27 years old. It took me a year of having full blown panic attacks to realize what it was. I thought I was just being "weak", because that's what I was taught my whole life.
Of course, it gets trickier as you get older, accumulate experiences. Now the same event can carry a unique meaning for every unique individual that experiences it, and that meaning is sometimes very difficult to infer by simple observation.
Most of the time what's wrong with them is simple. They are being lazy in their thinking, or they are ignorant of the importance of empathy and acknowledging people's experiences, and helping them through it, even if we don't approve of (or even understand) why they are having that experience. That's not an obvious lesson, and its not "written on the tin" of any baby I've seen!
(Caveat: A very tricky case is when someone seems congenitally devoid of empathy or self-reflection (e.g. NPD, or generic sociopath). In that case you're better off not engaging them emotionally at all, and treat them as a rational actor responding to incentives. A variant, the rational actor who clearly understands the power of emotions, who can learn to simulate them, and has no scruples about doing so--this is the nightmare person because not only are they "manipulative", their existence makes life harder for the rest of us with real emotions, who sometimes get accused of being them. BTW I've read some really interesting stuff about successful psychopaths who are totally open about their qualities, good and bad, and have decided to integrate with society in a classically healthy way! So even here, there is hope.)
That doesn’t surprise me at all. Why would anyone instinctively know the terms a psychologist would use to categorize their feelings?
That’s like saying you’d be surprised at how many people don’t know the key of their favorite song.
We have learned over the last decade or so that there are some rather significant direct connections between gut and brain via direct neural signalling. Chemical signalling can occur within about 60-90 seconds--ask a smoker how quickly nicotine can hit their system.
It is not proven/disproven AT ALL that the brain isn't responding to direct neural/chemical detection of the water by both the mouth and the stomach.
If that is the case, no, this CAN'T be trained.
The problem I see is that there is no institutionalized way to educate about emotions. For abstract knowledge and training rational thinking we have schools and universities. For feelings/emotions, though, we were are all effecively just getting homeschooled: We can learn from our parents etc., but that's pretty much it.
Perhaps there should be something like a school for feelings. This obviously is a hot topic, though, with different cultures having different ideals etc., especially when it comes to things like purpose in live, like we could already experience in another thread :)
I find one of the fundamental ones is pain. It's not an emotion, but it's not that easy to classify what is actually painful and what isn't. Holding a phone in my hand isn't painful, but at some point I managed to do it so much that it did become painful. I don't know how to describe the pain, but I know that I am apprehensive of holding a phone in my hand for extended periods of time.
Another one is stress. People might not know they are stressed, but they are. They just can't recognize what stress is.
What I'm getting at is that a lot of things aren't taught explicitly. We don't even know how to teach some of that, because we don't have a good classification system for the feeling/emotion.
What I mostly meant was similar to your stress example. Many people don't actually know what stress is, how it manifests, and most importantly, what you can do about it. Many also don't know that people can have very different thresholds of tolerable amounts of stress, and that those thresholds can siginificantly differ for the same person doing different kinds of work/studying etc. (e.g. some people have very low tolerances for arguing/discussions in work groups but can effortlessly dig themselves into research for 8 hours, others can do meeting marathons but have problems with physical work affecting their mood and so on).
In these cases many aspects of both the basic knowledge, ways of prevention and methods of coping with stress are well known, they just aren't taught in regular school. There is slow progress, though. In my country there often are e.g. social pedagogues in primary and secondary schools, helping with these kinds of things - though often only when they already manifest themselves as problematic behaviour.
"Consider what happens when you’re thirsty and drink a glass of water. The water takes about 20 minutes to reach your bloodstream, but you feel less thirsty within mere seconds. What relieves your thirst so quickly? Your brain does. It has learned from past experience that water is a deposit to your body budget that will hydrate you, so your brain quenches your thirst long before the water has any direct effect on your blood."
IMO the point she tries to convey is that the budget doesn't track actual, objective resource use, which also means that individual budget constraints are not only constrained by the actual physiology, i.e. with training (mindfulness and so on) one can move the baseline and thus e.g. stress resistance.
Not a new point either, but you'd be surprised how many people don't know their own feelings. My psych professor told countless anecdotes of patients who didn't know that the disquieting feelings they experienced when e.g. being inside an elevator were actually a panic attack.