My opinion based on my experience.....Yes astral projection and out of body experiences are both types of lucid dreams, and you don't have to worry about getting stuck outside your body. However, it does not follow that there's nothing else going on during the experience besides the relatively superficial lucid dream aspect of it. And it doesn't follow that doing it a lot is good for you, that you won't develop some kind of dissociative disorder. If you have a feeling like its not healthy for you, maybe its not. I don't find people's assurances that its completely harmless to be very convincing when nobody can more than partially explain what the experience is.

Everybody has slightly different definitions for 'astral projection' and 'OBE', but here are mine. Astral projection is when your tactile mental model of where your body is goes out of agreement with where your body actually is. OBE is when you transfer your visual/cognitive sense of where you are to the perspective of a third person witness. It may not have quite the same wow to it as the astral projection experience, because that third person perspective doesn't have as strong of a full body touch component to it. But various experiences are possible that blend different aspects of this.

During your normal waking life, you experience a sort of internally generated cartoon of the external world. That cartoon includes information from the external world, but you're not experiencing the external world directly. So for instance color is roughly assigned to different objects depending on what wavelengths of light they reflect/emit, but light itself doesn't have color, that's a part of the cartoon. The waking experience is very much like a lucid dream, the difference is that when you're awake, your mind works to keep the lucid dream closely aligned to what's going on around you so that you can use it to help you interact with your environment. When people realize 'Oh my god, life is just a dream', they're recognizing that their experience is a dream, and usually failing to recognize that there's an objective reality beyond the dream that the dream represents. I think that the 'objective reality' is a dream too in a sense, but its a more collective dream with a lot of inertia and a way that it works that can't be easily changed by your personal dream.

During the waking life experience, in addition to the 'I am here' mental simulation of yourself, you also have a sense of how other people might perceive you. This is sort of like court awareness when playing basketball, or how socially aware people know the effect their appearance has on other people. My claim is that this is the kind of mental model you're using during a typical out of body experience, but you're transferring part of your first person perspective to it. It doesn't have as strong as a tactile component because the tactile component is how you control you body, and the model that you use for imagining your body from another vantage-point never has that.

A person could quibble and say that there's really just one reality, and the personal 'cartoon' of reality is a part of it, rather than drawing a division and saying they are two different things. I think that's sort of true, one's personal experience is a part of reality, however, if you pay attention to how vision works, for example, you find that there are a lot of ways that it approximates what's going around you and doesn't tell you a completely true story. So I think there's a natural division there, even if its not absolute.

Almost everything I've said so far makes it sound like I agree with the people who say that astral projection is 'all in your head', so to speak. The reason I don't agree with that, is I have precognitive and telepathetic experiences that many people would consider to be impossible. So when other people report similar experiences during astral projection or out of body experiences, I'm inclined to think that they're not all entirely deluded. And it seems to me that the sort of thing that I do with my sense of identity that facilitates my experiences isn't entirely different from what a person does when they astral project or otherwise go out of body. Yes its a lucid dream, but no that isn't the whole story.

I don't agree with people who say that the astral experience is entirely 'real' either. In my experience, messing around with it, there is definitely a degree of disagreement between what my 'astral' experience is telling me is going on and what is really going on physically. A person can just assert that the astral experience is 'real', but I don't see any reason to say its more real than any other lucid dream, other than that you may have more kinds of sensory imagination involved, and its superimposed on your present picture of where you really are. Even having objectively verifiable paranormal experiences while astral projecting doesn't make it more real than a lucid dream, because people can have paranormal experiences while lucid dreaming also.

I am interested in understanding 'astral' subjects better. But generally when I question people about what they know, it seems that they've had basically the same experiences as me, dressed up by a lot of assumptions that they've read in books. Plus those thoughts are a part of what makes the experiences to start with. Since my experiences don't fit entirely within the 'astral plane' paradigm, it seems to me that it can't be totally correct. I remain open to people describing new angles on this that I haven't thought of though, or helping me understand where I err in some of my thinking about it. So my current thought is that the 'astral body' is a mental projection, and its a mental projection that has some kind of power that we don't understand, and that's all I know. I guess this doesn't necessarily contradict the thoughts of people who think in terms of astral bodies and whatnot.

A possibly peculiar characteristic of my dream life is that I don't have recurring dreams. Dreaming is a very big part of my life, but I only dream of something once and that's it. If I dream of the same thing twice, that's unusual and usually there's a point to it. Astral projection has been like that for me also. I've had several different kinds of related experiences, but have not repeated any of them. So when I say how something feels to me I'm just reliving a vivid experience in my mind.

The first time I astral projected it surprised me and I was scared I wouldn't get back in. Also I could see and hear all kinds of creepy things, such as one might sometimes feel in old houses without being able to see or hear them, and I found that unpleasant. The next experience I had I inverted my audial and spatial sense of inside and outside, so that outside was inside and inside was outside. A weird aspect of this is it happened with one hemisphere of my head at a time, flipping back and forth, and sometimes both sides together. Maybe this doesn't sound like astral projection, but its the same sort of thing, screwing around with a mental map. Next experience I levitated out of my body, and experimented with it, going back and forth until I convinced myself that I was just manipulating a mental model and not really going out of my body. It wasn't until years later that I realized that just because I can describe one aspect of something doesn't mean I understand the whole thing. The last experience I had was more recent, and it was what I'm calling an out of body experience.

If you think astral projection is a problem for you and it happens involuntarily when trying to lucid dream, my suggestion would be not to lucid dream in the conventional sense. I realize this is complete heresy on this site, like telling people not to smoke on a weed website, but right or wrong that's how it looks to me. You can be conscious while you're asleep without trying to create a lucid virtual reality experience. Just think about things, explore different kinds of experiences without trying to control the sensate aspect of your dream experience. Technically that's still a lucid dream, because you're asleep and you know you're asleep, but it seems less likely to me to lead to an unwanted out of body experience. It works for me anyway, though of course I'm not you.

As a side note, of course these types of things tend to be hereditary, just like athletic ability or math skill or schizophrenia or practically anything else.

As another side note, I haven't used drugs or alcohol during any of these experiences, and I think that if a person wants a sober understanding of what this stuff is, its best to do it sober. Also, if you have unwanted dreamlike experiences of any kind its probably best to lay off any substances such as people use to stimulate desired dreamlike experiences.

Along similar lines, if you try to suppress unpleasant thoughts or emotions without facing with them in an honest way, that stuff will tend to force itself out when it gets a chance, such as in weird dream experiences. If you're psychologically healthy, and honest in your interpersonal relationships, I think the less pleasant dream stuff tends to go away. Everybody is a little bit different of course.

I hope that helps somehow.