The astral plane is such a plane of existence with which most people are not familiar, a whopping majority being completely ignorant of its existence. Even those rare few who claim to have had out-of-body experience either involuntarily or in a controlled environment never fail to mention the fact that much of this parallel plane is still mostly unexplored and major areas are still undisclosed to them. As is true for all things less known, there always lurks an element of danger - not due to facing the unknown itself but due to not being prepared or not knowing what to expect in an unknown terrain. Here are some possible astral projection dangers that one should consider and make preparations accordingly before embarking upon an astral trek:-
What if something bad happens to your physical body while you're out exploring the astral plane in your spiritual body? Someone might hurt your body, it can be destroyed in an accident (what if there's a short-circuit and the room catches fire?).... the risks are endless. Under such circumstances, neither your material body can take steps to defend itself nor can you consciously guide it to escape the mishap. Worse still, you may not be able to re-enter your body if the damage is too severe, making you as good as dead!
Heard about the silver cord concept? Well, among spiritual people who strongly believe in the paranormal, the silver cord is a spiritual or psychic binder that keeps the astral body attached to the material body at the navel. While this cord has endless capacity to stretch, enabling you to travel really far from your body, straying too far may result in you getting lost in the astral plane. You may argue that by following the cord back you can always find your way, what is the assurance that, that is the way things work in the astral plane as well? Even if it did, then wouldn't it also be possible for the silver cord to get all entangled if stretched too long, especially if your travel route is more like a maze than a highway?
Next comes the aspect of energies. Whether you believe in the paranormal or not, you would be an ignorant fool if you don't believe in the dual nature of the Cosmos. All things, visible, semi-visible or invisible, have positive as well as negative sides. In a lifetime, you get to experience both joy and gloom, meet both good and nasty people, do both good as well as not-so-good acts - it's all about striking a balance. It's all yin and yang, the bad balances the good and vice versa. The point is, when you venture out there, the possibilities are strong that you'll come across various other energies and ethereal vibrations that may or may not be entities. Now, these energies would be of both kind, positive and negative. What if some negative energy takes over you and prevents you from returning to your material plane? Worse still, what if it follows you down to the material plane? I leave the consequences to your imagination!
Last but not the least, your physical body will also be affected by your astral sojourns. Making your psychic body travel out of your material body requires tremendous focus, concentration and mental exertion. If not done under the supervision of an adept spiritual guide, you can very well end up with a ruptured blood vessel in your head to say the least, owing to overexertion of your brain. Also, whatever you experience in the astral plane is likely to be carried back to your material body and get stamped on your physical intelligence in the form of mnemonic information. If the experience is negative, traumatic or frightful, chances are that you'll carry the mental scars of these nightmares for the rest of your life! Also, since mental stress directly leads to a disruption of the metabolic rhythm and the hormonal balance and weakens the immune system, this is very likely to have a heavy toll on your physical health.
Read more at Buzzle:
http://www.buzzle.com/articles/is-astra ... erous.html 
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