Has your mom ever told you not to sleep in North. Of course every Indian mom does tell that. She might have told you the reason that long back when four persons were send to all the four directions to explore them only three of them returned , the person went in North direction has not. The reason is ridiculous right, but the rule is right.

Scientific explanation:

You know why your heart is located ¾ th above from bottom rather than situating at exactly centre of your body. It is because it is difficult for heart to pump the blood up again the gravity than pumping down. You know that magnetic lines of force of Earth is directed towards poles so if you place your head in North direction your brain may get pressurized by the magnetic forces resulting in hemorrhages. As your blood vessels in brain are very finer like hair even one extra drop of excessive blood pumped by heart due to magnetic pressure results in hemorrhages. Hemorrhages are not fatal but they have long term effects on your brain like fading memory, dullness etc. In case your system is too weak then it may even leads to your death.