Water has 18 electrons. They are all paired using chemical bonds - covalent bonds. So water is not magnetic. In fact pure water is diamagnetic. Water molecules do not align them selves in a particular direction like in ferro magnetic materials.
When water is poured over a strong ferro magnet, some physical changes occur in water. Due to ion separation, hydrogen and hydroxide ions may separate after some minutes like 20 minutes or half an hour. But water does not become magnetic.
Due to this separation of ions, they behave differently. The surface tension property reduces. The water starts to wet more. It flow more readily. This property is useful in healthier body. Inside our body water can penetrate more readily all parts.
Due to addition of hydroxide ions, we have an increase in the pH of water. That reduces acidity and helps body better.
Magnetic water is not magnetic... it is the water that is kept in a ferro magnetic field for some time....