We drink water not only for the hydration benefits, but for the mineral benefits it provides. Pure drinking mineral water is essential for a body to get some nutrients not commonly found in the food we eat. For instance, in very low doses, iron in the water is helpful to us and without specifically seeking it out in our food we will not get the iron we need. Drinking demineralized water can lead to cancer and mineral deficiencies.
It is a good idea to find filters that will not remove the minerals in the water. Most filters will have their parameters on the boxes when you purchase them. As a guideline though, reverse osmosis and distillation strip tap water of its minerals leaving it less pure drinking mineral water. Carbon filters however do not remove the trace minerals from tap water.
However, some minerals are radioactive. Knowing if you are in an area that could possibly have radioactive minerals in the water is something you may want to consider. It is likely that radioactive minerals will be more likely to cause cancer than the reverse osmosis or distillation processes of your filters.
A carbon filter will be best to use in cases where you do not want to remove the minerals from the water. A balanced nutritional diet will consist of pure drinking mineral water. These minerals will fit your body with the probable missing minerals that we all need to survive and flourish. There are some times when demineralized water is necessary or at least acceptable. If you are taking the proper multi-vitamins for your age or physical condition then reverse osmosis or distillation might not be a bad option for you. Keep in mind, however, that reverse osmosis does not remove chlorine from water.