Does the water filtered from the water purifier need to be boiled again?

Many people buy water purifiers in order to drink clean and healthy water. So, can the water filtered by the water purifier be directly imported, or does it need to be boiled again before drinking?
The first thing to point out is that if it is a high-quality water purifier, through its five- or six-stage filter element, it can completely filter out floating matter, heavy metals, bacteria, viruses, residual chlorine, sediment, rust and Micro-organisms.

Moreover, some water purifiers on the market can filter the water through various principles such as ultraviolet rays and activated carbon, and there is no problem. However, from a medical point of view, it is recommended to filter and boil before drinking, mainly because after the water is boiled, all the microorganisms in the water will be killed, and drinking is relatively safe. In addition, water companies often add chlorine for disinfection, which may produce trihalomethanes as by-products. After boiling, lift the lid and continue to boil for 3 minutes to volatilize the trihalomethanes.
There are three types of common commercially available water purifiers, namely "filter kettle", "under-cabinet water purifier" and "RO reverse osmosis water purifier". Generally, the filter can only filter impurities and heavy metals. If the stomach is more sensitive, it is recommended to filter the water and boil it before drinking. The under-cabinet water purifier not only filters impurities and heavy metals, but also filters out chlorine gas and Escherichia coli. The filtered water can be directly consumed without boiling.
There is also an ultrafiltration water purifier, which depends on whether the consumer lives in the south or the north. Because there is no way to deal with the problem of hard water scale, it is recommended to boil it and drink it. If the RO reverse osmosis pure water machine is installed, it can be directly consumed. If you want to drink hot water or think that it is healthy to boil it, it is recommended to install a pipeline water dispenser that can be heated.