Many of us have heard since childhood that we should not dilute hot tea with unboiled water, because this can cause digestive problems. We decided to find out whether this recommendation has a scientific basis.

Periodically users on the Internet are interested, is it possible to mix boiled and raw water? Discussion of this issue appears not only in Runet, but also on foreign resources Reddit And Quora. The answer was given "Popular Mechanics", "Rambler/female", channel “Nauchpop. Science for everyone".

There are several versions explaining why it is harmful to add raw water to boiled water. According to one of them, unboiled water is “living”, and after boiling it becomes “dead”: beneficial substances are destroyed under the influence of high temperatures. It is believed that “living” and “dead” water have different structures, so mixing them causes intestinal upset.

In fact, water is a simple molecule. An oxygen atom is covalently bonded to two hydrogen atoms. When heated, water may turn into steam, but chemically remains unchanged. There are no vitamins in the water, but there may be impurities and bacteria.

A hundred years ago, many people drank water from wells, and it could contain pathogenic organisms that could only be gotten rid of by boiling. Without knowing the reasons, but simply from life experience, people considered raw water dangerous to health and tried not to add it to drinks or dishes. The historical memory of this is apparently the main reason why people are still afraid to mix boiled and raw water.

Now we use modern plumbing and filters or buy bottled water. To understand whether it can be added, let’s figure out which water is better purified.

Tap water. Almost 90% of Russians live in houses with central water supply. Water coming into the tap undergoes multi-stage cleaning and is considered safe to drink. But the quality of water may differ from region to region, and it also retains a residual concentration of the disinfectant - chlorine.

Filtered water. For many, using home filters is an alternative to purifying water by boiling. Built-in reverse osmosis filters All impurities are removed so well that the water may then require artificial mineralization. But most often people use filter jugs and forget to regularly change the cartridges, which is why they become bacteria begin to multiply. And the benefits of such water are very conditional.

Bottled water. According to a survey by VTsIOM, 16% of Russians regularly drink bottled water. Basically it's the same filtered water, but bottled in plastic containers. If stored incorrectly, such as reminds Rospotrebnadzor, such water can become hazardous to health after some time.

Boiled water. Boiling water is a simple and effective way to purify water and kill harmful bacteria. Recommended bring the water to 100 °C and keep on fire for at least another minute. One study found that flash boiling and water filtration reduced the concentration of drinking water disinfection byproducts. approximately 90%. When even a little raw water is added to boiled water, the liquid becomes unboiled.

If you are confident in the quality of filtered, bottled or tap water, then it can be absolutely safe to mix with boiled water. And if in doubt, use water only after boiling. It disinfects water 100%, so it cannot cause diarrhea or other digestive disorders.

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