Humans haven't been drinking filtered water for long, and not everyone on the planet now has access to filtered water. Humans have not appeared on the earth for a long time, and the earliest can be traced back to the Homo sapiens 2.5 million years ago.
After more than two million years of evolution, the last common ancestor of modern humans, Homo sapiens, emerged. By 60,000 years ago, Homo sapiens left Africa and spread to the world. It was not until thousands of years ago that humans established a civilization with writing.
For most of human evolutionary history, our ancestors lived in the wild, and like other animals, they drank raw water directly in nature, and did not drink filtered water at that time. According to records, the Chinese started boiling water and drinking boiled water 2000 years ago. However, the real large-scale promotion of drinking boiled water did not begin until the last century.
For a long time in the past, people actually drank raw water directly. Some of these waters are fresh water from rivers and lakes, some are mountain spring water, and some are well water. Many people must have drank raw water when they were young. But today, we rarely drink water directly from nature, and drinking water needs to be treated.
The reason why we now have higher requirements for drinking water is because the industrialization of human beings has led to water pollution, and many raw water in nature is not suitable for direct drinking. In addition, some viruses, bacteria and parasites are transmitted through water, so it is very necessary to sterilize drinking water. If the water can be boiled, the water can be further purified, so we have the habit of drinking boiled water.
Although the ancients did not have the concept of viruses and bacteria, early people have begun to realize that raw water can easily cause people to get sick. In this regard, the ancient Chinese people's response method is mainly to boil the water before drinking. On the other hand, the ancients of the Western world mainly used alcohol to disinfect water.
In contrast, animals are unaware of the potential germs in the water, and they don't use fire or alcohol to treat the water. They can only drink water from nature. It's not that humans can't drink raw water directly, it's just that there is a risk of infection, so we try to purify the drinking water as much as possible.
Humans' long-term drinking of purified water helps reduce the risk of contracting some diseases, which is one reason why human lifespans have increased dramatically in recent decades. The average human body temperature has dropped by 0.4 ℃ compared to the 19th century. Because of the clean drinking water and other reasons, there are fewer cases of infection, and the human body does not need to accelerate the metabolic rate more and increase the body temperature to suppress germs. And those raised by humans, which drink clean water, also live longer than their wild counterparts.
At present, there are still many people in the world who do not have access to clean water. Because raw water is prone to bacteria, those who drink dirty water for a long time are much more likely to suffer from waterborne diseases, which have become one of the leading causes of human death in less developed regions such as Africa.
