Imagine that your hands are exposed to the air for a long time, not only in contact with the dust in the air, but also with countless people. You can't guarantee that everything you touch is clean. Even if you are a serious neat freak, even if you wash your hands countless times every day, it is undeniable that your hands are exposed to the air for several times longer than your feet.
We live in a dirty environment every day, whether it is car exhaust, dust or sweat stains, our bodies are full of bacteria. The weather is hot recently, and sweating in summer is obviously more than in winter or spring and autumn. Of course, sweating is a way for the body to detoxify and promote metabolism. However, if the sweat is not cleaned up in time, you will definitely feel uncomfortable all over. This is what we call dirty.
Maybe you will feel that your feet are not only sweating, but also stuffy in your shoes and socks for a long time, which makes people feel particularly dirty and even don't want to touch them. However, please think about it from another angle. It is precisely because the feet are wrapped in shoes that they are isolated from the influence of air pollution and the bacteria brought by contact with other creatures, so they are not as dirty and smelly as you think. What you have on your feet is the waste produced by the normal functional reaction of your body, which is a part of your body. If you don't even like yourself, you might as well not live.
We inevitably have to deal with different people every day, so physical contact is inevitable, especially those closest to you, so the exposed part is easy to breed bacteria, which are not only produced by yourself, but also brought to you by others. In my opinion, this is really dirty.
Maybe you will say that your feet have more contact with the ground than your hands, and the ground is dirtier. What I want to say is that your feet should be in close contact with the ground for a little less time than your hands are in close contact with the air. Of course, it is undeniable that the feet exercise more than the hands, because walking every day, exercising every day, and being hot every day, so the feet sweat more than the hands, but as I said before, I don't think the sweat from the body is dirty.
I remember discussing this topic with my roommate before. They also think that hands are dirtier than feet, but they all have one question. Why don't people want to touch their feet too much? Maybe we'll know when we evolve to walk without feet. Of course, this is just a joke between friends. In fact, the foot is the second heart of human beings, and many key acupoints in traditional Chinese medicine are on the soles of the feet, which is also the reason why the feet are weaker than the hands.
To sum up, we should not think that our feet are lower than other parts of your body, but should protect our feet better, because our feet are fragile and critical. And it will not be exposed to too much air, so it will not breed a lot of bacteria like hands.