In foggy days, it is not advisable to open the window for ventilation during the day and night. It is best to wait until the sun enters before opening the window for ventilation. If you can wear a mask when you go out, it will be very useful to prevent dust particles from entering the body. Cotton masks are the best, because some people are allergic to non-woven fabrics, while cotton masks are generally not allergic and easy to wash. Wash your face and exposed skin as soon as you come back from outside. In addition, this season is foggy and sunny, because the ultraviolet rays are not enough, the vitamin D in the human body is naturally insufficient, and some people will show signs such as laziness and mood decline, and some vitamin D can be supplemented if necessary. The diet in foggy days should choose greasy and digestible foods rich in vitamins, drink more water and eat more novel fruits and vegetables, which can not only make up for various vitamins and inorganic salts, but also play a role in moistening the lungs, resolving phlegm, relieving cough, strengthening the spleen and tonifying the kidney. Eat less irritating food, and eat more foods such as pears, loquats, oranges, oranges, etc.