Comfort and Humidity
It is a surprise to many people that humidity has a great deal to do with their comfort. There are a number of factors that cause this.
Dry air seems to feel cool to the skin. Skin tissue is made up mostly of water. If you subject your skin to air with very little moisture in it, it will attempt to pull air from any readily available source. This includes your skin. As the moisture in your skin evaporates into the air it causes the same cooling sensation that having sweat evaporate does. The heat from your body is used to evaporate the moisture in your skin and increase the humidity in the air. It is often for this reason that you feel a chill when you step out of a steamy shower, not a significant change in air temperature as many people believe.
The drying effect which causes you to feel cooler can also be responsible for damaging your skin. As your skin dries out it loses it's elasticity, causing you to look older than you really are. It also tends to become flakey and itchy when it does not have enough moisture in it. When this dryness affects more sensitive areas such as the lips, face, or even nasal passages it can cause the skin to crack and bleed. Most "spontaneous" nose bleeds are caused by the air simply being too dry. If you are subject to random nose bleeds you may notice that they are usually much more frequent in the winter months when you are inside your home more often and the furnace and cooler temperatures combine to cause much lower humidity than you would normally see in the summer months.
Statistics state that it would take in excess of 256 showers per day to provide adequate humidity for a 2,000-square-foot home during cold winter weather (256 x 1/2 lb./shower = 16 gallons daily). In the absence of a whole house humidifier - air becomes extremely dry in well sealed and insulated homes, and steals moisture from whatever sources are available. Those sources include your nose, throat and skin.