Dry skin tends to worsen during the winter season. As
mentioned earlier, there are differences in ceramide
synthesis during winter, with a relative deciency in the
long-chain, more protective ceramides. The low
humidity of a dry environment, either in the winter or
at other times, encourages itch by increasing mast cellnumber and histamine content in the skin, both of
which contribute to itching. Lower humidity also
changes the fatty-acid content of the skin, causing dry
skin. Too much exposure of the skin to water also
disrupts the ability of the cells to act as an effective
barrier. With aging and stress, the skin is less able to
accommodate environmental factors that may
be present.
Interestingly, some buildings have been associated with
the development of dry skin, especially dry facial skin.
People with allergies were more sensitive to skin
changes in “sick buildings.” The more time the person
spent inside the building, the more likely he or she was
to develop dry skin and itching related to it.
Less-frequent cleaning of the building led to more
severe symptoms. High ventilation ows, secondhand
smoke, and lack of in-room temperature controls also
were associated with a higher incidence of dry skin.
Older persons may use diuretic medications, which also
can contribute to general dehydration and dry skin.
They also tend to overuse heaters or air conditioners.
They may apply emollients and skin conditioning
products less often