Like it or not, hair loss is a fact of life -- and a normal part of the hair growth cycle. You can expect to shed some hair every day, which may be noticeable when you brush or shower your hair, although typical shedding doesn't impact the overall look of your mane. While washing hair is sometimes blamed for excessive hair loss, the process of wetting, shampooing and massaging the hair simply aids in the shedding of already-loose hair strands. If excessive shedding or abnormal hair loss occurs, this is related to something other than shampooing or washing the hair.
Normal Hair Loss
According to the American Academy of Dermatology, it’s normal to shed 50 to 100 hairs per day as part of the natural hair renewal process. In the normal scalp, 90 to 95 percent of hair follicles are in the anogen, or active hair growth phase, which can last up to 8 years. Unless damaged, strands in the anogen phase won’t shed or fall out. The 5 to 10 percent of hair follicles in the telogen phase -- where no active growth occurs -- lose hair strands when new growth pushes out the old, telogen hair.
Hair Wash Impact
Washing hair dislodges the loose telogen hair, making the shedding process more noticeable -- especially when it collects in the drain! If you don’t wash your hair every day, you may shed less than the usual 50 to 100 strands per day, as some of your loose hair strands will stay in the follicles or get held in place by styling products. On hair wash days, the water and massaging of the hair will enable the shedding of your loose hair -- sometimes a worrisome amount. But rest assured, most of the time, this hair loss is normal.
What's Not Normal
It's abnormal to shed, on average, significantly more than 100 hairs per day. Sometimes hair treatments which cause breakage are to blame, such as damage from chemicals, too-tight styles or heat styling. Excess hair shedding due to a stressor, such as a severe illness, significant weight loss or pregnancy, occurs in a reversible condition called telogen effluvium. Certain medications, such as chemotherapy, also cause temporary hair loss. In addition, an array of medical conditions can cause temporary or permanent hair loss. The excessive hair loss from any of these causes will be much more noticeable when the hair is washed.
Washing your hair will not cause excessive hair loss. If you are experiencing more hair loss than usual, see your doctor for an evaluation, in order to determine the cause. Sometimes the hair loss is a consequence of, or a sign of a health problem that needs treatment.
Reviewed by Kay Peck, MPH RD