How Often You Should Wash Your Hair and Why

For the average person, you are supposed to wash your hair every other day or every 2 to 3 days. It is best to avoid washing your hair every day because this can over-stimulate your oil glands giving your locks an unhealthy and dirty look. Over washing your hair causes your scalp’s pH to rise making it irritated, dry, flaky and causes a greasy scalp. Not to mention your hair will become static-y and fly away with excessive oiliness.

However, waiting too long to wash your hair allows for a buildup of natural oils, bacteria, and dead skin cells which also causes your hair to get greasy. And when you don’t wash your hair frequently enough, you’ll wind up with scalp issues like dandruff, scalp acne, and excessive greasiness that gets itchy.

Healthy hair needs a clean and balanced scalp, because blocked or clogged follicles affect hair growth. This is why it’s important to wash your hair at the correct intervals.

The frequency of when you should wash your hair depends on the type of hair you have.

While there’s nothing quite like the steamy, warm rush of water as you lather up your scalp, the amount of time to wait between washing your hair changes based on your age, the condition of your scalp, the length and type of your hair, as well as your daily activity level.

Let’s get to the “root” of it and see how each of these changes can affect how often you should wash your hair.

Age

Depending on how old you are, the oil glands in your scalp are more (or less) active. When your glands produce less oil, you don’t have to wash your hair as often. And when you’re younger, your oil glands produce the most sebum causing you to have to wash your hair more often.

Hair oil is a result of active sebaceous glands. These glands secrete an oily substance called sebum that moistens your hair and keeps it from drying out. When you are born, your sebaceous glands gradually stop working, and become nearly inactive between the ages of two and six.

The production of sebum will steadily increase, reaching its highest levels during puberty as boys and girls both experience a sudden spike in male hormones (androgens). Around the age of 20, sebum production slows and continues to decrease the older we get.

Once a woman hits menopause, they have a marked decrease in androgens which then leads to less oil production. The same holds true for men as their testosterone levels also lower as they get older too.

Scalp Condition

The condition of your scalp has an impact too. Dry scalps tend not to produce as much sebum (oil), so washing your hair less often can help your scalp to remain healthy and keep your hair soft and shiny. Oily scalps can develop acne on the scalp itself or along the hairline, and you’ll need to wash your hair more frequently to keep your hair looking clean.

Hair Length

Your hair’s length makes a difference, because sebum needs to make it from your scalp to the end of your hair strands to keep them moisturized. Because it takes longer for the oil to make its way all the way down to your hair’s ends, longer hair often gets dry.

Hair length for this purpose is as follows:

• Short hair stops above the shoulders and is up to 12” for straight hair and 14-16” for waves and spirals.
• Medium length hair keeps going past your shoulder to your armpit (about 12-18” for straight hair and up to 24 inches for curly hair).
• Long hair is anything beyond medium’s length.

Hair Type

Hair type and texture affects how sebum works its way from your roots through the rest of your hair too:

• Coarse and curly hair slows down sebum's spread, so you’ll only need to wash your hair once a week.
• Fine, straight hair is easily coated by sebum, requiring you to wash your hair twice a week or more to keep it from looking greasy.
• Thick and wavy hair allows you to go longer between washes because the sebum has a hard time getting down to your hair strand ends.

Activity Level and Location

If you workout a lot or sweat a lot while working out, you’ll want to wash your hair more often, no matter the length, type, or texture you have. This also holds true for people who live in highly polluted areas, use styling products too much, or have a high allergy count in their area.

Sweat can make your hair look and feel dirty, while causing your hair to smell less than fresh.

Dirt, dust, and pollen can also get trapped on your hair and make your hair look dull (and exacerbate your allergies). If you’re in an area with heavy pollution or you lead an active lifestyle, it is likely good to wash your hair more often.

Determining how often to wash your hair is easy now that you know what washing your hair does. If you have long and wavy hair, you can wash less often than someone who is active in sports with short hair. Subscribe to our newsletter for more hair health, styling and nutrition tips.