Many people don’t wash their hair every time they bathe — and for good reason. Over-washing can strip natural oils from your hair, making it dull, dry, and coarse.
But not washing your hair enough may lead to conditions like dandruff or itchy scalp.
How often you should wash your hair can be different for everyone, depending on your activity level and the type of hair you have. Knowing more about hair and scalp health can help you figure out the best hair-washing schedule for you.
Despite all of the potential benefits, there are also side effects of not washing your hair, especially for an extended period of time.
It could slow hair growth
The main factors that affect hair growth and the growth cycle are:
- genetics
- nutrition
- stress
- overall health
- hair care
Treating your hair gently can promote hair health. This can include things like using a towel gently, not using hairdryers or turning down their heat, and going to a salon.
If you don’t wash your hair, dirt and hair care products may build up on your scalp, potentially affecting hair growth.
Oils and grime can be trapped, creating odor
When you don’t wash your hair, oils may accumulate on your scalp. This can cause odor on the scalp and hair.
If you use hair care products, these can also build up on your scalp and create odors, even if the products themselves smell good.
Hairs may become ingrown
If there’s buildup of product or oils on the scalp, you might experience ingrown hair. This is when a hair grows back into the scalp. It’s often painful.
To help treat this, you can do the following:
- Apply warm compresses to the area at least three times a day.
- Use gentle scrubbing after the compresses with a moist washcloth.
- Shampoo daily with a soothing antiseptic shampoo.
- Moisturize the scalp.
- Avoid covering your head.
Dandruff
Dirty hair itself doesn’t cause dandruff. However, oily buildup from not washing your hair can cause flakes.
Most cases of dandruff can be treated with over-the-counter dandruff shampoo. If it doesn’t help or you notice the flakes getting worse, see a dermatologist.
Itchy scalp
An itchy scalp can occur for a variety of reasons, including:
Finding out the underlying cause of the itching can help you address it.
There are some benefits to not washing your hair, especially if you have dry hair, damaged hair, or tightly curled hair. Depending on your ethnic background, less frequent washing can also help reduce breakage and hair loss.
People with tight, coiled hair are at a higher risk for hair loss and breakage from a condition called acquired trichorrhexis nodosa (TN). Repeated heat styling and chemical processing can damage the outer protective layer of the hair shaft. This can then change the hair’s protein structure, causing weak points and breakage.
This is especially true of Black people’s hair, since the fibers have an asymmetric shape and curvature, making them more susceptible to breakage due to weakness.
Washing hair less often is suggested to minimize the impact of TN.
Additionally, oils have a harder time coating curly hair. By not washing as often, the sebum can coat the hair more, providing some protection.
When it comes down to it, the benefits you experience may depend on the kind of hair you have. If you have oily hair, you may need to wash it more often. But if you have natural hair or coarse, curly, or dry hair, washing it less often can yield benefits.
There’s no scientific proof that people with oily hair can “reset” oil glands in the scalp.
Are there any benefits to not washing hair for a week?
Not washing your hair for a week can have different benefits, depending on the kind of hair you have.
Washing hair once a week, or even every other week, can help prevent the hair from drying out while also removing any buildup of hair products.
Chemically treated hair and hair of older people may be drier, so not washing it for a week can help prevent it from drying out.
Right now, there’s not any research on how long someone can go without washing their hair. Some people find alternative ways of washing their hair and have been using these methods for years. Some of these methods include:
- dry shampoo
- co-washing, or washing with conditioner only
- washing only with water
Because each person’s hair, lifestyle, and personal preferences are different, there’s no one prescribed length of time that someone can go without washing their hair.
Everyone’s hair is different.
Depending on the makeup of your hair, your activity level, and personal preferences, you may find that washing your hair less often is helpful. For many people with oily hair, washing more frequently may be necessary.
Finding a routine that works for you and your hair is the most important goal.
If you’re having persistent oily hair or scalp issues, see a dermatologist. There may be underlying health issues that need to be addressed that go beyond washing the hair.