How often should you wash your hair?

How often should you wash your hair? It is one of the most common hair care questions, and the answers online range from "every day" to "as rarely as possible". Many people also worry that frequent washing causes hair loss because they see hair in the drain. This guide explains what the evidence says and how to find the right routine for your hair and scalp.

The short answer

Wash your hair based on how quickly it gets dirty or oily. The AAD puts it simply: if you have straight hair and an oily scalp, you may want to shampoo every day. If your hair is dry, textured, curly or thick, shampoo when needed, at least once every 2 to 3 weeks ¹.

That is a wide range, and it is meant to be. Hair type, scalp oiliness, climate, exercise and headwear all make a difference.

What the research says

Few studies have looked closely at wash frequency. One of the most detailed included two studies of Asian adults without scalp conditions ²:

• In a study of people's natural routines, overall satisfaction with hair and scalp condition was highest among those washing 5 to 6 times a week, on both objective and self-rated measures.
• In a controlled study, daily washing was better than washing once a week on all the measures used.
• No objective harm to the hair was seen at daily washing.

The researchers concluded that concerns about "overwashing" were not supported in the groups they studied ². The study was funded by a shampoo company, and it looked at Asian adults with healthy scalps, so the results may not apply to everyone, especially people with very dry or tightly curled hair ².

Does washing cause hair loss?

No, washing does not cause hair loss. Hairs that come out in the shower are mostly hairs that were already at the end of their life cycle. DermNet explains that shed resting hairs have a small bulb at the end, called a club hair ³. Washing and combing simply release hairs that were going to fall anyway. If you wash less often, you will see more hair come out at once, which can look alarming but is not extra hair loss.

If you are shedding much more than usual, the cause is usually something else, such as illness, stress or medicines ³. See sudden severe hair fall.

Finding your routine

Oily scalp or fine, straight hair

Oil shows quickly on fine, straight hair. Daily or near-daily washing is often comfortable ¹. The AAD dandruff advice also suggests people with an oily scalp may do better washing daily ⁴. See oily scalp and hair loss.

Dry, curly, coily or thick hair

Curly and coily hair often feels dry along its length. Washing less often may suit you, as long as your scalp stays comfortable ¹.

Flaky scalp

The AAD notes that flakes can sometimes come from not shampooing often enough ¹. Dandruff is not caused by poor hygiene, but it can be more visible if you wash less ⁵. See dry scalp vs dandruff.

Lots of sweat, heat or headwear

If you sweat during exercise, ride a motorbike or wear a tudung or cap for long hours in Malaysian heat, washing more often may feel better. Make sure hair is dry before you cover it. See sweat and hair loss and humid weather and hair.

How to wash well

How you wash matters as much as how often. The AAD recommends ¹:

• Shampoo the scalp, not the whole length of your hair. This removes oil, dead skin and product buildup without drying the hair too much.
• Use conditioner after every wash. Put it on the ends if your hair is fine or straight, and along the full length if it is dry or curly.
• Be gentle with wet hair. Use a wide-tooth comb instead of a brush.
• Pat, do not rub. Wrap your hair in a towel or T-shirt to absorb water.
• Limit heat. Use a low or medium dryer setting.

The AAD's advice for people with thinning hair is similar: use a gentle shampoo and a moisturising conditioner after every wash ⁶.

When washing may irritate

Washing can dry the skin if water is very hot or cleansers are harsh. DermNet lists excessive bathing and contact with soap and detergents among the causes of dry skin, and suggests lukewarm water and gentle cleansers ⁷. If your scalp feels tight or itchy after washing, try:

• Lukewarm water instead of hot
• A milder shampoo
• Washing a little less often
• Rinsing thoroughly

Signs to see a doctor

Your routine is unlikely to be the problem if you have ⁵:

• Flakes that do not improve after 4 weeks of anti-dandruff shampoo
• A red, swollen or very itchy scalp
• Flaky patches on your face or body

Sudden heavy shedding or patches of hair loss also need a doctor's check. See alopecia areata.

The bottom line

There is no fixed rule. Wash as often as your scalp needs, which may be daily for an oily scalp or every few days or weeks for dry, curly hair. Research in Asian adults suggests frequent washing is not harmful. Focus shampoo on the scalp, condition the ends and be gentle with wet hair. Hair in the shower is normal shedding, not damage caused by washing.

Frequently asked questions

Is it bad to wash my hair every day?

For most people, no. A study in Asian adults found no objective harm from daily washing ². The AAD says people with an oily scalp may want to wash daily ¹.

Does washing make hair fall out?

No. Hairs released during washing are mostly resting hairs that were going to shed anyway ³.

How often should curly hair be washed?

The AAD suggests washing dry, curly or thick hair when needed, at least once every 2 to 3 weeks ¹.

Should I shampoo my whole head of hair?

The AAD recommends focusing shampoo on the scalp and using conditioner afterwards ¹.

Educational content. Not medical advice.