Scalp care in Malaysia's hot, humid weather

In Malaysia, it is hot and humid all year. Many people commute in the heat, ride motorcycles under helmets, wear a tudung or cap all day, and work out in warm conditions. All of this means more sweat on the scalp. Here is what the evidence says about looking after your scalp in that climate.

Does humidity affect the scalp?

Sweat itself is normal; it is how the body cools down ¹. But heat and sweat can play a part in several scalp problems:

• Heat rash. Heat rash is usually caused by sweating a lot. Sweat glands get blocked and the trapped sweat leads to a rash of small raised spots a few days later ². It can appear anywhere on the body, including the neck and hairline, and it is not contagious ².
• Fungal infection. DermNet lists warm, humid environments as a risk factor for scalp ringworm ³. See scalp ringworm.
• Dandruff. The AAD notes that dandruff can be linked to oily skin and hair care habits ⁴.

Humidity is not bad for everyone, though. The AAD notes that seborrhoeic dermatitis often flares in winter and early spring, and may even disappear during warm, humid weather ⁵. Scalp responses vary.

How often should you wash your hair in hot weather?

This is the question we hear most. Many people worry that frequent washing strips the scalp. The evidence suggests otherwise for most people.

A 2021 study in Asian adults without scalp disease found that overall satisfaction with hair and scalp condition was highest when people washed 5 to 6 times a week. In a controlled part of the study, daily washing beat once-a-week washing on all measures, with no objective harm to the hair. The authors concluded that concerns about "overcleaning" were unfounded ⁶. Note that this study was funded by a shampoo manufacturer ⁶.

The AAD gives similar advice: if you have straight hair or an oily scalp, you may need to shampoo daily. If your hair is coarse, curly or coily, wash when needed ^{7 4}.

In practice, if you sweat heavily, washing your scalp daily or after exercise is reasonable. See how often to wash your hair.

A humid-weather scalp routine

1. Wash the scalp, condition the ends

Concentrate shampoo on the scalp, not the lengths, and use conditioner on the ends ⁷. This cleans away sweat and oil without drying out the hair.

2. Use a dandruff shampoo if you flake

If flakes or itch are a problem, use a dandruff shampoo. The AAD suggests that people with an oily scalp may shampoo daily and use their dandruff shampoo about twice a week, leaving it on for up to 5 to 10 minutes if the label says so ⁴. See dandruff treatment.

3. Dry before you cover up

Many people in Malaysia tie up damp hair or put on a tudung, cap or helmet straight after showering. Letting the scalp dry first is a simple habit that keeps the scalp from staying damp all day. Use a towel gently, or a dryer on a low heat setting ⁷.

4. Keep cool to prevent heat rash

The NHS advice for heat rash is to keep the skin cool so you do not sweat and irritate the rash ²:

• Wear loose cotton clothing
• Take cool showers
• Drink plenty of fluid
• Pat or tap itchy spots instead of scratching
• Avoid perfumed shower gels and creams

5. Be gentle with headwear

A tudung, cap or helmet worn all day traps heat. Choose breathable fabrics, avoid pulling hair tightly underneath, and rinse or change inner caps regularly. Tight styles worn for long periods can cause traction hair loss ⁸. See hijab and hair loss.

A small 2023 study of women who wear the hijab found that seborrhoeic dermatitis and low vitamin D were associated with telogen effluvium, a type of shedding, in that group ⁹. This does not show that the hijab causes hair loss, but it is a reminder to treat scalp flaking rather than ignore it.

6. Do not share combs, towels or caps

Scalp fungal infections spread through shared combs, towels and bedding ¹⁰. This matters more in warm, humid places.

Does sweat cause hair loss?

There is no good evidence that normal sweating causes hair loss. Problems arise mainly when a sweaty, oily or flaky scalp is left uncleaned or develops an infection. See sweat and hair loss and oily scalp and hair loss.

When to see a doctor

• A rash that does not improve after a few days ²
• Sweating that is excessive, happens at night, or affects daily life ¹
• Scaly patches with hair loss, especially in a child ¹⁰
• Flaking and itch that do not improve with a dandruff shampoo ⁴

The bottom line

Hot, humid weather does not have to mean a problem scalp. Washing often, even daily, is fine for most people, and evidence from Asian populations supports it. Use a dandruff shampoo if you flake, dry your hair before covering it, keep cool, and do not share combs and towels.

Frequently asked questions

Is it bad to wash my hair every day?

For most people, no. A study in Asian adults found daily washing was better than weekly with no objective harm ⁶. The AAD also says people with oily scalps may need daily shampooing ⁷.

Can I get heat rash on my scalp?

Heat rash is caused by blocked sweat glands and can appear anywhere on the body ².

Does humidity make dandruff worse?

It varies. Dandruff is linked to oily skin ⁴, but seborrhoeic dermatitis can improve in warm, humid weather ⁵.

Should I dry my hair before wearing a tudung?

Drying your hair gently first stops the scalp staying damp under the fabric. Use a towel or a low-heat dryer ⁷.

Educational content. Not medical advice.