Smelly Scalp: Causes, Treatments, and How to Fix It

Ever caught a whiff of something funky and realized it’s coming from your own head? You’re not alone. A smelly scalp is more common than you think — and it can sometimes be a sign of a deeper medical problem.

So, what can cause it? Overgrowth of bacteria or fungi, excess oil production, or even your usual hair care routine are all possible culprits.

The good news? Good scalp care practices (and, in some cases, medications) can treat a smelly scalp.

Below, we break down the possible causes and how to get rid of a smelly scalp once and for all.

Here are some of the most common reasons for a stinky scalp.

1. Excess Oil Production (Sebum Overload)

Your scalp naturally produces oil (sebum) to keep your hair moisturized, but too much oil can create a breeding ground for bacteria and fungi. When these microorganisms break down the oil, they release fatty acids, which can lead to a musty or sour smell.

You’re more likely to develop this issue if you have an oily scalp or a hormonal imbalance.

Infrequent hair washing or using hair oils too frequently (as this leads to oil build-up) can also lead to scalp odors.

2. Scalp Fungus

An unpleasant odor might be a sign of a fungal infection or yeast overgrowth.

Often, scalp odor results from an overgrowth of Malassezia, a fungus that naturally lives on your scalp. In small amounts, it’s harmless. But when it grows out of control, it can lead to seborrheic dermatitis — which can cause dandruff, itchiness, and scalp odor.

What does scalp fungus smell like? Typically, a scalp yeast infection smells like yeast, sour dairy, or cheese. But the scent can differ from person to person.

3. Smelly Scalp Syndrome

Smelly scalp syndrome or smelly hair syndrome is a rare but real condition where the scalp develops a strong odor regardless of hygiene habits. Some people describe it as a scent similar to sweaty gym socks, body odor, or onions.

Although it’s not completely clear what causes smelly hair syndrome, researchers believe it may have to do with overgrowth of certain bacteria or a scalp microbiome imbalance.

Clarifying shampoos, antifungal treatments, and probiotics may help rebalance scalp bacteria.

4. Sweat and Heat Buildup

Your scalp is full of sweat glands. Just like sweaty armpits can smell, so can a sweaty scalp. If you often wear hats, exercise frequently, or live in a humid climate, your scalp may become a moist environment for happy bacteria.

To avoid this issue, wash your hair after workouts, let your scalp air dry fully, and avoid heavy, sweat-trapping hair products.

5. Dirty Hair

Skipping hair wash days too often or using a ton of styling products can trap bacteria, oil, and environmental pollutants on your scalp, leading to a stinky buildup.

You may be particularly at risk of product buildup if you use dry shampoo excessively. While dry shampoo can reduce oiliness and help your hair smell fresh temporarily, you still need to wash your hair to get rid of dirt and excess oil.

6. Hormonal Changes

Certain hormonal changes — like those that come with menopause or hormone therapy — can affect your sweat glands. In some cases, this might lead to excessive sweating, which can cause a smelly scalp.

7. Diet

Certain foods can change the way your sweat smells, and that includes the sweat from your scalp. If you eat a lot of garlic, onions, or sulfur-rich foods, your scalp might have an odor. Alcohol consumption can also affect the smell of your sweat.

If your scalp odor isn’t going away, don’t panic. It’s probably not permanent.

With the right approach, you can eliminate that funky smell and get a fresh-smelling, healthy scalp again.

1. Use Antifungal or Antibacterial Hair Care Products

Malassezia (mentioned up top) thrives in oily, sweaty environments.

To tame oil production and fungal overgrowth, try a medicated shampoo or scalp treatment with antifungal or antibacterial ingredients.

Look for ingredients like:

• Ketoconazole, an antifungal

• Salicylic acid, which exfoliates the scalp

• Tea tree oil, a natural antimicrobial

• Zinc pyrithione, which fights bacteria and fungi

Many anti-dandruff shampoos contain one or more of the above ingredients.

Consider trying our dandruff detox shampoo, which contains pyrithione zinc and salicylic acid. Use it two to three times a week for best results.

2. Wash Your Hair More Frequently (or Less Frequently!)

One of the biggest mistakes people make with scalp odor is washing their hair either too often or not enough.

 Your washing schedule will depend on your hair type, but in general, it’s a good idea to wash your hair every second or third day. You might need to increase or decrease the frequency depending on whether you have dry or oily hair.

But don’t go overboard. Overwashing can strip your hair and scalp of its natural oils, leading to dry hair and scalp. Your sebaceous glands might then overcompensate for the lack of oil by producing more sebum, leading to more oil buildup and odor — a viscous cycle.

Experiment with your hair-washing schedule to see what works best for your scalp. Don’t forget to use a conditioner to keep your hair soft, smooth, and hydrated.

3. Exfoliate Your Scalp

Like your face, your scalp needs regular exfoliation to remove dead skin cells, oil buildup, and product residue. A smelly scalp can sometimes happen due to clogged follicles trapping bacteria.

Using a scalp scrub or a shampoo with salicylic acid can help break down excess oil and skin cells. Scalp massagers can also help loosen buildup while you wash your hair.

Don’t exfoliate your scalp too often, though, as it can have the same effect as overwashing. It can also lead to a dry, itchy scalp.

4. Rinse Hair Thoroughly After Washing

Shampoo and conditioner residue can trap bacteria and sweat, leading to a lingering scalp odor. It can also cause greasy hair and a flaky or oily scalp.

Make sure you rinse your hair thoroughly, especially if you use leave-in treatments or styling products.

5. Avoid Heavy Hair Products

Thick, oil-based products like gels, mousses, and leave-in conditioners can trap sweat, oil, and environmental pollutants. This can cause an oily scalp, a potential breeding ground for odor-causing bacteria.

Try to avoid overdoing it on:

• Heavy waxes and pomades

• Silicone-heavy conditioners

• Dry shampoos

Instead, look for lightweight, non-comedogenic hair products that won’t clog your pores.

6. Keep Your Scalp Dry

Wet or damp hair can lead to bacterial growth, especially if you frequently air dry in a humid environment or go to bed with damp hair.

If you prefer to air dry your hair, here are a few tips to keep in mind:

• Always rinse your hair after swimming to avoid residue buildup

• Gently towel dry your hair as much as possible

• Avoid wearing hats when your hair is still wet

• Try not to go to sleep with wet hair

If you use a blow dryer to dry your hair, try to use it on a low heat setting to avoid heat damage.

7. Adjust Your Diet

What you eat can affect how you smell, including your scalp odor. Some foods contain compounds that show up in sweat, making your scalp smell stronger.

Foods that can make scalp odor worse include:

• Sulfur-rich foods like garlic, onions, and eggs

• Processed, greasy, or fried foods, which can increase oil production

• Alcohol and caffeine, which dehydrate the body and can intensify odors

8. Try Natural Solutions (with Caution)

If you’re looking for natural ways to tackle a smelly scalp, try adding these simple home remedies to your hair care routine.

Popular DIY treatments include:

• An apple cider vinegar (ACV) rinse. Dilute ACV with water (1:3 ratio), pour the solution over your scalp after shampooing, and rinse thoroughly. This may help fight scalp infections.

• Tea tree essential oil. Add a few drops to your shampoo for a natural antibacterial boost.

• Witch hazel. This acts as a natural astringent that can absorb excess oil.

Remember that these solutions, while natural, can have side effects. Always patch test natural remedies before applying them to your scalp to avoid irritation. And avoid applying potent products if you have a condition like scalp psoriasis or eczema.

9. Consult a Dermatologist

If you’ve tried everything and your scalp still smells bad, you might have an underlying medical condition that needs professional treatment.

Chronic scalp odor can sometimes be a sign of infections, skin conditions, or hormonal imbalances.

A dermatologist — or another healthcare professional — can prescribe medicated shampoos or topical treatments to help rebalance your scalp and stop persistent odor.

A smelly scalp can be annoying, but it’s fixable once you identify the root cause.

Whether it’s bacteria, fungi, excess oil, or product buildup, simple changes to your hair washing routine and diet can keep unpleasant odors at bay.

Keep the following in mind:

• Many issues can cause a stinky scalp. Bacteria, fungi, or oil buildup can all contribute to scalp odors.

• There are a few ways to treat it. Consider adding antifungal shampoos or exfoliators to your hair care routine. You might also benefit from adjusting your diet.

• It can be a sign of a deeper medical issue. If scalp odor persists despite good hygiene, see a healthcare practitioner for further evaluation.

Worried about scalp issues? You might benefit from speaking with a healthcare provider. They can help assess the cause of your smelly scalp and go over your treatment options.