Home » Beauty

Why Is My Hair So Oily? Causes and Expert-Backed Solutions for Greasy Hair

Discover what really causes oily hair and learn effective, expert-recommended tips to achieve fresher, longer-lasting hair days.

By Sneha Tete, Integrated MA, Certified Relationship Coach

Created on Sep 30, 2025

Discover what really causes oily hair and learn effective, expert-recommended tips to achieve fresher, longer-lasting hair days.

Mornings with perfect hair can quickly turn into afternoons of limp, greasy locks—and for many, oily hair is a fact of life that seems impossible to manage. But what exactly causes all that excess oil, and more importantly, how can you actually get rid of greasy hair? Drawing on advice from top dermatologists and celebrity stylists, this in-depth guide answers all your burning questions about oily hair, its causes, and the best ways to get fresher hair days, straight from the experts.

Is Oily Hair Really That Common?

Dealing with oily hair is much more common than you might think. Plenty of people struggle with hair that feels dirty only hours after washing. Whether the culprit is genetics or something in your daily routine, rest assured: there are proven ways to address it, and you’re definitely not alone in the battle against greasy roots.

What Actually Causes Oily Hair?

The visible grease you see on your scalp is primarily sebum—an oily substance naturally produced by your scalp’s sebaceous glands. Sebum helps keep the scalp and hair moisturized, but when it’s overproduced or not effectively removed, it can lead to that dreaded greasy look. According to expert dermatologists, oily hair develops due to a range of factors:

Genetics: Some people are naturally predisposed to produce more scalp oil due to inherited traits.
Oily Skin Type: If your skin tends to be oily, chances are your scalp is, too. Oil can travel from skin to hair roots.
Hormonal Changes: Fluctuating hormones (adolescence, menstrual cycle, pregnancy, or stress) can trigger increased oil production.
Overwashing or Over-shampooing: Washing too frequently can strip away healthy oils, prompting the scalp to compensate by making more oil.
Not Rinsing Out Products Thoroughly: Leftover conditioner, shampoo, or styling product can build up and weigh hair down.
Heavy Hair Products: Using rich conditioners or leave-ins at the roots can cause residual buildup.
Poor Diet: Diets high in fats, dairy, or processed foods may, for some, correlate with excess oiliness (though research is ongoing).

If you find yourself constantly reaching for dry shampoo or planning your life around wash days, one or more of these underlying causes could be at work. The good news? With the right routine adjustments, you can significantly reduce unwanted oil and enjoy balanced, bouncy hair again.

Expert-Recommended Remedies: How to Get Rid of Oily Hair

You don’t have to resign yourself to a lifetime of greasy roots. From the right shampoo strategy to small changes in your haircare habits, here are the top solutions recommended by dermatologists and expert hairstylists:

1. Use a Clarifying Shampoo Regularly

Clarifying shampoos are specifically designed to deep-cleanse the hair and scalp, removing excess oil, product buildup, and dirt. Rotate a clarifying shampoo into your routine once a week (or every other week if your hair is color-treated or prone to dryness). Look for formulas labeled as ‘clarifying,’ ‘detox,’ or containing gentle chelating agents. This can help reset your scalp and keep oil at bay for longer periods.

Related: Best Shampoos for Oily Hair

2. Lower the Water Temperature When Washing

Hot water may feel soothing, but scalding temperatures can actually intensify scalp oiliness. Very warm water strips the scalp’s natural oils too aggressively, causing the sebaceous glands to overproduce sebum in response. Stick to lukewarm water for rinsing, which is gentler on the hair and helps maintain a scalp oil balance.

3. Avoid Conditioner at the Roots

Conditioners add moisture, which is wonderful for dry, damaged ends—but for oily roots, applying conditioner close to the scalp may make matters worse. Instead, only apply conditioner from mid-lengths to ends. Choose lightweight, hydrating formulas with ingredients like squalane or hyaluronic acid, which won’t weigh hair down or leave a greasy finish.

4. Rinse Hair Thoroughly

One of the most overlooked steps is the rinse. If you leave traces of shampoo, conditioner, or styling product in your hair, the residue can quickly start to weigh it down and contribute to oiliness. Always take your time to rinse thoroughly, ensuring no product remains on your scalp or roots.

5. Try Scalp-Balancing and Oil-Control Products

There are numerous specialized products that can help manage oily hair, such as:

Oil-Absorbing Dry Shampoos: Refresh hair between washes and help absorb excess grease instantly.
Scalp Exfoliators: Gentle scrubs and exfoliating serums help remove dead skin and excess oil from the scalp surface.
Scalp Tonics: Formulas with tea tree, witch hazel, or rosemary can help regulate scalp oil and soothe irritation.

The Best Ingredients for Oily Hair Care

Certain ingredients are especially effective in helping to control oil and promote scalp clarity. According to expert reviews, these are tried-and-true choices:

Tea Tree Oil: Known for balancing sebum production, soothing irritation, and removing excess buildup.
Peppermint Oil: Refreshes the scalp and helps normalize pH, discouraging overproduction of oil.
Lemongrass Oil: Natural astringent properties help absorb oil and refresh the scalp.
Squalane & Hyaluronic Acid: Offer lightweight hydration that won’t weigh down fine or oily-prone hair.
Salicylic Acid: Exfoliates the scalp, helping to dissolve excess sebum and prevent buildup.

Surprising Habits That Make Hair Greasier

Some of your everyday habits might be making your oily hair problem worse. Watch out for these sneaky mistakes:

Overwashing: Washing hair too often can trigger the scalp to produce even more oil in response to dryness. Try extending the time between washes gradually.
Heavy Styling Products: Oils, gels, and rich creams used at the roots can exacerbate oiliness. Opt for light, non-comedogenic formulas.
Touching Hair Throughout the Day: Transferring oil from your hands to your hair can quickly make roots greasy.
Dirty Brushes and Pillowcases: Brushes and pillowcases can accumulate oil and product residue, redepositing it onto your scalp. Clean them regularly.

How to Build the Ultimate Oily Hair Routine

Consistent habits form the foundation for less oily hair. Here’s a sample routine to get you started:

Wash: Use a gentle, sulfate-free shampoo most days, and a clarifying shampoo once a week.
Condition: Apply conditioner only on mid-lengths to ends—never at the roots.
Rinse: Thoroughly rinse out all products with room-temperature water.
Style: Use lightweight leave-ins and limit roots to minimal product.
Dry Shampoo: Refresh hair between washes with a quality dry shampoo; apply at the roots and let absorb for a few minutes before brushing through.
Deep Clean: Once per week, use a scalp scrub or exfoliating tonic to remove product and oil buildup.

FAQs About Oily Hair

Q: Why does my hair get oily so fast after washing?

A: Fast-greasing hair is often due to genetics and scalp type, but overwashing can worsen the cycle—your scalp compensates for lost oils by producing more. Consider scaling back shampoo frequency, using clarifying products, and avoiding heavy conditioners at the roots.

Q: Can oily hair be a sign of a health problem?

A: Occasionally, excessive oiliness may signal a hormonal imbalance or underlying condition (like seborrheic dermatitis). If greasiness is sudden or accompanied by flaky patches, redness, or loss of hair, see a dermatologist for evaluation.

Q: What’s the best shampoo for oily hair?

A: Choose a clear, not creamy, formula that is sulfate-free if you have scalp sensitivity. Ingredients like tea tree oil, peppermint, and salicylic acid are particularly helpful for oil-prone scalps.

Q: Is it bad to shampoo every day?

A: For some, daily washing is necessary, especially with very oily scalps. However, for many people, overwashing can create a vicious circle of oiliness. Consider washing every other day and using dry shampoo on alternate days.

Q: Does diet affect how oily my hair gets?

A: While evidence is still emerging, some studies suggest that diets high in dairy or processed foods may contribute to excess sebum for certain people. A balanced diet rich in vitamins, minerals, and healthy fats supports overall scalp health.

How Oily Is Too Oily? When to Seek Expert Help

If your scalp seems persistently oily, even after changing products and habits, or if you notice additional symptoms like redness, intense itching, or hair loss, consult a board-certified dermatologist. Conditions like seborrheic dermatitis, psoriasis, and hormonal imbalances may require specialized treatment.

Expert Bios

Dr. Ryan Turner: Board-certified dermatologist and co-founder of TRNR Skin, New York, NY.
Marc Ballance: Celebrity hairstylist and creative director of Ballance Hair.
Dr. Jessie Cheung: Board-certified dermatologist practicing in Willowbrook, IL, Chicago, IL, and New York, NY.

Tips for Long-Lasting Volume and Oil-Free Hair Days

Adjust Your Shower Habits: Use lukewarm water and thoroughly rinse everything out.
Protect Your Scalp: Minimize friction, avoid hats or tight styles that trap oil, and maintain a gentle brush routine.
Manage Stress: Stress can impact hormone levels and exacerbate oil production—regular stress management supports healthier hair.
Switch Up Your Style: Loose updos, braids, and strategic parting can help disguise greasy roots between washes.

Why Is My Hair So Oily? Causes and Expert-Backed Solutions for Greasy Hair

Is Oily Hair Really That Common?

What Actually Causes Oily Hair?