Why Does My Hair Get Greasy So Fast?

Greasy hair can be a frustrating and embarrassing problem for many people. No matter how often you wash your hair, it seems to become greasy again within a matter of hours. But why does this happen?

In this article, we will explore the science behind hair grease, common causes of greasy hair, the impact of lifestyle, myths and tips for how to manage oily hair.

Why Does Hair Get Greasy?

sebaceous gland diagram for the hair
Before we dive into the causes and solutions of greasy hair, it's important to understand the science behind it. The main culprit behind greasy hair is the sebaceous glands.

Color Wow Chief Chemist, Dr Joe Cincotta, says, “The sebaceous glands found in each hair follicle secrete a natural oil called sebum.  This sebum travels down the hair shaft (from root to tip) to moisturize and add lubrication to each hair shaft. Sebum production is controlled by genetics and hormones.”

These glands are found all over our body, except for the palms of our hands and the soles of our feet. The sebum produced by these glands helps to keep our hair healthy and shiny. It acts as a natural conditioner, preventing our hair from becoming dry and brittle.

normal production of sebum
overproduction of sebum

However, when these glands produce too much sebum, it leads to greasy hair. The overproduction of sebum can be caused by various factors, such as genetics, hormonal changes, and even environmental factors.

The Role of the Sebaceous Glands

sebaceous gland diagram

The sebaceous glands are essential for maintaining the health of our hair and scalp. They are made up of tiny cells that are constantly dividing and producing sebum. The sebum travels up the hair follicles and reaches the surface of the scalp, where it spreads and coats the hair strands. 

Sebum acts as a protective barrier, preventing the hair from drying out and protecting it from external elements such as dirt, dust, and pollutants. It also helps to maintain the pH balance of the scalp, keeping it healthy and free from infections.

However, when the sebaceous glands become overactive, they produce an excessive amount of sebum. This can be due to a variety of factors, including hormonal imbalances, stress, poor diet, and even certain medications. When there is an excess of sebum on the scalp, it can make the hair appear greasy and limp.

Can Hormones Cause Greasy Hair?

greasy hair

Hormones also play a significant role in oil production. During puberty, hormone fluctuations can cause an increase in sebum production, which may result in greasier hair. This is why many teenagers struggle with oily hair during their adolescent years.

Similarly, hormonal changes during pregnancy or menstruation can also lead to a greasy scalp. The hormonal shifts that occur during these times can stimulate the sebaceous glands to produce more sebum, making the hair look oily and unwashed.

It's important to note that hormonal imbalances are not the sole cause of greasy hair. Other factors, such as poor hygiene practices, using certain hair products, and even certain medical conditions, can contribute to excessive oil production on the scalp.

What Does Greasy Hair Look Like?

greasy hair close-up
You can usually tell if your hair is greasy if it has a shiny appearance and looks wet even though it’s dry, especially around the roots. Your color will likely look dull and darker too.

Common Causes of Greasy Hair

Greasy hair can be a frustrating and confidence-diminishing problem. Understanding the various factors that contribute to greasiness is crucial in effectively managing and preventing it. Let's explore some of the common causes in more detail:

1. Using the Wrong Hair Products

woman applying serum to hair

The hair products you use play a significant role in the greasiness of your hair. Heavy or oily products, such as pomades, serums, or leave-in conditioners, can weigh down your hair and make it appear greasier. It's crucial to choose lightweight, oil-free products that are specifically designed for your hair type.

Additionally, when applying hair products, it's important to focus on the ends of your hair rather than the roots.

Applying products directly to the roots can stimulate the sebaceous glands and lead to increased sebum production, resulting in greasier hair. 

2. Dietary Factors

foods in a brown paper bag

Believe it or not, your diet can have a significant impact on the oiliness of your hair. Consuming excessive amounts of fatty and oily foods can increase sebum production, leading to greasier hair.

On the other hand, maintaining a balanced diet rich in fruits, vegetables, and lean proteins can help regulate sebum production and promote healthier hair.

Incorporating foods that are high in omega-3 fatty acids, such as salmon, walnuts, and flaxseeds, can be particularly beneficial for maintaining healthy hair.

These fatty acids help nourish the hair follicles and regulate sebum production, reducing the likelihood of greasiness.

3. Stress

stressed woman with both hands pressed up against her face

Stress can wreak havoc on our bodies, and our hair is no exception. When we are stressed, our body produces more cortisol, a stress hormone that stimulates oil production in the sebaceous glands.

This excess oil can make our hair look greasy and unwashed.

Furthermore, stress can also disrupt the balance of our scalp's microbiome. The microbiome is a collection of microorganisms that live on our skin and play a crucial role in maintaining its health.

When stress throws off this balance, it can lead to an overgrowth of certain bacteria that thrive on oily scalps, exacerbating the greasiness.

4. Exercise

dumbbells and a water bottle sitting on top of a white towel next to a pink sports bag

Regular exercise has countless benefits for our overall health, but it can lead to greasy hair if not properly managed. When we exercise, our body temperature rises, causing the sweat glands to produce sweat to cool us down.

This sweat, combined with the natural oils produced by our scalp, can create a perfect breeding ground for bacteria and fungi.

Moreover, the friction caused by activities like running or cycling can stimulate the sebaceous glands, leading to an increased production of sebum. This excess oil can then make our hair appear greasy and flat.

color wow color security shampoo

To combat exercise-induced greasiness, it's crucial to wash your hair thoroughly after a workout. Use a gentle shampoo, like Color Wow’s Color Security Shampoo, that effectively removes sweat, oil without leaving any more residues behind. 

Another helpful tip is to tie your hair up during exercise to minimize contact with your scalp. This can help reduce the transfer of sweat and oil from your scalp to your hair strands, preventing greasiness.

Does Over-Washing Your Hair Make it More Greasy?

It’s a common belief that over-washing your hair can cause it to become greasy. This is actually a myth. No matter how much you wash your hair, washing away your natural oils will not cause your sebaceous glands to produce more oil to compensate for dryness. 

Our rule of thumb? If your hair is greasy, it means it’s time to wash it. For some individuals, washing every day may be necessary, while others may find that washing every other day or a few times a week is sufficient. Experimenting with different frequencies can help you discover what works best for your hair. Visit our guide to how to properly wash your hair for more tips.

How to Prevent Greasy Hair: Our Top Tips & Product Recommendations

If you're struggling with greasy hair, don't worry! There are several steps you can take to prevent and avoid oily hair.

Dr Joe’s take? “My recommendation is wash more often and avoid products that contain high concentrations of oils (natural or synthetic). Only apply conditioners or leave in conditioners from mid-shaft to the ends. Don’t apply at the roots.

Read on to find out more.

1. Choosing the Right Hair Care Products

Using the right hair care products is crucial in managing greasy hair, especially when it comes to shampoo and conditioner. Unfortunately, most shampoos today don’t clean all that well. Instead, they come loaded with unnecessary ingredients that are engineered to stay behind on your hair and scalp in order to deliver certain benefits (i.e., defrizzing, thickening, hydrating, etc.). Overtime, this buildup results in hair that never truly feels clean and gets greasy quickly.

close-up of shampoo being poured into a glass container

For cleaner, grease-free hair that lasts longer between wash days, we recommend our Color Security Shampoo. Its 100% clean, sulfate-free formula does one thing only: cleans! Meaning every ingredient rinses completely off, for your cleanest, healthiest-looking hair.

color wow color security conditioner range

Follow your shampoo with our Color Security Conditioner, available in both fine to normal and normal to thick options. Its weightless formula hydrates and detangles without weighing hair down or leaving it greasy. Pro Tip: Never apply conditioner on your roots (only your mid-lengths and ends) as this can result in buildup and increased greasiness.

2. Lifestyle Changes

Adopting healthy lifestyle habits can significantly impact the greasiness of your hair. Manage stress through relaxation techniques or activities you enjoy. Additionally, it's important to eat a balanced diet, stay hydrated, and exercise regularly to improve overall hair health.

woman with dark brown healthy hair

In conclusion, greasy hair is a common problem faced by many individuals. Understanding the science of hair grease and identifying common causes can help you effectively manage and prevent greasy hair. By making simple changes to your hair care routine and lifestyle, you can achieve healthier, less greasy hair.

Frequently Asked Questions About Greasy Hair

Does Touching Your Hair Make It Greasier?

Contrary to popular belief, touching or brushing your hair does not make it greasier. However, excessive touching can transfer dirt and oil from your hands to your hair, making it appear greasier. So, it's best to avoid touching your hair too frequently.

Is Greasy Hair a Sign of Poor Hygiene?

No, having greasy hair does not necessarily mean you have poor hygiene. While greasy hair can be a result of not washing it adequately, it can also be due to other factors like genetics or hormonal changes. Maintaining proper hygiene and following a suitable hair care routine can help manage greasiness.

Can Hair Be Too Greasy to Bleach?

Greasy hair can actually help mitigate the surface-level damage that happens to hair while bleaching. It’s recommended that you avoid washing your hair for 2-3 days before your bleach appointment. 

Does Hard Water Make Your Hair Greasy?

Yes, hard water can make your hair greasy. Overtime, the buildup of minerals and metals from hard water can make it difficult to go longer between wash days. That’s why it’s important to incorporate a weekly hard water detox into your routine.

Our go to? Dream Filter Pre-Shampoo Mineral Remover. In just 3 minutes, this super gentle spray removes minerals and metals for hair that feels instantly cleaner, plus looks brighter, shinier and silkier.

Can You Train Your Hair to Be Less Greasy?

This is a myth. You can’t train your hair to be less greasy, according to our Color Wow chemist, Dr. Joe:

“What is likely occurring is that your sebaceous glands are getting clogged or plugged causing less sebum secretion. This is not necessarily a good thing since it can lead to infections, acne, pimples, and eventually hair loss. The sebaceous glands do not have sensors that turn on and off depending on how much sebum is on your scalp.”

Does Short Hair Get Greasier Faster?

No, the length of your hair does not determine how greasy your hair gets. The mass of oil that your scalp produces is the same no matter your length of hair. Short hair may appear greasier faster, though, because there is a higher oil to hair ratio, so you’re likely to notice it sooner than on longer hair.


Content reviewed by: Dr. Joe Cincotta, Chief Chemist at Color Wow [October 2023]

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