What Is Sebum?

Sebum is an oily substance produced by your sebaceous glands. You have sebaceous glands all over your body, but they are most concentrated on the face and scalp. Sebum protects and hydrates your skin, but too much sebum production can contribute to acne, oily skin, and an oily scalp. Too little sebum can cause dry, flaky skin.1

Several factors may cause an overproduction or underproduction of sebum. If an overproduction of sebum is causing excess oils on your skin and hair, there are a few things you can do.
What Does Sebum Do?
Sebum is secreted throughout the body and plays an important role in skin homeostasis. It helps keep your skin hydrated, moisturized, and lubricated. It seals in moisture on your skin, which helps prevent dry skin.1

Sebum also protects your skin against environmental hazards and infectious agents, like bacteria and fungi.1 There is evidence showing sebum also has antimicrobial effects, and aids in the synthesis of vitamin D in your body.2
How Is Sebum Produced?
Sebum is produced by the sebaceous glands, which are located below the surface of your skin, near the hair follicles.3 The glands produce sebum through an activity called holocrine secretion, meaning sebum is pushed out along with dead cells.1

You have sebaceous glands all over your body, except for the palms of your hands and soles of your feet.3  Sebaceous glands are most concentrated on the face, back, upper chest, and scalp. These are typically the areas where overproduction of sebum can become problematic, contributing to oily skin and acne.4

The amount of sebum you produce changes throughout your life and in response to environmental factors. For example, sebum production increases during the summer time, as the heat index increases.2 Sebum production also sees a steep rise during puberty.4
Sebum Composition
The cells that secrete sebum in your sebaceous glands are called sebocytes. During sebum production, sebocytes will self-destruct and follow sebum out of the sebaceous gland.1

Sebum is a thick, sticky, oily substance composed mostly of fats (lipids).4 The main components of sebum are:3

Free fatty acids
Wax esters
Benefits of Sebum
Sebum plays an essential role in protecting your body and your skin, and has several health advantages. Some of the benefits of sebum include:5

Moisturizing and lubricating your scalp and hair
Moisturizing your skin and keeping it smooth
Forming a protective barrier on your skin and scalp
Locking in moisture and preventing dry skin
Protecting your skin against foreign agents, like bacteria
Contributing to skin homeostasis and protecting against inflammation
Having antioxidant effects on the skin
Sebum Underproduction
Since sebum is a moisturizing agent for the skin, having low levels of sebum can contribute to dry, itchy, flaky, irritated skin.6

Sebum underproduction can be caused by a number of issues. First, sebum production slows naturally as we age. It starts to decrease for women after menopause and for men around the age of 60 or 70.4

Other contributing factors to sebum underproduction dry skin include:6

Having a medical condition like thyroid disease, diabetes, and kidney disease
Taking medications like diuretics and statins
Having a vitamin deficiency, such as a vitamin D, zinc, iron or vitamin A deficiency
Undergoing cancer treatment
Experiencing anorexia
Being HIV positive
Treatment for sebum underproduction can include addressing an underlying medical condition, vitamin deficiency, or discussing any medication you are taking with your medical provider. In the case of medications, your provider may be able to offer alternative drugs that are less drying.6

Sometimes it’s not possible to correct sebum underproduction. Applying moisturizing skin products can help protect your skin and prevent dryness. A dermatologist can help you determine the best products for your skin. You may also want to refrain from activities that dry out your skin, such as using harsh cleaners or taking hot showers for extended periods of time.6
Sebum Overproduction
High levels of sebum can lead to excess oil on the skin and hair, which may contribute to acne. Many people experience an overproduction of sebum at some point.

During puberty, there is a sharp increase in sebum production. Men may have higher sebum levels as sebum production is related to high testosterone levels. In women, sebum tends to increase during ovulation. Sebum production also varies between one person and another, which is why some people seem more prone to oily skin.4

The most common problem associated with increased sebum production is acne. Up to 80% of people experience acne in their lives and about 20% of the time, it can be severe. Sebum overproduction isn’t the only factor that causes acne, but it is strongly associated with an increased likelihood to develop acne. Elevated production of sebum can cause sebum plugs, which contribute to the development of different types of acne, such as blackheads and whiteheads.1

Overproduction of sebum can also contribute to having an oily scalp or oily hair. When excess sebum is combined with decreased showering, residue from shampoo and conditioner, sweat, and dirt, unwanted symptoms can develop. Symptoms may include bad odor, greasy hair, and an elevated risk of scalp irritation and infections.7
How to Reduce Sebum Production
Excessive sebum production (oily skin) can be managed by changing your skin care routine and using topical and systemic medications that decrease sebum production.

Follow a Skin Care Routine for Oily Skin
Typically, oily skin caused by sebum production can be managed by changing your skin care routine. Try the following steps to control oily skin:8

Wash your face in the morning, evening, and after working out
Only wash your face with mild, non-irritating cleansers
Avoid cleansers that are oil or alcohol based
Use oil-free skincare and makeup products
Use a daily moisturizer formulated for oily skin
Use sun protection daily
Use blotting papers during the day absorb the oil on your skin
Refrain from excessively touching your face during the day
Apply Topical Agents
If you are experiencing acne as a result of oily skin, these topical agents may be helpful to you:9

Benzoyl peroxide (Benzoyl)
Topical antibiotics
Topical retinoids
Topical dapsone 5% gel (Aczone)
Azelaic acid (Azelex)
A dermatologist can help you determine which of these is most appropriate to you and whether you should combine these products together as part of your skincare routine.

Take Medications
Certain medications work directly to decrease sebum production in your body. These medications may not be appropriate for everyone, which is why they need to be prescribed by a medical provider who can determine if they are right for you.

Medications that decrease sebum production include:4

Isotretinoin (Zenatane), an oral retinoid
Spironolactone (Aldactone), which can be used by women only
Oral contraceptives, also for women only
Manage Oily Hair
If sebum overproduction is contributing to oily or greasy hair, you can try these steps:7

Wash your hair as regularly as possible
Consider using a scalp exfoliator to manage the excess oil buildup
Use shampoos and conditions meant for oily hair
Brush your hair regularly to reduce oily buildup
When to See a Healthcare Provider
If you are dealing with excessively dry or oily skin or scalp, you should visit a healthcare provider. Addressing sebum-related skin issues can help improve your quality of life. It’s also important to address sebum imbalance because untreated dry skin or acne can lead to medical issues like skin infections.10

Usually board certified dermatologists are the best providers to help manage overproduction or underproduction of sebum. Skincare issues can be complicated and there isn’t always a one-size-fits-all approach. A medical professional can help you figure out the issue and the best treatment.