Oily skin is a common skin concern I see in my dermatology practice. It can feel frustrating, unpredictable, and sometimes impossible to manage. Many people assume oily skin is simply genetic or the result of using the wrong products, but the truth is more nuanced. Oil production is influenced by biology, hormones, environment, skincare habits, and even well intentioned mistakes.
Understanding why your skin is oily is the first step toward caring for it properly. Oily skin is not a flaw. Sebum plays an important role in protecting the skin barrier, maintaining hydration, and supporting a healthy microbiome. Problems arise when oil production becomes excessive or when it is paired with congestion, breakouts, or irritation.
Below are the most common causes of oily skin and what you should know about each.
Genetics
Genetics are one of the strongest determinants of oil production. If your parents had oily skin, larger pores, or acne, there is a good chance you inherited similar tendencies. Sebaceous gland size and activity are largely genetically programmed. People with genetically oily skin tend to produce more sebum across all seasons, not just in warmer months.
While you cannot change your genetics, understanding this helps set realistic expectations. The goal is not to eliminate oil completely but to manage it in a way that supports the skin barrier and prevents congestion.
Hormones
Hormones play a major role in oil production, particularly androgens such as testosterone. These hormones stimulate sebaceous glands to produce more oil. This is why oily skin often worsens during puberty, menstrual cycles, pregnancy, postpartum periods, and perimenopause.
Hormonal fluctuations can also explain why oiliness may suddenly appear later in life, even in people who previously had balanced or dry skin. Stress hormones such as cortisol can also indirectly increase oil production by triggering inflammation and barrier disruption.
Over cleansing and stripping the skin
One of the most common and overlooked causes of oily skin is over cleansing. Using harsh cleansers, scrubs, or alcohol based products can strip the skin of its natural oils. When this happens, the skin responds by producing even more oil to compensate.
This creates a cycle where skin feels greasy shortly after washing, leading to more frequent cleansing and further disruption of the barrier. Oily skin still needs gentle care and hydration. A compromised barrier often looks shinier, feels oilier, and is more prone to breakouts.
Skipping moisturizer
Many people with oily skin avoid moisturizer out of fear that it will make their skin worse. In reality, skipping moisturizer can signal the skin to produce more oil. When the skin lacks water, not oil, sebaceous glands often increase sebum output in an attempt to protect the surface.
Hydration and oil are not the same thing. Proper hydration helps normalize oil production and supports overall skin health. Lightweight, non comedogenic moisturizers can actually improve oil balance over time.
Using the wrong products
Heavy occlusive products and pore clogging ingredients can worsen oily skin. Some products sit on the surface of the skin and trap oil, sweat, and debris inside pores, leading to congestion and breakouts.
At the same time, overly aggressive acne products can irritate the skin and drive more oil production. Oily skin does best with thoughtfully formulated products that support the barrier while addressing excess sebum gently.
Climate and environment
Heat and humidity increase oil production by stimulating sebaceous glands and increasing sweat. This is why many people notice oilier skin in the summer or when traveling to warmer climates. Pollution can also contribute by increasing oxidative stress on the skin, which can disrupt barrier function and worsen oiliness.
Indoor environments matter too. Dry indoor air from heating or air conditioning can dehydrate the skin, leading to compensatory oil production even when the surface feels greasy.
Stress and lifestyle factors
Chronic stress raises cortisol levels, which can increase inflammation and oil production. Lack of sleep, poor nutrition, and dehydration can all impact skin balance. Diet does not directly cause oily skin, but high glycemic foods and excess sugar may worsen oiliness and breakouts in some individuals.
Consistent routines, adequate sleep, and overall wellness play a supporting role in skin health, even if they are not the sole cause.
Age related changes
Oil production tends to peak in adolescence and early adulthood, but this pattern is not universal. Some people continue to have oily skin well into adulthood, while others experience shifts due to hormonal changes. As the skin ages, it may become more dehydrated while still producing excess oil, creating the confusing combination of oily yet tight or irritated skin.
This is why mature oily skin often benefits from barrier supportive hydration rather than aggressive oil control.
The role of skincare routines
Oily skin does not require complicated routines. In fact, simpler is often better. Gentle cleansing, consistent hydration, daily sun protection, and targeted treatments when needed are usually sufficient.
Products formulated with barrier supporting ingredients and a dermatologist guided approach help reduce the urge to over correct oiliness. ERLY Daily Soothe, with its calming and balancing ingredients, is an example of a product designed to support the skin barrier while helping oily skin feel more comfortable and balanced without stripping.
Final thoughts on oily skin
Oily skin is influenced by many factors, most of which are not your fault. Genetics, hormones, environment, and skincare habits all interact to determine how much oil your skin produces. The goal should never be to eliminate oil entirely but to create balance.
When oily skin is supported rather than punished, it often becomes more predictable, clearer, and healthier over time. Understanding the underlying causes allows you to choose routines and products that work with your skin rather than against it.
If you focus on gentle care, hydration, and consistency, oily skin can become one of your greatest strengths, offering natural protection and resilience for years to come. ERLY can help.
