Brown spots on skin are caused by an overproduction of melanin, the pigment responsible for skin color. When skin cells called melanocytes produce too much melanin in one area, it concentrates and appears as a darker patch on the surface. Sun exposure is the most common trigger, though hormonal changes, aging, and post-inflammatory responses also play a significant role. Below, we break down the most common causes, explain the differences between types of dark spots, and share what can actually be done about them.
What are the most common triggers of brown spots?
The most common triggers of brown spots on skin are sun exposure, hormonal fluctuations, aging, and inflammation from acne or skin injuries. Each of these causes the skin to produce excess melanin in localized areas, resulting in patches of discoloration that range from light tan to deep brown. Understanding the trigger behind your specific spots is the first step toward choosing the right solution.
Here is a quick overview of the main culprits:
- UV radiation from the sun or tanning beds stimulates melanin production as a protective response
- Hormonal changes during pregnancy, menopause, or from birth control can trigger melasma
- Aging causes cumulative sun damage to surface as visible spots over time
- Post-inflammatory hyperpigmentation (PIH) occurs after acne breakouts, cuts, or other skin trauma
- Certain medications, including some antibiotics and chemotherapy drugs, can increase skin sensitivity and pigmentation
Most people experience brown spots from more than one cause simultaneously, which is why a personalized approach to treatment tends to work best. Genetics also plays a role – people with naturally deeper skin tones or a family history of hyperpigmentation may be more prone to developing dark spots.
How does sun exposure cause dark spots on skin?
Sun exposure causes dark spots on skin by triggering melanocytes to produce extra melanin as a defense against ultraviolet (UV) radiation. Over time, repeated sun exposure causes melanin to cluster unevenly in the skin’s surface layers, creating the flat, well-defined patches commonly known as sun spots or solar lentigines. This process can happen gradually over years before spots become visible.
When UV rays penetrate the skin, they damage DNA within skin cells. The skin responds by ramping up melanin production to absorb and scatter the incoming radiation, essentially using pigment as a shield. In younger skin, this process tends to be fairly even. But as skin ages and accumulates years of UV exposure, the melanocytes become less regulated, producing melanin in concentrated clusters rather than spreading it evenly.
This is why sun spots tend to appear most often on areas that receive the most sun: the face, hands, shoulders, chest, and forearms. They also tend to darken further with continued sun exposure, which is why consistent sunscreen use is so important once they appear. Without protection, even treated spots can return or deepen.
What’s the difference between age spots, sun spots, and melasma?
Age spots and sun spots are essentially the same thing – flat, brown or tan patches caused by accumulated UV damage, most common after age 40. Melasma is a different condition triggered by hormonal changes rather than sun exposure alone, though UV light makes it worse. The key distinction is cause: sun damage creates age spots, while hormones drive melasma, and the two often require different treatment approaches.
Age spots and sun spots
Age spots, also called sun spots or solar lentigines, are the result of years of UV exposure. They tend to be small, flat, and clearly defined with consistent coloring. They appear most often in people over 40, though younger people who spend significant time in the sun can develop them earlier. Despite the name “age spots,” age itself is less the cause than the cumulative sun exposure that comes with it.
Melasma
Melasma presents differently. It tends to appear as larger, more irregular patches with blurry edges, often in a symmetrical pattern across the cheeks, forehead, upper lip, or chin. It is far more common in women, particularly during pregnancy (when it is sometimes called the “mask of pregnancy”) or while taking hormonal contraceptives. While sun exposure does not cause melasma directly, it significantly worsens it, which is why melasma can be stubbornly difficult to treat without rigorous sun protection alongside any skin treatment.
Why do brown spots appear after acne or skin injuries?
Brown spots that appear after acne or skin injuries are called post-inflammatory hyperpigmentation (PIH). When the skin experiences inflammation from a breakout, cut, burn, or irritation, the healing process can trigger an overproduction of melanin in that area. The result is a flat, discolored mark that lingers long after the original wound or blemish has healed.
PIH is not a scar in the traditional sense – it does not involve changes to the skin’s texture or structure. It is purely a pigmentation response. This distinction matters because it means PIH is generally more treatable than raised or pitted scars, though it still requires targeted care to fade effectively.
People with medium to deep skin tones are more prone to PIH because their skin contains more active melanocytes that respond more intensely to inflammation. Picking or squeezing acne blemishes significantly worsens the likelihood of PIH, as this increases the trauma and inflammation the skin has to recover from. Sun exposure after inflammation also deepens these marks, making sun protection a critical part of any post-acne skin care routine.
What professional treatments remove brown spots effectively?
Professional treatments that effectively remove brown spots include radiofrequency-based therapies, laser skin resurfacing, and targeted energy-based devices that break up excess pigmentation and stimulate skin renewal. These treatments work by addressing hyperpigmentation at its source, either by disrupting melanin clusters, promoting cellular turnover, or rebuilding healthier skin from within. Results vary depending on the type and depth of the discoloration.
At Ocean Aesthetics and Wellness, we offer several non-invasive options designed specifically to address dark spots and uneven skin tone:
- Exion Clear RF targets surface-level pigmentation irregularities, including sun spots, age spots, and post-inflammatory marks. Using radiofrequency energy, it works to clear and brighten the skin without downtime, making it an excellent starting point for most types of brown spots.
- Exion RF Ultrasound Rejuvenation goes deeper, combining radiofrequency and targeted ultrasound to stimulate the skin’s own collagen and elastin production. This approach improves overall skin quality, tone, and luminosity alongside targeting hyperpigmentation.
- Laser Skin Resurfacing using the Waterlase device removes damaged surface layers of skin and stimulates collagen regeneration beneath. It is particularly effective for deeper or more stubborn discoloration, including sun damage and age spots that have built up over many years.
The right treatment depends on the type of brown spots, their depth, and your overall skin goals. For example, mild surface sun spots may respond beautifully to Exion Clear RF alone, while decades of accumulated sun damage may benefit most from a layered approach that combines surface resurfacing with deeper skin renewal.
What all of these options share is that they work with your skin’s natural processes rather than against them. There are no needles, no surgery, and no aggressive downtime involved. If you are unsure where to start, we invite you to schedule a courtesy consultation with Dr. Sugg. She will take the time to understand your specific concerns and recommend a personalized plan that fits your skin and your lifestyle.