There is no proven way to fully prevent seborrheic keratoses. These common, benign skin growths are driven primarily by genetics and aging, two factors you can’t control. That said, understanding what contributes to their development can help you take reasonable steps to reduce how many you get and how quickly they appear.
Why Seborrheic Keratoses Are Hard to Prevent
Seborrheic keratoses form when immature skin cells called keratinocytes multiply in a benign, clonal pattern. The triggers for this process are largely built into your biology. Genetic mutations in growth-signaling pathways (particularly one involving a receptor called FGFR3) drive the expansion of these cells, and a strong hereditary component determines whether you’ll develop many of them. If your parents had dozens of seborrheic keratoses, you’re more likely to as well.
Age is the single biggest predictor. Most people develop their first lesions after age 50, and the number and size tend to increase from there. But they’re not exclusive to older adults. A study examining 170 people between ages 15 and 30 found that nearly 24% already had at least one seborrheic keratosis. Prevalence climbed from about 16% in teenagers to 32% in those aged 25 to 30. In other words, these growths can start appearing surprisingly early, and almost everyone will develop some eventually. People with lighter skin tones tend to get them more frequently.
The Role of Sun Exposure
Cumulative ultraviolet radiation is considered a major risk factor for seborrheic keratoses. UV exposure increases the production of a protein called amyloid precursor protein in the skin, and this protein is found at higher levels in seborrheic keratoses compared to surrounding normal skin. The connection between UV damage and these growths also helps explain why they become more common with age: older skin has simply accumulated more sun damage over a lifetime.
No clinical trial has directly tested whether sunscreen prevents seborrheic keratoses specifically. However, a randomized controlled trial of 588 adults in Australia showed that daily use of a broad-spectrum SPF 17 sunscreen reduced the development of solar keratoses (a different but UV-related skin growth) by 38%, with a clear dose-response relationship. The more sunscreen people applied, the fewer new lesions they developed, and the more existing ones resolved. While solar keratoses and seborrheic keratoses are different conditions, they share UV exposure as a contributing factor, which makes consistent sun protection a reasonable strategy.
Practical sun protection means wearing broad-spectrum sunscreen daily on exposed skin, reapplying every two hours during prolonged outdoor time, and using hats and protective clothing. You won’t eliminate your risk, but you’ll likely slow the accumulation of UV-driven skin changes that contribute to seborrheic keratosis formation.
Can Skincare Products Help?
Retinoids, which are vitamin A derivatives, regulate how skin cells grow and shed. Small studies have explored their effect on existing seborrheic keratoses rather than prevention. In one trial, twice-daily application of a prescription retinoid cream cleared lesions completely in about half the patients treated, leaving skin that was visually and microscopically indistinguishable from normal skin. Another study found that a topical retinoic acid solution produced the best clinical improvement among several treatments tested, though it didn’t achieve complete remission.
These results suggest retinoids can help manage seborrheic keratoses that have already formed, but no study has tested whether long-term retinoid use prevents new ones from appearing. Over-the-counter retinol products promote healthy skin cell turnover, which is biologically relevant to how seborrheic keratoses develop, but calling them preventive would outrun the evidence.
What Happens if You Remove Them
Removal is straightforward when growths become bothersome, itchy, or cosmetically unwanted. Cryotherapy (freezing with liquid nitrogen) is the most common approach, though recurrence rates at treated sites range from 6% to 34%. New seborrheic keratoses can also appear in entirely different locations after removal, since the underlying genetic and age-related factors remain unchanged. Removal treats individual lesions, not the tendency to develop them.
When New Growths Deserve Attention
Most seborrheic keratoses are harmless and develop slowly over years. However, a sudden eruption of many new seborrheic keratoses within a short period, typically under a year, is known as the Leser-Trélat sign. This rare pattern can signal an internal cancer, most commonly gastric, colon, or breast adenocarcinomas, though it has also been linked to lymphomas, pancreatic cancer, and several other malignancies. About 20% of people with this sign also develop darkened, velvety skin patches in body folds.
The distinction matters: gradual development of a few new growths per year is normal aging. A rapid appearance of many lesions, especially with itching or in a “Christmas tree” pattern on the trunk, is worth having evaluated promptly.
Seborrheic keratoses can also occasionally resemble melanoma. Irregular pigmentation, uneven borders, or unusual color patterns in what looks like a seborrheic keratosis should be examined by a dermatologist. In one study of melanomas that mimicked seborrheic keratoses, nearly 87% showed irregular pigmentation and 50% had atypical pigment networks visible under magnification. If a growth changes in color, shape, or texture, or looks different from your other seborrheic keratoses, having it checked is a straightforward precaution.