There are thousands of known peptides, and they come in a variety of forms. They are used in injectables (you're likely familiar with GLP-1, like Ozempic or Wegovy), in hair growth products, and are increasingly being used in skincare.
In fact, a peptide revolution of sorts has occurred on beauty store shelves: a plethora of serums and creams using cellular messengers have appeared, promising to improve firmness, strengthen the skin barrier, and reduce the appearance of fine lines—with less risk of inflammation or irritation than retinoids. "Peptides are generally well-tolerated and can be a useful addition to skincare, especially for people who have difficulty tolerating stronger active ingredients like retinoids," explains consultant dermatologist Dr. Derrick Phillips.
The use of retinoids in skincare is nothing new. Vitamin A derivatives are the most studied topical ingredient in dermatology, with over 50 years of proven experience and data. Retinol, a type of retinoid, is used to stimulate cell turnover and collagen production. "It's widely used in skincare products to improve uneven tone and texture, smooth fine lines, and reduce the appearance of acne scars and enlarged pores," says Dr. Phillips. So which is better for rejuvenating, firming, and regenerating skin? Experts tell us all.
Peptides vs. Retinol: What's the Difference?
"Both peptides and retinol can promote smoother, firmer skin, but they work differently," explains Dr. Phillips. "Peptides are short chains of amino acids that can act as signaling molecules in the skin. Depending on the type, they can support collagen production, hydration, or the skin barrier." Retinol is a vitamin A derivative that increases skin cell turnover and stimulates collagen production, and there's strong evidence for its effectiveness in improving skin condition, evening out texture, and reducing acne scars. There's ample scientific evidence supporting retinol's effectiveness in reducing the appearance of fine lines. Peptides haven't been studied as thoroughly, but Dr. Phillips believes they can also "support collagen production and improve the appearance of fine lines."
As for choosing one over another, the expert explains that it all comes down to tolerability and side effects. "Retinol is generally more effective, but it's also more likely to cause dryness, redness, and flaking, especially initially. Peptides are generally gentler and may be a better option for those with sensitive or reactive skin." For those with sensitive skin, eczema, or rosacea, it might seem like retinol should be avoided entirely, but Dr. Phillips says this isn't the case unless you're experiencing an active flare-up. He emphasizes that introducing retinol should be careful and deliberate.
How long does it typically take to see results from peptides versus retinol?
In short, it depends on many factors. Dr. Phillips says that regardless of the ingredient used, results depend on "the formula, concentration, and frequency of application." Moreover, they work differently, which also affects the time frame. "With retinol, some people may notice improvements in skin texture and radiance within four to six weeks, although changes in fine lines and firmness typically take several months." Peptides, on the other hand, act more gently. "A hydrating effect or improved skin barrier function may be noticeable within a few weeks, while improved firmness or a reduction in fine lines may take eight to twelve weeks or longer." He emphasizes that consistency is key to success.
What are the most common side effects of retinol and peptides?
If you've used retinol before, you're likely familiar with its side effects, which can include dryness, flaking, or redness. This is very common. Dr. Ellie Rashid, a consultant dermatologist at CeraVe, confirms this, explaining that dryness, tightness, flaking, and mild irritation, as well as temporary redness or increased sensitivity, are likely, especially if you "start with too much strength or use it too often." She also wants to clarify that "there are various over-the-counter topical retinoids: granular retinoids, retinyl esters, retinol, and retinaldehyde (retinal)," all of which have different concentrations.
In contrast, peptides are generally well-tolerated, making them a popular alternative to retinol. "Most people can use them without irritation," says Dr. Rashid.
When should you start adding each ingredient to your skincare routine?
"I don't think there's a specific age when everyone should start," says Dr. Rashid of retinol. "It depends more on your skin concerns." She clarifies that those with acne, pigmentation, fine lines, or changes in skin texture may benefit from incorporating retinol into their routine, adding that this typically begins in their twenties. Peptides, on the other hand, are ideal for starting at the first signs of skin aging. "They can be especially helpful if you're noticing early signs of aging, want to support collagen production, or are trying to strengthen the skin barrier alongside more active ingredients," adds Dr. Rashid.
Can peptides and retinol be used together? What's the best order to apply them?
In fact, these two ingredients work very well together, especially because peptides support the skin barrier, which can be compromised by retinol. Dr. Rashid explains, "Retinoids stimulate collagen production and accelerate cell turnover, but they can also temporarily weaken the skin barrier while the skin adapts. Peptides can help support skin repair and barrier function, making them an excellent addition."
For maximum effectiveness, apply peptides after retinol. "If you're using different products, I typically apply retinol to cleansed skin first, followed by a peptide-based moisturizer," says the expert. "But if you experience irritation or if you have particularly sensitive skin, you can also use a 'retinol sandwich' approach, applying moisturizer before and after retinol to reduce irritation."
What should you look for when choosing a retinol?
A common mistake is to assume that the highest concentration of retinol is the most effective. This is far from the right approach. "The most important thing isn't necessarily to choose the strongest retinol; it's to choose one that you can actually use consistently," says the dermatologist. Instead, look for formulas that combine retinol with skin-friendly ingredients. Dr. Rashid recommends "hydrating and barrier-supporting ingredients like ceramides, hyaluronic acid, and glycerin." She also advises looking for encapsulated retinol, which "may also improve stability and reduce irritation."
When starting to use retinol, take a gradual approach to give your skin a chance to adapt. "My advice is to always start with a lower concentration two to three times a week, gradually increasing the frequency of use as your skin adapts," advises the dermatologist. "Consistency over several months is much more important than using an aggressive product that causes too much irritation to continue."
What should you look for when choosing a peptide skincare product?
"Not all peptides are created equal," the dermatologist emphasizes. So, before investing in a skincare product, it's worth researching the one that best addresses your concerns—there's a huge selection. "Different peptides perform different functions, from supporting collagen production to improving hydration or reducing the appearance of fine lines." But while the peptide itself is important, the formula is equally important. "Look for products that contain well-researched peptides along with barrier-supporting ingredients like ceramides, cholesterol, and humectants."
What are the most common mistakes people make when using these ingredients?
Retinol is photosensitive, so it should be used at night, and sunscreen should be applied the following morning. "A common mistake is forgetting to apply sunscreen daily," concludes Dr. Rashid. "Retinoids can make skin more susceptible to UV damage."
