How to use peptides in cosmetics?

The peptides are capable of influencing numerous biological mechanisms within the skin. Depending on their structure and the amino acids they contain, some peptides stimulate the production of collagen and elastin, helping to firm the skin and diminish the appearance of wrinkles, while others possess antioxidant properties that protect cells from oxidative stress. Some peptides also promote epidermal healing and regeneration, strengthen the skin barrier to better retain water and enhance hydration, or soothe inflammation and feelings of tightness. This diversity of actions explains why peptides are increasingly used in cosmetic formulations today.

How are peptides applied to the skin?

The integration of peptides into a facial skincare routine depends primarily on the type of product in which they are formulated. As with any active ingredient, it is essential to follow the supplier’s recommendations. Present in serums, creams, eye-area products, or masks, peptides are generally applied to clean skin, either before or after moisturizer depending on the product’s texture. Peptides are not photosensitizing, so they can be used both in the morning and at night, and there are no contraindications to using them concurrently with other actives such as hyaluronic acid, the niacinamide or the ceramides, nor during pregnancy or breastfeeding. A daily application, morning and night, enhances their efficacy.

Peptides are also of great interest for hair. Some studies suggest that they may stimulate proliferation of hair follicle cells and activate the Wnt/β-catenin and GSK-3β/β-catenin biological pathways involved in the hair growth cycle. Peptides may also promote the expression of growth factors such as IGF-1 or VEGF, which are essential for proper follicle function. However, caution is warranted: most of these observations come from in vitro, and their real effectiveness on hair growth remains to be confirmed. Their role in hair fiber repair is better documented. Peptides, particularly those derived from collagen, help strengthen keratin, smooth the cuticle, and improve hair elasticity and shine.

How are peptides utilized in hair care applications?

As with skin, the use of peptides in hair care depends on the type of product selected. Serums and leave-in lotions are applied directly to a clean scalp, gently massaging to promote penetration, while peptide-enriched masks and conditioners are used after washing, with application times varying according to the formula. There are also peptide-based shampoos, which are used like a classic shampoo. However, if their aim is to strengthen hair growth, we recommend that you leave it on for a few minutes, allowing the active ingredients time to penetrate the scalp.

Orally administered peptides, particularly collagen peptides, are currently the focus of extensive research for their effects on the skin. Several clinical trials have shown that regular collagen peptide supplementation significantly improves hydration, elasticity, and skin barrier function, while reducing roughness and wrinkle depth. These effects rely on stimulating endogenous collagen and hyaluronic acid synthesis, as well as on better organization of collagen fibers in the dermis. The ingested peptides also exert antioxidant and anti-inflammatory actions, contributing to the protection of the skin from oxidative stress and UV-induced damage, two mechanisms at the core of skin aging.

How are peptides administered orally?

The administration protocol for oral peptides depends on the type of supplement chosen, but most clinical studies employ a daily dose of 2.5 to 10 g of collagen peptides for at least 8 to 12 weeks to observe noticeable effects. Supplements are often available as powders, capsules, or beverages to be consumed once daily, preferably at a consistent time. However, as with any dietary supplement, it is advisable to consult a physician before beginning supplementation, especially in cases of illness, pregnancy, or concurrent medication, to ensure compatibility and safety of use.

Injectable peptides represent a recent innovation in aesthetic dermatology, particularly when used in synergy with botulinum toxin (botox). Their value lies in their ability to enhance the effects of neurotoxins while delivering complementary benefits depending on the peptide used: wrinkle reduction, improved skin radiance, and strengthened overall skin quality. Peptide injections can also be used on the scalp to stimulate hair growth, or even combating alopecia.

How are peptides administered via injection?

Peptide injections are performed exclusively in a medical office under the supervision of a qualified professional.

Just as with hyaluronic acid injections, peptide injections are relatively quick and painless, lasting only about ten minutes. They can cause mild redness, swelling, or small bruises, which generally fade within a few days. The number of sessions depends on the desired outcome. To reduce wrinkle visibility, 3 to 4 sessions spaced 2 to 3 weeks apart are typically recommended. In cases of alopecia, 5 to 7 sessions may be necessary, initially spaced two weeks apart and then one month apart. Results appear gradually over the sessions, as peptides exert their biological effects on the tissues.

Note: Peptide injections are not suitable for everyone. Pregnant or nursing women, individuals with bleeding disorders, or those with an active skin condition such as acne, for example, cannot receive these injections. In any case, a prior medical evaluation is necessary to ensure the safety and appropriateness of this type of procedure.

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