What Is Sh-Polypeptide-25?
Sh-Polypeptide-25 is a lab engineered version of the protein Interleukin-2, created through recombinant DNA technology. Scientists insert a synthesized human gene that codes for Interleukin-2 into E. coli bacteria, allow the bacteria to ferment and produce the peptide, then purify the resulting protein. The finished ingredient is a single chain of up to 153 amino acids and may include natural features like disulfide bonds or light sugar attachments, mirroring what occurs in the body. Interest in bioidentical peptides grew in the late 1990s as skin care brands searched for actives that could signal healthier looking skin without irritation. Advances in fermentation and purification made it cost effective, and formulators soon began adding Sh-Polypeptide-25 to serums, anti aging creams, soothing masks, post-procedure gels and daily moisturizers that promise smoother, more resilient skin.
Sh-Polypeptide-25’s Cosmetic Benefits/Uses
This ingredient is valued for a single core benefit in topical formulas.
As a skin conditioning agent, Sh-Polypeptide-25 helps improve the overall feel and appearance of the skin. It attracts water to the surface, supports a stronger moisture barrier, and can leave the complexion feeling softer, calmer and more supple. Over time consistent use can promote a smoother texture and a healthier looking glow.
Who Can Use Sh-Polypeptide-25
Sh-Polypeptide-25 is generally suitable for all skin types including dry, oily, combination and sensitive. Its primary role is to condition and hydrate rather than exfoliate or heavily occlude so most people can tolerate it well. Those with extremely reactive or allergy-prone skin should still review the full ingredient list of the finished product to make sure there are no additional triggers.
The peptide is produced through bacterial fermentation with no animal-derived substances, making it appropriate for vegans and vegetarians.
Current data does not indicate any special risk for pregnant or breastfeeding individuals when Sh-Polypeptide-25 is used topically in typical cosmetic concentrations. This is not medical advice; anyone who is expecting or nursing should run their skincare routine past a qualified physician to be safe.
The ingredient does not increase photosensitivity so it will not make skin more prone to sunburn. Standard daily sunscreen use is still recommended as part of a healthy routine.
Potential Side Effects/Adverse Reactions
Side effects and reactions to the topical application of Sh-Polypeptide-25 can vary from person to person. The points below outline potential issues yet they are uncommon when the ingredient is formulated and used correctly.
- Mild redness or warmth: A temporary flush can appear in very sensitive skin, usually subsiding quickly once the product is absorbed
- Itching or stinging: Rare but possible, especially if the formula contains additional actives that lower skin pH
- Allergic contact dermatitis: Although Sh-Polypeptide-25 is bioidentical, an individual could still develop a localized allergic response characterized by swelling, rash or persistent irritation
- Breakouts in acne-prone users: Not caused by the peptide itself but by richer bases that sometimes accompany peptide serums or creams
If any persistent or severe reaction occurs discontinue use and seek advice from a dermatologist or healthcare professional.
Comedogenic Rating
Rating: 0/5
Sh-Polypeptide-25 is a large water-soluble protein that sits on the surface of the skin instead of seeping into pores and hardening, so it is considered non-comedogenic. It contains no oils or waxy fatty acids that typically trigger blockages. This makes the peptide suitable for people prone to acne or frequent breakouts. Keep in mind that the overall formula can change pore-clogging potential, so rich creams or heavy occlusives paired with the peptide may still cause issues for some users.
Summary
Sh-Polypeptide-25 is a bioidentical version of Interleukin-2 created through fermentation in E. coli. In skin care it works as a conditioning agent that boosts surface hydration, supports a healthier moisture barrier and leaves skin feeling smoother and calmer. While not as famous as collagen or retinol, it is gaining a steady following among brands that focus on peptide technology and gentle barrier support. Topical use shows a strong safety profile with very low risk of irritation or pore clogging, yet anyone trying a new product should still perform a quick patch test to rule out individual sensitivities.