What Is Sh-Polypeptide-29?
Sh-Polypeptide-29 is a lab-made version of human Interleukin-3, a naturally occurring signaling protein. Scientists recreate the exact genetic code of Interleukin-3 then insert it into harmless E. coli bacteria. During fermentation the bacteria act like tiny factories, producing the peptide in large amounts. Afterward the mixture is filtered and purified to remove bacterial material, leaving a clean single-chain protein of up to 152 amino acids. Some molecules may link by disulfide bonds or pick up small sugar groups, both of which help stabilize the structure.
The cosmetic world began exploring bio-engineered peptides in the early 2000s when brands looked for gentler, targeted ways to support skin. Because Interleukin-3 is involved in cell communication researchers wondered if a topical form could encourage smoother, healthier looking skin. Once production methods became cost-effective, Sh-Polypeptide-29 started appearing in premium skincare.
Today you will most often see it in leave-on formulas such as anti-aging serums, lightweight moisturizers, sheet masks and concentrated eye treatments. Its job is to condition skin so it feels soft, looks more even and stays resilient against daily stress.
Sh-Polypeptide-29’s Cosmetic Benefits/Uses
In skincare Sh-Polypeptide-29 is valued for one primary function, which is skin conditioning. By sitting on the surface and interacting with the upper layers, it helps skin feel smoother, look more supple and maintain better moisture balance. Over time a conditioned skin barrier can appear less dull and more refined, making this peptide a useful addition to products aimed at revitalizing tired or mature complexions.
Who Can Use Sh-Polypeptide-29
Sh-Polypeptide-29 is lightweight and water based, so it suits most skin types including dry, oily, combination and sensitive. Because it is non-occlusive it will not overwhelm oily or acne-prone complexions, while its conditioning effect can support drier or more mature skin. The main group that may wish to avoid it are individuals with a known sensitivity to proteins or fermentation derived ingredients, as they could react to even highly purified peptides.
The peptide is produced in bacteria without any animal-derived material, making it appropriate for vegans and vegetarians. Manufacturers typically confirm this status through supplier documentation.
There is no research indicating that topical Sh-Polypeptide-29 poses a risk for pregnant or breastfeeding women, yet formal safety testing in these groups is limited. This content is not medical advice, and anyone who is pregnant or nursing should have their healthcare provider review any skincare product they plan to use.
Sh-Polypeptide-29 is not known to cause photosensitivity, so it can be applied morning or night. Standard daytime sun protection is still recommended, but additional sun care steps are not required specifically because of this peptide.
Potential Side Effects/Adverse Reactions
Side effects from topical use of Sh-Polypeptide-29 vary from person to person. The points below outline potential reactions, though most users will not experience them when the ingredient is properly formulated and used as directed.
- Mild temporary redness or warmth shortly after application
- Itching or a prickling sensation in very sensitive skin
- Localized rash or contact dermatitis in individuals allergic to proteins or fermentation residues
- Stinging on compromised or freshly exfoliated skin
- Rare breakout flare if combined with a comedogenic base formula
If any of these effects occur discontinue use and consult a healthcare professional if symptoms persist or worsen.
Comedogenic Rating
Rating: 0 / 5
Sh-Polypeptide-29 is a pure, water soluble peptide with no heavy oils or waxes that could clog pores. It sits on the surface, conditions skin then rinses or wears away without leaving residue inside follicles. Because it is made of amino acids that are naturally found in skin, the risk of pore blockage is considered negligible.
That makes it suitable for people who are prone to acne or frequent breakouts.
One thing to watch is the full formula it appears in. If the finished product pairs the peptide with richer emollients or silicones, the overall pore-clogging risk could go up even though the peptide itself is non-comedogenic.
Summary
Sh-Polypeptide-29 is a lab made copy of human Interleukin-3 used in skincare to condition skin so it feels smoother, looks more supple and holds moisture better. It delivers these benefits by forming a lightweight protein layer that supports the surface cells and keeps water from escaping too quickly.
The ingredient shows up mostly in higher end serums, masks and eye creams, so it is not as common as classic hydrators like hyaluronic acid. Brands that want a science-forward edge often choose it to stand out in crowded anti-aging lines.
Safety data so far is reassuring with low reports of irritation or allergy and a comedogenic rating of 0. Still every formula is different. When you try a new product that contains Sh-Polypeptide-29 apply a small amount on a test area first to make sure your skin agrees with it.