What Is Cyanocobalamin/Yeast Polypeptide?
Cyanocobalamin/Yeast Polypeptide is a hybrid ingredient created by combining cyanocobalamin, a lab-stable form of vitamin B12, with short chains of amino acids extracted from yeast. By binding vitamin B12 to yeast-derived peptides, chemists improve the vitamin’s water solubility and its ability to mingle evenly throughout creams and gels. The concept emerged in the early 2000s when formulators looked for ways to harness vitamin B12’s skin benefits without the instability that pure B12 sometimes shows in lotions. Production begins with food-grade yeast that is fermented then enzymatically broken down to release its polypeptides. These peptides are reacted with cyanocobalamin in a controlled aqueous solution, followed by purification and spray-drying to yield a fine pinkish powder. Because it disperses smoothly and helps soften skin, the ingredient appears in hydrating serums, leave-on masks, anti-aging creams, after-sun lotions and soothing treatment ampoules.
Cyanocobalamin/Yeast Polypeptide’s Cosmetic Benefits/Uses
Its primary role in skincare is skin conditioning, meaning it helps improve the feel and appearance of the skin surface. By delivering moisture-binding peptides along with vitamin B12, the ingredient supports a smoother, softer complexion, reduces rough texture and may give skin a healthier tone over time.
Who Can Use Cyanocobalamin/Yeast Polypeptide
This ingredient suits most skin types including dry, balanced, combination, oily and even sensitive skin thanks to its mild nature and moisture-binding ability. It is lightweight and non-greasy so it will not weigh down oily skin, while the added peptides help comfort dryness or irritation often seen in sensitive complexions. There are no known reasons for people with mature or acne-prone skin to avoid it, although breakout-prone users should confirm the overall formula is non-comedogenic.
Cyanocobalamin/Yeast Polypeptide is produced from vitamin B12 and food-grade yeast so it does not involve animal-derived ingredients, making it suitable for vegans and vegetarians.
The ingredient is considered low risk for pregnant or breastfeeding women when applied topically because absorption through intact skin is minimal. That said this is not medical advice and anyone who is pregnant or nursing should have a quick chat with a healthcare provider before introducing new skincare just to be safe.
It does not increase photosensitivity, meaning you can use it in the morning or evening without extra risk of sunburn. Standard daytime sunscreen use is still recommended for overall skin health.
Potential Side Effects/Adverse Reactions
Side effects and reactions to the topical use of Cyanocobalamin/Yeast Polypeptide vary from person to person. The points below list potential issues yet they remain uncommon when the ingredient is properly formulated and used as directed.
- Mild redness or warmth shortly after application
- Temporary pinkish staining on very fair skin due to the natural color of vitamin B12
- Itching, hives or contact dermatitis in individuals sensitive to vitamin B12 or yeast derivatives
- Aggravation of existing irritation if layered immediately after strong exfoliating acids or retinoids
- Rare flare-up in people with a documented yeast allergy
If any persistent irritation or unusual reaction occurs stop use at once and seek guidance from a medical professional or dermatologist.
Comedogenic Rating
Rating: 0–1 out of 5. Cyanocobalamin/Yeast Polypeptide is fully water soluble, lightweight and non-occlusive, so it does not sit inside or over pores in a way that sparks congestion. It carries no heavy oils or waxy residues that typically cause blackheads.
This very low score means it is considered safe for skin that is prone to acne or frequent breakouts.
If a product containing it still feels rich the clogging potential will come from other ingredients, not this peptide-vitamin complex.
Summary
Cyanocobalamin/Yeast Polypeptide works as a skin conditioner, pairing vitamin B12 with moisture grabbing yeast peptides to soften rough patches and promote a healthier looking tone. The peptides bind water at the surface while the vitamin supports gentle renewal, together leaving skin smoother and more comfortable.
It remains a boutique ingredient found mainly in targeted serums, soothing masks and after-sun lotions rather than mass market creams, yet formulators value it for its stability and mildness.
Overall it has a strong safety profile with low rates of irritation, allergy or pore clogging when used as intended. Still, every skin is unique so perform a quick patch test when trying any new product that features this ingredient.