Peptides are short chains of amino acids that act as biological messengers within the body. In cosmetics, they are used to superficially stimulate collagen production in the skin. Outside of a medical context, purchasing so-called "miracle" peptides online (for sports or weight loss) poses serious health risks highlighted by the ANSM (French National Agency for the Safety of Medicines and Health Products). Definition and natural role: They are protein fragments—smaller than proteins themselves—made up of a few linked amino acids. They transmit signals to cells to regulate various physiological functions (such as insulin, which is a natural peptide).
Use in cosmetics: When incorporated into creams (such as anti-aging products), the smoothing effect is usually limited to the surface of the epidermis. Deep penetration through the skin barrier is chemically difficult due to their molecular size. The actual benefits observed in short-term clinical studies remain modest. Risks associated with online purchases and social media: Self-medication or the online purchase of peptides marketed for weight loss or muscle building is strongly discouraged by health authorities. Fraudulent or unregulated injectable products carry risks of infection, severe digestive disorders, or liver damage. Many compounds sold under the guise of "research" lack validation for human use and are illegal.
