Personalized Dermato-Cosmetology: A Case Study on Biometric Skin Improvements After 28 Days of Bespoke Cosmetic

Objective: This study aimed to design and clinically evaluate a bespoke cosmetic formulation tailored to individual skin characteristics and user preferences, focusing on hydration and barrier recovery in mature, therapy-affected skin. In addition, this study aimed to explore the feasibility and short-term outcomes of a structured, biometry-driven personalization approach applied within a single-subject case study design. Materials and Methods: A personalized dermato-cosmetic formulation incorporating melatonin, astaxanthin, low-molecular-weight hyaluronic acid, allantoin, yarrow oil (Achillea millefolium), lecithin, cholesterol, and arginine was developed based on objective biophysical assessment of the skin. A clinical case evaluation was conducted in a male subject over 55 years of age (Fitzpatrick phototype III) presenting persistent xerosis and dehydration following completed oncologic therapy. Quantitative skin biometry was performed at baseline and after 28 days of daily application, assessing hydration at six anatomical sites, sebum secretion, pigmentation and erythema indices, elasticity, and stratum corneum turnover and scaling. Results: After 28 days, sebum secretion increased by more than 100%, indicating partial restoration of the lipid barrier. Hyperpigmented areas decreased from 7.2% to 2.3%, while skin elasticity improved from 25% to 44%. A reduction of 8% in the erythema index suggested decreased vascular reactivity. Hydration levels improved consistently across all evaluated sites, and epidermal renewal was enhanced, as evidenced by reduced scaling and smoother skin surface. The melanin index remained stable throughout the study period. Conclusions: This pilot evaluation shows that bespoke cosmetic formulations, customized to individual skin biometry and preferences, can yield measurable improvements in hydration, barrier repair, elasticity, pigmentation uniformity, and epidermal renewal within 28 days, even in skin compromised by previous oncologic therapy. Given the single-subject nature of this pilot evaluation, these findings cannot be generalized to broader populations but rather highlight the importance of personalization and objective skin assessment in guiding individualized dermato-cosmetic formulation strategies. Personalized dermato-cosmetology using objective biophysical assessment may be a promising future strategy for effective, consumer-centered skincare.