When Antoine (Po-Han) Ho arrived at Stanford School of Medicine as a Skin Longevity Program Fellow and New Map of Life Fellow, he brought an unusual combination of credentials — board-certified dermatologist from Taiwan, Harvard-trained public health researcher and former biopharma consultant. But it was a single question that guides his fellowship: Can the skin, the body’s largest and most visible organ, serve as a window into how we age from the inside out? 

Working under Professor Anne Lynn S. Chang in Stanford’s Department of Dermatology, Ho set out to build something that doesn’t yet exist in clinical medicine — a standardized, validated tool for measuring “skin frailty.” The term itself is not a diagnosis found in any medical coding system. As Ho explains, dermatologists encounter its manifestations — easy bruising, fragile tissue, slow-healing wounds — but without a reliable framework for assessing them. His fellowship work has been an act of definition: building the vocabulary and metrics for a condition hiding in plain sight.

“What we are trying to do,” says Ho, “is to see if skin can be an indicator, not just of how aging affects your skin, but also the whole body.”

The science behind his hypothesis is grounded in biology. Type I collagen is the predominant collagen subtype in both skin and bone, raising the possibility that collagen loss in one tissue may parallel changes in the other. In addition, elastic fibers are important components of the extracellular matrix in both cutaneous and cardiovascular tissues. Furthermore, skin cells have been utilized as cellular models for studying neurodegenerative diseases due to shared molecular and mitochondrial aging pathways. These biological parallels point toward a larger idea: that accelerated skin aging might signal accelerated aging elsewhere in the body, from bones to blood vessels to the brain.

“We are trying to decipher if a standardized assessment tool for skin frailty can correlate with different kinds of comorbidities,” Ho says.

Ho’s research, which has been supported by several members of Dr. Chang’s research group, has unfolded in several phases. An initial pilot study of approximately 200 participants established correlations between skin frailty scores and age, sex and skin cancer risk. Now, a larger 2,000-person cohort — roughly 1,200 enrolled at the time of this writing — is underway, designed to test whether those scores also correlate with systemic conditions like osteoporosis, cardiovascular disease, and neurodegenerative disorders such as memory loss. (To volunteer to participate in the study, contact [email protected].)

Alongside this clinical research, Ho has been building a standardized image library labeled with skin frailty scores, collaborating with an industry partner to train machine-learning algorithms capable of automated assessment from digital photographs. The goal is scalability: a low-cost, noninvasive screening tool accessible far beyond the dermatology clinic.

Ho is careful not to overstate where the science stands. Proving correlation is the first step; proving causality and identifying interventions that might prevent both skin frailty and its associated systemic health problems will require years of further study. But the direction of his work represents a meaningful shift — away from aging skin as primarily a cosmetic concern and toward skin as a health indicator.

As his fellowship concludes, Ho is preparing for his U.S. medical licensing exams and is eager to combine research with clinical practice. The patients he hopes to see, he says, will inspire his next set of research questions.

—Tamara Straus