What Sits Behind Prysm iO

Skin Carotenoids in the Academic Literature

Measuring carotenoids through the skin has been explored for many years by university research groups, including a team at the Yale School of Public Health working with physicists from the University of Utah, who built early optical instruments for the purpose.

In 2013 the Yale group published a review in Archives of Biochemistry and Biophysics that gathered their own studies together with the wider literature on resonance Raman spectroscopy of skin carotenoids. The review discusses skin carotenoid levels as a marker that researchers can use in human nutrition studies, and it also notes that diet explains only part of the variation seen between people and that larger studies were needed.

Mayne ST, Cartmel B, Scarmo S, Jahns L, Ermakov IV, Gellermann W. “Resonance Raman spectroscopic evaluation of skin carotenoids as a biomarker of carotenoid status for human studies.” Arch Biochem Biophys. 2013;539(2):163-70. PubMed

That body of work concerns earlier research instruments and the general approach, not Prysm iO specifically. It is useful context for why a skin carotenoid reading is of interest, and it should not be read as evidence about what any score means for an individual patient's health.

Research on Prysm iO Itself

Nu Skin runs its own research program on Prysm iO. The company has described a comparison of Prysm iO readings with an earlier Pharmanex scanner and with another measure of carotenoids, along with a pilot project involving Stanford Medicine and further university studies that it says are underway.

Please weigh this accordingly: the work is funded or reported by the manufacturer, some of it is early-stage, and full results from the pilot are not yet published. This site does not quote figures from unpublished work. Readers who want the detail can look at Nu Skin's December 2025 launch announcement and at the paper that compares Prysm iO with the earlier BioPhotonic Scanner S3, which is available here. The study behind that paper was funded by NSE Products, the maker of Prysm iO, and Brigham Young University.

As with any measuring device, individual readings can vary. A single scan is best treated as a snapshot, and a trend across repeated scans taken the same way is the more useful thing to look at.

Recognition From Outside Nu Skin

Prysm iO has also received recognition from award programs that are separate from Nu Skin's own research:

• Achievement in Technology Innovation - TITAN Business Awards (winner page)
• Best of Category, Wellness Insight - Globee Business Awards
• Personal category winner - Good Design Awards 2025 (project page)

Prysm Certified Products and the Score Guarantee

Nu Skin labels certain products “Prysm Certified,” meaning the company designed them with the aim of raising a person's Prysm Score over time. It backs this with a money-back guarantee: if a score has not improved after 90-100 days on a certified, Prysm-eligible product, the purchase is refundable, subject to Nu Skin's Terms and Conditions. A guarantee is a statement about the purchase, not a statement about anyone's health.

Two Decades of Development

Prysm iO is the fourth generation in a line of scanners that began in 1999 with the first Pharmanex Biophotonic Scanner, a room-sized machine that took around an hour to calibrate. A smaller, portable version followed in 2002, using Raman spectroscopy, a technique that goes back roughly a century to the physicist C.V. Raman. The S1 launched commercially in 2003, the S2 in 2006 and the S3 in 2013, with Bluetooth and 30-second scans, eventually reaching 51 countries and more than 25 million scans.

Prysm iO is a new generation rather than a repackaged S3. It scans from a fingertip instead of the palm and relies on a different method: patent-pending “spectral ray” technology that reads how skin absorbs and reflects hundreds of thousands of light measurements per scan, similar in principle to a pulse oximeter. Its AI-driven scoring algorithm still refers back to the underlying Raman research. What carries over from earlier generations is more than 20 years of development work and the experience of millions of scans.