The Thinking Behind Prysm iO
This page explains, in everyday language, what Prysm iO measures, where the technology comes from and where its limits lie. It is written to help you decide whether the device is something you would like to explore, not to make claims about anyone's health.
What Is Being Measured
Carotenoids are natural pigments found in colorful fruit and vegetables, and some of them are stored in the skin. Prysm iO shines light onto a fingertip and uses the way that light is absorbed and reflected to estimate skin carotenoid levels. The estimate is turned into a single Prysm Score, which the companion app records so that a person can see how it changes between scans.
Because the reading is an estimate, a single scan is best treated as a snapshot. The pattern across several scans, taken the same way, is more useful as a conversation point than any one figure.
Where the Method Comes From
Measuring skin carotenoids with light has been explored by university research groups in nutrition studies for well over a decade. One example is a 2013 review by researchers at a US university school of public health, listed on PubMed. We point to it as background reading only; it does not describe Prysm iO itself, and you should read it for yourself and form your own view.
Prysm iO is the latest generation of a line of scanners that began with Pharmanex in 1999. Earlier devices read the palm and took longer to run. Prysm iO reads a fingertip and uses a different light-based method, with an algorithm turning more than 700,000 separate light measurements into one score. More than 25 million scans have been performed worldwide on earlier-generation devices.
What It Does Not Do
- It is not a medical device and is not part of any dental examination.
- It makes no statement about the mouth or any oral condition.
- It does not diagnose, treat or screen for any condition.
- It does not tell anyone what to take. Any supplement a patient's physician or other healthcare provider has recommended should only be changed with that provider's agreement.
Recognition
Prysm iO has received recognition from outside Nu Skin's own organization:
- 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 Money-Back Policy
Nu Skin designates certain products as “Prysm Certified” and offers a money-back policy on them: if a person's score has not improved after 90-100 days on a certified, Prysm-eligible product, the purchase can be refunded, subject to Nu Skin's Terms and Conditions. Please read the terms that apply in your market.
Prysm iO is a wellness insight tool. It is not intended to diagnose, treat, cure, prevent, or mitigate any disease or medical condition, and it is not a substitute for a dental examination or medical advice.