Health technology · Irvine, California · Since 1998

Advancing technology for prevention. Transforming care.

We build digital tools and noninvasive sensing technology that support healthy habits and metabolic health, grounded in more than two decades of research.

Nutu ScoreIn the green zone

Nudge: add a protein to lunch to stay balanced this afternoon.

1998Founded in Irvine, California, by Joe Kiani
Since 2005Rainbow® Technology in hospital monitoring products
8Parameters measured noninvasively by Rainbow
DPPNutu’s Diabetes Prevention Program, with preliminary CDC recognition
The technology underneath

Rainbow® Technology. Many wavelengths of light, one sensor.

Our patented multi-wavelength platform measures eight parameters noninvasively, including hemoglobin and its variants. It has been used in hospital monitoring products since 2005. Ember and Nutu are consumer products and are not the hospital monitoring products described here.

How Rainbow works
  • SpO2Oxygen saturation
  • PRPulse rate
  • PIPerfusion index
  • SpHbTotal hemoglobin
  • SpOCOxygen content
  • SpMetMethemoglobin
  • SpCOCarboxyhemoglobin
  • PViPleth variability index
Our mission

Improving healthspan and lifespan by innovating therapeutic care.

Willow Laboratories was founded in 1998 by Joe Kiani, who also founded Masimo and co-invented measure-through-motion pulse oximetry. We began as Masimo Laboratories, a spinoff of Masimo, and were later Cercacor Laboratories. Today we apply that sensing heritage to healthy habits and metabolic health.

Meet the team
As featured in
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Bring Nutu to your members, patients or employees.

We work with health plans, employers and providers on population health. Tell us what you are trying to solve.