Lumen is the world’s first hand-held, portable device to accurately measure metabolism. Lumen measures your metabolism in a single breath and helps you lose weight and optimize your workouts. From metabolic tracking to personalized nutrition plans, Lumen is an effortless metabolic tracking and wellness coach all in the palm of your hand! Once available only to top athletes, in hospitals and clinics, metabolic testing is now available to everyone. With Lumen's daily insights, you will improve your metabolism by improving metabolic flexibility: your body's ability to shift efficiently between using fats or carbs as a source of energy