Lumen is the world’s first hand-held, portable device to accurately measure metabolism.
Lumen uses a CO2 sensor and flow meter to determine the CO2 concentration in a single breath. This indicates the type of fuel your body is using to produce energy.
The CO2 concentration is measured using a unique breath maneuver, which is performed by inhaling a fixed volume of air through the Lumen device (dynamic to each individual), holding it for 10 seconds, and exhaling fully.
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