How Lumen works

The science isn’t new but the technology is.

It starts with a breath

The Lumen device 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.

into Lumen


Getting to know you

Lumen is calibrated to your unique CO2 range and lung capacity.

Taking a morning breath

Each morning, Lumen determines the source of your body’s fuel — carbs or fats.

Receiving your plan

Lumen provides personalized nutrition recommendations and daily guidance on sleep, diet, exercise and more.

How do you measure metabolism?

Before Lumen

The only way to measure your metabolism was in a hospital or clinic with a costly and time-consuming test known as RQ (a measurement through the blood) or RER (through the breath).


Lumen uses RER as the core data point to bring the same measurement to a home environment by measuring the CO2 in your breath through the sensor and flow meter, based on the RER metric.

Real-time accuracy

In multiple studies, Lumen’s patent-pending technology was deemed to accurately measure metabolic fuel usage when compared to the gold standard RQ for measuring metabolism.
Learn more about Metabolism

Hear From Real Lumen Users

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