Lumen is a device that measures metabolism in real time and tells users whether they are burning fats or carbs and what they can do about it.

Lumen also includes an application that acts as a virtual nutritionist, providing dietary and exercise recommendations based on the user's metabolism.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 the body is using to produce energy.The platform provides users with a daily personalized nutrition plan and insights into how different foods affect them.

It can also assess whether users have enough available energy to work out.Lumen was developed by Meta Flow.