Lumen
Lumen Metabolism Breath Tracker
Handheld CO2 sensor that reads whether you're burning fat or carbs
Approximate price. Subject to merchant changes.
Get it on LumenAffiliate link — Regeneralive may earn a commission. We only recommend products we'd give to family.
- Serving size
- Hardware device — see manufacturer specifications
- Goal
- longevity · performance
- Category
- Wearables & Recovery Tech
The review
Why we put this on the shelf.
Lumen measures the CO2 concentration in your breath — a clinically validated proxy for whether your body is currently burning carbs or fat. Use it morning, pre-workout, post-meal to see your metabolic flexibility in real time. The most-discussed metabolic-health gadget after CGMs.
Pair it with
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