Lumen's research partners
100 million breaths
and counting
Join the movement toward better metabolic health.
How it works
Get tailored guidance to improve your nutrition, exercise, sleep, and stress levels for a healthier you.
Take a deep breath.
Breathe into your Lumen to get a real-time view of whether you're burning mostly fat or carbs, so you can understand the impact of your lifestyle on your metabolism.
Get the guidance that matters.
Find your balance with data-backed, personalized lifestyle and nutrition support based on your unique metabolic profile.
Reach your health goals. Lumen is your personal metabolic compass, helping improve your metabolic flexibility at every stage of life.
As seen on
Real people
real results
Lumen drives long-term, sustainable habit change that helps you reach your weight and health goals. Discover how good your body is designed to feel with Lumen.
Up to 12% of body weight
lost in just 6 months*
30% improvement
in metabolic flexibility score*
3% body fat percentage lost
on average in just 12 weeks**
Join 300K+ Lumeners
changing their lives
Manage weight
"It's like night and day. It's amazing how this device has definitely helped with losing those extra pounds."
Shakis, 35
Increase muscle mass
"I lost 23 pounds, I'm leaner than ever, I have more energy, and I eat healthier. I love it."
Ryan, 40
Improve metabolic health
"Ever since I got the Lumen, I've been able to optimize my schedule to match my metabolic needs."
Tina, 33
Increase energy
"I'm no longer so fatigued in the afternoons after I have a heavy workout day."
Heather, 52
Take your
first step
Uncover the hidden connections between your lifestyle and your health goals with our free personalized metabolic health guide, and get $20 off your Lumen!
Innovative research,
groundbreaking applications
Lumen collaborates with top institutions worldwide to conduct game-changing research about metabolism.
Lumen is the top choice for doctors and clinics putting metabolic health first
Innovative, individualized, and data-driven solutions that empower both practitioners and patients to improve metabolic health.
Learn more
FAQ
How does Lumen measure my metabolism?
When your mitochondria use carbs as fuel, they release more CO₂ into your blood, and when they burn fat, they release less CO₂. Lumen analyzes the CO₂% in your breath and determines if you are using mostly fat or carbs for fuel based on the CO₂ concentration.
Is Lumen's technology validated?
Lumen's technology is validated by multiple peer-reviewed scientific studies and is proven to measure metabolism as accurately as the gold-standard metabolic cart. Read the peer-reviewed paper.
How does metabolic flexibility improve my health?
Metabolic flexibility refers to how efficiently your mitochondria switch from burning carbs or fats for fuel, depending on their availability and your body's needs. Being metabolically flexible can be critical for disease prevention and helps with managing weight, improved insulin sensitivity, higher energy levels, better sleep, and even longevity.
Do I need the Lumen device to use the premium app features?
Yes, the Lumen device and app work together. The Lumen device measures your metabolism through your breath in real-time and the app provides personalized insights and lifestyle guidance based on those measurements.
How can I pay for Lumen using HSA/FSA?
Select "Checkout with HSA/ FSA." If you are logged into Shop Pay, please select "Check out as guest."
Complete your delivery and billing details, and then click "Pay now."
From there, enter your HSA or FSA card details and complete your checkout as usual. If you don't have your card handy, you can enter in a credit card, and Flex will send you an itemized receipt you can submit to your provider for reimbursement.
Who is Lumen for?
Lumen is for adults looking to improve their metabolic health, manage their weight, boost their energy levels, support their workout routine, and live happier and longer lives.
The Lumen app is not available for use by individuals under the age of 18.
If you are pregnant, breastfeeding, or suffer from the following conditions, please consult a medical professional before using Lumen:
Diabetes
Severe asthma
COPD
Additionally, Lumen's nutritional recommendations may not be suitable for people with:
Kidney disease
Cancer
Thyroid disorder
Is there a warranty?
Yes, we offer a one-year warranty from the date the device is delivered to you. If your device or charging dock are damaged by manufacturing defects during that period, we'll fix or replace them free of charge. You can read our full warranty policy.
* As reported in 2024 Lumen user data analysis
** https://pubmed.ncbi.nlm.nih.gov/36195053/
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