Lumen Metabolism Tracker Review + Discount Code

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Key Information

Lumen measures your metabolism by analyzing your breath

Lumen tells you how your body uses fat and carbs for energy based on the CO2 levels in your breath.

Lumen helps you optimize your diet and lifestyle

Lumen gives you personalized nutrition and fitness recommendations based on your metabolic state and goals.

Lumen is easy to use and affordable

Lumen is a portable device that connects to a smartphone app. You just need to blow in the device for 10 seconds and get instant feedback.

Lumen is backed by science and validated by independent tests

Lumen uses the same method as a laboratory setup to measure the respiratory exchange rate (RER). Lumen has been proven to be accurate and reliable by several studies.

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Metabolism is a crucial component of mind-body wellness.

If you’ve ever felt “HANGRY,” then you understand.

You go a long time without food, and your blood sugar eventually drops, leaving you physically hungry and mentally incapacitated.

This hypoglycemic reaction makes you irritable and unable to think.

For those who are metabolically flexible, this doesn’t happen often.

For others, this blood sugar roller coaster can make life miserable.

The good news is that you can get off the roller coaster with the proper dietary habits and stabilize your blood sugar and, ultimately, your metabolism.

However, this goes far beyond just “eating healthy.”

Everyone reacts differently to certain foods, which is why you need a reliable way to track how different foods affect you.

The Lumen Handheld Metabolism Tracker is an affordable, easy-to-use device that does just that.

The following review discusses what the Lumen is, how it works, and my personal experience using this game-changing technology.

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Frequently Asked Questions

What is the lumen metabolism tracker, and how does it work?

The Lumen Metabolism Tracker is a device developed by Metaflow LTD that measures your body’s metabolic state by analyzing the levels of carbohydrates and fats in your breath. This information can help you better understand how your body uses energy, and optimize your diet and exercise routine based on this understanding.

How is the lumen metabolism tracker different from other fitness trackers?

Unlike most fitness trackers, which only measure basic physical activity such as steps taken or distance traveled, lumen directly measures the metabolic processes that determine how our bodies burn energy for fuel. This allows users to get a much more detailed picture of their metabolism and create tailored plans to optimize their health and wellness goals.

How accurate is the lumen metabolism tracker in measuring metabolic state?

The exact accuracy of the lumen metabolism tracker will depend on the individual user, as factors like body type, lifestyle habits, and recent health conditions can affect results. However, most users have found that it provides a fairly accurate reading of what is going on inside their bodies when it comes to burning fat versus carbs for fuel.

How can I use my results from using the lumen metabolism tracker to improve my health?

Once you have an understanding of your body’s metabolic state based on your breath analysis with lumen, you can use this information to adjust your diet or exercise routine accordingly in order to reach your specific health goals more effectively. For example, if you find that your body is primarily burning carbohydrates for energy rather than fat, you might want to focus on eating more lean proteins or healthy fats in order to increase fat burning instead. You could also consider incorporating more high-intensity interval training into your workout routine in order to boost overall calorie burn after each session.

How often should I use my lumen metabolism tracker? Is there any special preparation required before each measurement session?

In general, you will want to use your Lumen tracker at least once per day so that you can monitor patterns in your metabolic status over time and make adjustments as needed. Most users find that taking measurements first thing in the morning before eating or drinking anything is best for getting reliable results. You may also need to take some short breaths before each measurement session according to the instructions provided by your device’s app or user manual.

What Is Lumen?

Lumen is a metabolism tracker device that works by reading the CO2 concentration in your breath to help you understand how your body works.

By reading your breath, Lumen tells you how your body fared from the food you ate.

You can track these metrics throughout the day for accurate readings.

After a meal, you can track your body’s response to the specific foods you ate, while in the morning you can see your baseline for the day.  Lumen will even give you a personalized nutrition plan to help you better optimize your diet.

Over the 4-week tracking period, Lumen understands your body well enough to give you a comprehensive reading and plan to help you maximize the food you eat.

How Lumen Works

Lumen reads the CO2 concentration in your breath to determine whether you are burning fat or carbohydrates.

Simply blow in the device at different times of the day to discover how your body reacts to different foods and activities.

The smartphone app interprets everything in an easy-to-understand format and gives you tips on dietary adjustments to optimize your metabolism.

It’s like having a nutritionist on demand.

Physical device

The physical device looks like a big pipe you blow on to get your breath CO2 analyzed by the companion app.

Unlock your day by breathing on the device. Continue doing so before and after a workout or a meal.



The companion app, Lumen – Metabolism Tracker, is available on Google Play and App Store. It works in tandem with the device, and it gives you real-time reports on your metabolic health. It’s like having a nutritionist and a lab right in your very own home.

It tracks your daily metabolism, creates customized meal plans, informs you if you have enough energy to burn during a workout and improve your metabolic flexibility.1Bret H. Goodpaster, Ph.D. and Lauren M. Sparks, Ph.D., Metabolic flexibility in health and disease Cell Metab. 20182Reuben L Smith, Maarten R Soeters, Rob C I Wüst, and Riekelt H Houtkooper, Metabolic Flexibility as an Adaptation to Energy Resources and Requirements in Health and Disease Endocr Rev. 2018

Metabolic flexibility allows you to shift from one energy source (fat) to the other (carbs) so you can have a balanced meal every time without skipping on some food you love.

lumen nutrition plan

Lumen is a tool designed to provide a personalized nutrition plan to achieve optimal health. The developers hope to include a wide range of medical illnesses and diseases in the future and will need an FDA-certification for that.

Using machine (device) and AI (app) learning, Lumen combines proper measuring tools for breath measurements, keeping data of your activity and food intake, and using these data to recommend a personalized meal plan to improve your overall health.

Science Behind Lumen

To establish an individualized meal plan, scientists and engineers at Lumen developed technology to track your metabolic health by analyzing the CO2 levels of your breath.

Instead of spending hundreds of dollars on a single RER test in the hospital, you can now blow your breath for 10 seconds into the device, and voila! You have real-time reading on your mobile app.

The respiratory exchange rate (RER) shows the muscle’s capacity to get energy. High RER values indicate a sedate lifestyle, using mostly carbs as an energy source.

On the other hand, a lower RER shows that the body uses fat as an energy source. Lower RER also increases insulin sensitivity and helps in whole-body fat oxidation.3Arnulfo Ramos-Jiménez, Rosa P. Hernández-Torres, Patricia V. Torres-Durán,3 Jaime Romero-Gonzalez, Dieter Mascher, Carlos Posadas-Romero, and Marco A. Juárez-Oropeza, The Respiratory Exchange Ratio is Associated with Fitness Indicators Both in Trained and Untrained Men: A Possible Application for People with Reduced Exercise Tolerance Clin Med Circ Respirat Pulm Med. 2008

Read more scientific researches conducted to validate the effectiveness of Lumen Metabolism Tracker.

How Does Lumen Determine Metabolism

Respiration quotient (RQ) is the volume of carbon dioxide released over the volume of oxygen absorbed during respiration. Clinicians use this number in calculating the basal metabolic rate. Although they measure the same CO2 release vs. O2 uptake, RQ uses a more invasive method since it targets the tissue compared to RER’s breath analysis.

Carbohydrates show the biggest RQ of 1.0, while fats show the lowest at 0.7. Close behind carbs are proteins at 0.9.4Hiran Patel; Connor C. Kerndt; Abhishek Bhardwaj., Physiology, Respiratory Quotient StatPearls Publishing; 20205Stephen A McClave,Cynthia C Lowen,Melissa J Kleber,J Wesley McConnell, Clinical use of the respiratory quotient obtained from indirect calorimetry Journal of Parenteral and Enteral Nutrition. 2003

Using these numbers, Lumen measures your metrics and compares them with the gold standards RQ levels.6Karl J. Kaiyala ,Brent E. Wisse,John R. B. Lighton, Validation of an equation for energy expenditure that does not require the respiratory quotient PlosOne. 2019

In the above explanation, lower RER and RQ means better metabolism of fats, resulting in better weight management, more energy throughout the day, and less fatigue from lower lactate levels in the muscle.7Arnulfo Ramos-Jiménez, Rosa P. Hernández-Torres, Patricia V. Torres-Durán, Jaime Romero-Gonzalez, Dieter Mascher, Carlos Posadas-Romero, and Marco A. Juárez-Oropeza, The Respiratory Exchange Ratio is Associated with Fitness Indicators Both in Trained and Untrained Men: A Possible Application for People with Reduced Exercise Tolerance Clin Med Circ Respirat Pulm Med. 2008

Metabolism and Mental Health

Understanding the dynamics of metabolism can save your life more than you know. A lot of mental and physical illnesses arise from improper metabolism.

Diet and nutrition play a huge role in mental well-being. Taking into consideration a lot of factors, unhealthy food choices rank at the top of poor nutrition and metabolic functions.8Joseph Firth, James E Gangwisch, Alessandra Borsini, Robyn E Wootton, and Emeran A Mayer,Food and mood: how do diet and nutrition affect mental wellbeing? BMJ. 2020

Diet and nutrition play a huge role in mental well-being. Unhealthy food choices rank at the top of poor nutrition and metabolic functions.9Joseph Firth, James E Gangwisch, Alessandra Borsini, Robyn E Wootton, and Emeran A Mayer,Food and mood: how do diet and nutrition affect mental wellbeing? BMJ. 2020

Low metabolism also affects mental health starting from low mood, depression, stress, anxiety, and poor cognitive function.10Tina Ljungberg, Emma Bondza, and Connie Lethin, Evidence of the Importance of Dietary Habits Regarding Depressive Symptoms and Depression Int J Environ Res Public Health. 202011Laura Lachance, MD, Drew Ramsey, MD, Food, Mood, and Brain Health: Implications for the Modern Clinician Mo Med. 2015

Metabolic disorders like diabetes, Gaucher’s disease, and phenylketonuria result in mental health disorders (depression, schizophrenia, bipolar disorder) if not managed properly.12Giuliana S. Zuccoli, Verônica M. Saia-Cereda, Juliana M. Nascimento, and Daniel Martins-de-Souza, The Energy Metabolism Dysfunction in Psychiatric Disorders Postmortem Brains: Focus on Proteomic Evidence Front Neurosci. 2017

How Accurate Is Lumen

Lumen uses the same method as a laboratory setup, but on a smaller scale, to measure the respiratory exchange rate (RER). The device passed independent tests to validate its accuracy.  

Instead of a laborious, time-consuming setup of a metabolic cart and hours spent on encoding the data to a database, RER measurement is a breeze using Lumen. Yet, the results of the two tests are comparable.13Kent Lorenz, Shlomo Yeshurun, Validity of the Lumen ® hand-held metabolic device to measure fuel utilization in healthy young adults Research Gate. 2020

What Are The Main Benefits of Lumen

Here are some of the benefits you get from using Lumen Metabolism Tracker:

Personalized diet plan

The right kind of food for your particular metabolic process helps you to get the most out of your food.14Kent Lorenz, Shlomo Yeshurun, Validity of the Lumen ® hand-held metabolic device to measure fuel utilization in healthy young adults Research Gate. 202015J Galgani and E Ravussin, Energy metabolism, fuel selection and body weight regulation Int J Obes. 2010

You can better manage your weight, get the proper fuel that your cells need, and cause less distress to your digestive system.16Yiheng Chen, Marek Michalak, and Luis B. Agellon, Importance of Nutrients and Nutrient Metabolism on Human Health Yale J Biol Med. 2018

Every morning, you get a personalized diet plan to fuel you through the day, get a pre-workout snack to keep you fueled, and the number of macronutrients you need every day.

Lumen is convenient

You don’t need to go to the hospital to get tested for your RER. It also fits easily in your purse, so you can bring it anywhere with you, even if you’re attending a party.

Lumen is affordable

At first glance, it may not seem that affordable, but considering the time you need to book a checkup, the time spent for the actual checkup, and the lab fees, buying Lumen is a real win.

Lumen Metabolism Tracker

Lumen Metabolism Tracker

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How Is Lumen Different From Measuring Ketones

Lumen measures how your body metabolizes both fats and carbs by measuring the CO2 in your breath. Ketone urine sticks and ketone breath analyzers, on the other hand, determines if your body goes into ketosis after prolonged deprivation of carbs.

Ketone’s goal is to burn fats as the sole source of energy.17Michael A. Conlon* and Anthony R. Bird, The Impact of Diet and Lifestyle on Gut Microbiota and Human Health Nutrients. 2015

Lumen wants you to achieve metabolic flexibility.18Kiranjit K. Dhillon; Sonu Gupta., Biochemistry, Ketogenesis StatPearls Publishing; 202019Len Storlien , Nick D Oakes, David E Kelley, Metabolic flexibility Proc Nutr Soc. 2004

That way, you can limit your intake of certain foods without depriving yourself. You don’t have to worry about shifting from one food group to another since your body is more adaptive to what you eat.

Lumen reads if your body burns fat even if it hasn’t gone into ketosis. It measures carbohydrate usage, too, but ketone measuring devices do not.

What Are The Drawbacks

Because Lumen considers the food you ate from the previous meal or day, you may observe that your RER is high (signaling excess carbohydrate usage)

Lumen measures real-time your metabolic state so even if you ate a low-carb meal prior to taking a test, the results will still reflect the remaining glycogen in your liver and muscles from the previous meal. It is best to take the test two hours after eating.

Even if it measures carbohydrate use, it cannot replace a proper glucose test, though. If you have diabetes or showing symptoms, it is better to get an appropriate examination of glucose to know your blood glucose levels.

My Personal User Review

I really like the Lumen.

When I first heard about the Lumen I thought it was a great concept.

I love the idea of getting a real-time reading on your metabolic status, especially after a meal.  This is how you figure out how different foods and activities affect your body.

The first week you have to stay on top of consistently blowing 60-90 minutes after you eat and throughout the day which can be a chore to remember to do.   On the other hand, this reinforces to me that Lumen is doing the work to get your personalized metabolism accurately read by building your personal “breath signature”.

Some people think the app is glitchy but I didn’t get this impression.  In fact, I think the app is really impressive and intuitive.


After 1 week I’ve found some foods that put my body into a carb-burning mode and have made adjustments to get back into fat burning.

Now I’m waking up and achieving a score of 1 which is the most fat-burning score you can achieve.

How Much Does Lumen Cost?

Understanding how your body uses its fuel helps you get the right energy to feed it.

The goal of Lumen is for you to achieve metabolic flexibility to allow you to eat some food without upsetting your system.

Real-Time Metabolism Tracking

Product Name: Lumen

Product Description: The Lumen Metabolism Tracker is an easy-to-use, at-home metabolism tracker that helps you burn more fat by gauging how your diet and lifestyle affect your metabolism. The Lumen includes a "Pocket Nutritionist" smartphone app that keeps track of your readings and makes nutrition recommendations to help you optimize for more fat burning. Simply blow in the device after meals, sleep, and exercise and you're on your way!

Availability: InStock

  • Ease Of Use
  • Accuracy
  • Nutrition Planning
  • Battery Life
  • Durability


  • Easy To Use
  • Long-lasting Battery
  • Accurate, Real-Time Metabolism Reading
  • Personalized Nutrition Plan


  • Only takes carbohydrate intake into consideration
  • Does not delineate between different types of carbohydrates (ex: Fruit DOES NOT EQUAL Candy)
  • Not equivalent to a blood or ketone test


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Stay ahead with our newsletter: cutting-edge biohacking tips and the latest in nootropics, all in one place.
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Erik Abramowitz is a certified Nutritional Therapy Practitioner (NTP), Naturopathic Doctoral student, health coach, and father. He is the primary content creator for and the host of the Holistic Nootropics Podcast.

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