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Lumen Review: Can It Help Your Metabolism?


Lumen review - Dr. Axe

Sponsored Content

I’m a big believer in the power of tracking devices when it comes to improving my health, considering they’re capable of measuring important aspects related to my metabolism, such as my food intake, sleep and fitness patterns.

One device that’s been scientifically shown to measure metabolism markers with great accuracy is Lumen, a new type of breathalyzer that is simple to use everyday. This device can let you know if you’re burning fat or carbs for energy — which is a huge deal when it comes to lowering body fat, getting fit and reaching your ideal weight.

Lumen is unique because it focuses on improving metabolic health. Why is this important and why should you be tracking it?

Your metabolism governs so many bodily functions, including giving you physical and mental energy, playing a critical role in weight management and more.

In the Lumen review below, we’ll look more closely at how the Lumen metabolism tracker works, plus pros and cons of using it for goals such as fat loss.

What Is Lumen?

The Lumen metabolism tracker is a tool that’s used to measure and improve your metabolic health. It’s a unique hand-held, portable biotechnology device that you breathe into daily (a breathalyser).

Lumen refers to itself as “The world’s first metabolism plan.” The plan combines state-of-the-art metabolic tests with ongoing guidance from nutritionists and metabolic experts.

This device is able to use your breath as an indicator of your “metabolic fuel utilization,” or how much carbon dioxide is being exhaled and oxygen is being consumed. Lumen uses the “Respiratory Exchange Ratio” to analyze the CO2 in your breath in order to determine whether you’re burning fat or burning carbohydrates. It then sends you info regarding your metabolism by syncing with an app made for your smartphone.

When you first begin using Lumen, you complete a questionnaire focused on your eating, sleep and exercise habits. Questions include those about:

  • Your weekly workout routine, including the types of exercises you usually do and how many times per week.
  • Meal timing, including how long you typically fast overnight.
  • Types of foods you usually eat, especially how many carbohydrates.
  • General level of activity when you’re not exercising (for instance, how much sitting you do at work most days).
  • How much sleep you typically get.

Every Lumen user’s plan is unique and includes specific daily food recommendations, weekly metabolic assessments, live chats with nutrition experts and access to Lumen’s food library.

Does the Lumen really work? Testimonials, as well as several studies, suggest that it can help most users work towards teaching a healthy weight and maintaining an efficient metabolism.

The benefits and importance of having a healthy metabolism include: protection against developing obesity, diabetes, high cholesterol and high blood pressure, as well as other issues.

Achieving “metabolic flexibility” is one of the main goals of using Lumen’s program, which refers to the ability to burn both fat and carbs for energy, which can lead to easier weight loss.

How Lumen works

Features and Benefits

Does Lumen really help one lose weight? It certainly can, if you consistently track your diet, workouts and sleep patterns with it, and commit to following the program’s advice.

Some of Lumen’s main benefits include:

  • Helping you to figure out how you’re most likely to lose weight based on your current lifestyle.
  • Taking into account your starting weight, goal weight and lifestyle in order to give you guidance on how to best lose weight and at what speed.
  • Reporting back information in real time about how efficient your body is at burning fat and carbs.
  • Recommending what and when to eat based on your goals (such as how many grams of carbs you need for activities).

Here’s more about Lumen’s features and benefits that can support metabolic health:

1. Reveals How Well You’re Using Carbs vs. Fat For Energy

When you breathe into the device it reads the amount of CO2 being exhaled. High CO2 indicates higher carb burning, while lower CO2 indicates higher fat burning.

Lumen then reports back a number to you indicating the percentage of fat and carbs that you’re burning. In the morning, it’s ideal to burn more fat since you’ve been fasting overnight. Later in the day, it can be more beneficial to burn both carbs and fat that help to keep you metabolically flexible and fuel activity.

2. Focuses on Meal Timing and Intermittent Fasting

When you eat is as important as what you eat. That’s because meal timing impacts your internal body clock (your circadian rhythm), which keeps your metabolism working at its best.

Lumen claims that users who regularly practice intermittent fasting tend to lose up to two times more weight compared to those who don’t. The program recommends avoiding meals and snacks ideally within the 3–4 hours before going to sleep, and suggests fasting for 12+ hours daily if possible (overnight).​​

The goal is to keep your metabolism in great shape by using the power of fasting to promote strong mitochondria activity and insulin sensitivity — this way your body burns more carbs and fat each day.

3. Encourages Lower-Carb Consumption for Weight Loss

Cooking with fresh, healthy ingredients is considered a key component of metabolic health and weight loss, according to Lumen as well as most other health experts.

While a balanced diet is best for long-term health, if weight loss is one of your main goals, a lower-carb diet is suggested to help with burning fat, controlling your appetite and maintaining higher energy levels (due to less blood sugar fluctuations).

Some people using Lumen may choose to follow a very low-carb, very high-fat ketogenic diet, but this isn’t required or always necessary. The keto diet can boost fat loss, often quickly, but it’s not the only way to drop excess body fat.

To improve your body’s ability to burn fat, Lumen recommends avoiding refined carbs (like pasta and bread) and foregoing carbs with dinner.

Carbs are not discouraged altogether, since they support “metabolic flexibility” (such as by playing a role in thyroid health), but they’re encouraged earlier in the day rather than close to bedtime. Lumen’s customized nutrition program will suggest a specific carbohydrate limit for you to stick for the best results. It also uses your measurements to recommend meals that will either provide more fat or more carbs.

Depending on your general health and body type, you might also be advised to occasionally have “high-carb days” in which you increase your healthy carb consumption to replenish glycogen stores that your muscles use as fuel. This strategy can help prevent a dip in your metabolic rate, supporting long-term weight loss or maintenance.

4. Emphasizes Consistent Low to Moderate-Intensity Workouts

Exercising regularly is thought to be one powerful way to maintain a healthy metabolism and to stay within an ideal weight range. However, you don’t need to push yourself to extremes or exercise very intensely to see fitness improvements and results.

To support your metabolism and fat-burning abilities, Lumen focuses on moderate exercise, typically including a mix of strength-training and aerobic activities like brisk walking. Avoiding either too much or too little exercise is the best way to keep “stress hormones” such as cortisol within a normal range.

5. Strongly Suggests Focusing on Quality Sleep

Sleeping between 7 to 9 hours every night is a key recommendation for all adults. According to Lumen’s website, Lumen users who sleep 7–9 hours a night tend to lose more weight compared to those who sleep less.

The program advises users to stick to a regular sleep schedule in order to regulate their circadian rhythm.

Prior to bedtime, eating a light dinner and then fasting is encouraged, both of which can ease digestion. It’s also important to watch your caffeine intake after the morning to encourage restful sleep.


Some reviewers of Lumen have pointed out that compared to other fitness trackers, the Lumen device and program require a bit more of a consistent commitment in order to be effective.

That being said, once you get the hang of using Lumen, which you simply breathe into about 3x per day for less than one minute, it becomes pretty easy to stick with. After some time of using it, you can decrease how often you breathe into the device, down to about once per day in the morning. But if you want to use it more, you can continue to keep high quality measurements as Lumen gets to know you.

The results you’ll experience from Lumen are ultimately reliant on your own motivation. For the most health improvements, you’ll want to manually input information, breathe into it regularly and follow the program’s guidelines daily.

Other potential drawbacks of Lumen include its price (several plans and rates are available, but it’s usually over $100 to purchase) and that it looks very similar to a vaping device, which some people don’t like.

If you’re not interested in intermittent fasting or a lower-carb approach, then you may also not be happy with Lumen’s weight loss advice.

How to Use

The Lumen metabolism tracker requires you to breathe into the device daily, several times per day, which measures factors related to your metabolism, such as how well you burn carbs for energy. Personally, I use Lumen to find out if I am burning fat or carbs for energy.

You’re encouraged to breathe into Lumen before you eat your first meal, after you eat, before you exercise, after you exercise and last thing at night before going to sleep. Users can also do a custom check-in anytime during the day. You often need to breathe into it two times in a row to get an accurate reading.

For the most benefits related to a boost in your metabolism, weight loss and fitness improvements, Lumen encourages users to follow their customized plan and to “ lead an active, healthy lifestyle.”

The program will create and adjust your nutrition plan based on your body’s actual needs and CO2 levels, which means every person’s plan is different.

I’ve recommended Lumen to past patients and clients to support weight loss efforts, balance blood sugar and just knowing how different meals and foods affect their metabolism.

It takes about two weeks of continued use for the app to create your weekly summary (which includes a Lumen Flex Score, an indication of the flexibility of your metabolism) and to provide your personalized nutrition plan. The plan itself is very specific, including suggestions for meal timing and macronutrient intake.

Lumen levels

Cost and Where to Buy

If you’re new to using Lumen, visit their website first to learn more. You can also complete a survey to understand which plan may work for you. .

Once you complete your initial questionnaire, you’ll be offered a payment plan. The device itself and the accompanying program sell at various prices depending on how long you plan to use it. New users are often offered a discount that equates to about $49/month.

The Lumen device comes with a small travel case, charging dock and USB-C cable. The device’s battery is advertised to last for around 14 days. To use the online program you’ll need to download the smartphone app, which is where all of your data will be stored.

It also helps that the company offers a “30 day money back guarantee,” making Lumen risk-free during your first month’s use.

As a special promotion, Lumen is offering a $35 discount for the first 100 people who use the promo code DRAXE at https://www.lumen.me/shop.

This is a paid promotion. 

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