Weight loss: Can a Lumen ‘metabolism reader’ help you lose weight more easily? How it works

Lumen metabolism measuring device and appLumen metabolism measuring device and app
Lumen metabolism measuring device and app | Lumen

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The Lumen device promises to help people to increase their metabolic rate, improve their fitness and strength, and lose weight. How does it work - and does it help you lose weight?

Lumen is the world’s first hand-held, portable device to accurately measure metabolism. It will provide a daily personalised nutrition and meal plan, as well as other insights and advice in to your sleep, workouts, and meal timing, via a connected app.

Put simply, your metabolism is a conversion process where the body turns the calories you ingest into energy. It is most often associated with a certain speed, and we’ll often hear people say they have a fast or high or slow or low metabolism.

A number of factors influence how low or high your metabolic rate is, including your age, height, weight and body composition.

How does the Lumen device work?

Lumen is a sleek tube-shaped breathalyser - and all you have to do is breathe in to it and the device does the rest.

It has been designed to improve your metabolic flexibility which is your body’s ability to swap between carbs and fats and use the correct energy source at the most effective time.

You are asked to breathe in to the tube several times a day so that you have a variety of samples for different times.

The device collects your breath, then sends the data to an app, which uses your breath measurement and a number of algorithms to then tell you if you are using fats or carbohydrates for energy.

The device works by detecting the levels of Carbon Dioxide (CO2) that you are breathing out. If you are breathing out a high level of CO2, it means you’re burning carbs but if it’s a low level then that means you’re burning fat instead.

This is identified using a five number spectrum. A number of 1 means you’re burning fats, 2 is mostly fats, 3 is a mixture of the two macronutrients, 4 is mostly carbs and 5 is carbs.

Lumen says that for optimal health, you want to be measuring 1 or 2 when you wake up as this means your body is good at burning carbs overnight while you’re sleeping and has begun burning your fat stores.

When measuring after meals, you ideally you want to see 4 or 5 as this shows that your body is using up the carbs you’ve just eaten.

After two weeks of use, the Lumen will give you a flex score of between 1 and 21 depending on how flexible your metabolism is, with 1 being the lowest. The higher the number the better, and your aim is to improve the number as the weeks pass and you follow the advice given.

The meal plan aims to improve this score.

Ultimately, the higher your score, the better your body has become at using the right energy source and the better your health will be.

What times of day should I use the Lumen?

You are advised to use the Lumen device first thing in the morning. Based on what your reading is, the app will then advise how much carbohydrate, protein and fat you should eat that day.

You are also asked to input how much exercise you will be doing during the day. So, it’s important to be honest about this as it will have an impact on the recommendations you are given!

As time goes on, the recommendations will also be influenced by the data you have given on previous days too.

It’s also a good idea to use the device again after you have eaten your meals as this will give you an insight in to how effectively your body is using the carbs you have just taken in.

Can the Lumen device help you to lose weight?

Yes, provided you pay attention to it - used correctly, the Lumen device could aid your weight loss goals.

As with most fitness aides, it’s a question of consistency and accountability. The device itself will encourage you to make food choices that allow your body to take its energy from those difficult-to-access fat stores, and will advise you to eat healthier meals with less carbs and less fat. However, there’s then the small issues of following through on the device’s recommendations - and that is down to you.

When you first get your device and download the app it asks you to choose your purpose for using the gadget so that it can determine your goals.

You can choose from metabolic health which is to improve your general health and metabolic flexibility, fitness performance which is based on nutrition to improve your work out and healthy weight loss.

How much does the Lumen device cost?

You can buy your Lumen as part of one of one of various packages that include access to the integrated app for different periods of time.

Right now, you can get all of these packages at the best possible priced as there is a sale on, meaning you can expect to pay £249 for the device and 6-months of tracking (use of the app), £299 with a 12-month track or £499 for an premium 12-month track.

If you sign up to the newsletter you can also get an additional £25 off.

Helpfully, Lumen also offers a money back guarantee. So if you’re not 100% satisfied after 30 days of use you can return your Lumen for a full refund, no questions asked, so you can give it a try risk free.

Once your paid-for months expire, the cost is £25 a month for use of the app, and you will need to keep paying for the app if you want to continue to use the device.

What else will help me get healthy?

There are numerous ways you can help improve your general health and fitness.

There’s exercise bikes, along with rowing machines, and lots of other at-home gym equipment.

You can also use protein powders to aid with your fitness goals too.


The promise: “Metabolic tracking in the palm of your hands - hack your metabolism.”

Our findings: if you’re someone who loves stats - say, you are a fan of your fitness tracker - this will likely be incredibly useful to you. It’s easy to use but requires a touch of dedication to do it regularly.

Over the course of a month, we found that following its advice with regards to eating carbs or protein helped to stabilise our mood, leaving us more consistently energised and less tired in the afternoon.

(We also lost a little weight, if that’s something you’re working towards).

One for the techie/fitness nerds - but it does work, if you work it.

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