Lumen - let the conversation begin 😋

[atomicspacebunny]

No idea. I got my first blood sugar meter when I was a teenager, but I after keto got me below 100 every day, I threw it in the trash. I’ll not be buying a new one. I have a few decades of experience with hyperglycemia however, and this was as high as anything I had ever experienced in my life.

Oooh the mystery of mysteries, the big hyper-G:

I guess you would not want to try to gain weight being hyperglycemic? (…then you become insulin resistant?)

Then there is the nitrogen balance issue where synthesis and uptake of proteins is not working correctly and you are in a negative nitrogen balance? (i.e. muscle catabolism and lipolysis rather then lipogenesis)

That is why I eat eat higher carbohydrate foods 21 hours before I go to sleep again so I can go into ketosis when sleeping and oxidize fat.

Footnotes:

[1] Nitrogen Balance and Protein Metabolism: “…Species which primarily obtain energy from metabolising nitrogen-rich compounds use more nitrogen in their DNA than species which primarily break down carbohydrates for their energy? [citation needed]. …” …More

[2] Mode of DNA replication: Meselson-Stahl experiment

[3] The nitrogen cycle

[atomicspacebunny]

A book by one of the 200 Angels (Ozryel) from the book of Enoch…How interesting?

References:

[1] “…According to the Book of Enoch, Sariel, also called Saraqael (communicants of God) and Azrael (whom God helps), was one of the leaders of angels who lusted after the daughters of men. …In the book of 2 Enoch he is usually listed as the fourth angel with the name of Samuil or Sariel. …” …More

[EZB]

So I’m convinced this device is garbage for me right now. I just blew a 5. I’m on a carnivore diet with zero carbs. A 5 is impossible. This thing really needs to calibrate to be of any use. I am a bit upset to have wasted money on this. They didn’t describe that it would be a useless pile of dung if you won’t carb up or are diabetic.

[jennasaurus]

I just ordered one! I’m hoping it doesn’t take three years to get to me

I’m glad I’ve gotten an idea of what other people’s experiences were like so I can make an informed decision on how I approach the calibration. The main thing for me is that my ketones are usually low in the morning so I might fast the day before and then do the first measurement mid-day, then follow the carb up instructions to try and get the full range. Maybe the calibration process helps balance out some inaccuracy caused by the fact that the Lumen is only measuring CO2 out rather than O2 in and CO2 out. Either way, I’m interested to see how it goes!

[amwassil]

@EZB It seems you’re still thinking ‘5’ is measuring carbs when it obviously can not be doing so. Without carving up for the calibration your range of RER values in very tight, probably tighter than mine because I’m not eating zero carbs. One of the things I’m trying to determine with my comparison to BrAce is whether the Lumen mumbers in a small range are useful or not to determine anything about fat burn. It may turn out not to be useful. That will prompt me to request raw RER values rather than the current relative Lumen values.

[EZB]

We are on the same page. It showed that I was burning less fat than my “baseline.” But it still said I was burning mostly cards—which is crap. This product was not described as being useless when I backed it

[amwassil]

Ignore the descriptive blurbs above the numbers. They’re designed to encourage Joe and Jill SAD dieter they’re eating more or less carbs, but for us they’re meaningless. We know we’re burning fat. And in your case probably undetectable carb. In my case, I might have detectable carb burn since I’m eating non-zero amounts.

More importantly for us, is whether or not it’s useless, assuming it’s actually measuring changes within a very narrow range of RER values. Without displaying the actual calculated RER value, I think it’s not very useful. In your case, because you calibrated a very narrow range of min/max values it might be useless, especially considering T2D adding complexity to your situation.

However, instead of getting discouraged because you’re blowing numbers you don’t expect, I’d suggest trying to determine why you’re blowing different numbers at different times and circumstances. That might be useful. If it turns out that the Lumen values returned are totally random over the course of a couple of weeks, then I think it would be safe to conclude the device is useless.

In my case, I’m using my Ketonix to try to determine if there is any correlation between BrAce and Lumen numbers that might be useful. So I’m reserving judgement until I can conclude one way or the other.

BTW, I just blew another Lumen 1. I had my regular morning liter of keto coffee between 5:30-6:00am, worked a 5 hour shift from 7-12, did some shopping afterwards. Took the sample immediately when I got home (1:30pm). So have not eaten anything since 6am. Surprisingly, BrAce was relatively low 9.6 ppm. The final 2-3 hours were quite busy and I suspect I was burning mostly FA. So if I was generating significant acetoacetate, it was either being utilized directly along with the FA and/or converted to/from β-hydroxybutyrate and not a whole lot disintegrating into acetone and CO₂.

[amwassil]

BTW, I just blew another Lumen 1. I had my regular morning liter of keto coffee between 5:30-6:00am, worked a 5 hour shift from 7-12, did some shopping afterwards. Took the sample immediately when I got home (1:30pm). So have not eaten anything since 6am. Surprisingly, BrAce was relatively low 9.6 ppm. The final 2-3 hours were quite busy and I suspect I was burning mostly FA. So if I was generating significant acetoacetate, it was either being utilized directly along with the FA and/or converted to/from β-hydroxybutyrate and not a whole lot disintegrating into acetone and CO2.

Just tested about 1/2 an hour after finishing my main daily meal. BrAce 10.9. At 3:30pm Lumen 3, tested on the balcony; at 3:40pm Lumen 2, tested in my computer room.

[EZB]

Unfortunately, I found the pattern easily. I blow a 4 within 12 hours after weight lifting. I blow a 3 always otherwise. Perhaps if I fast a few days, I’ll blow a 2. That isn’t really of any use to me. The raw numbers would give me better information maybe.

[EZB]

Blew a 2 this morning. Waited 5 minutes and then blew a 4

[amwassil]

[amwassil]

Two Lumen 1s in a row.

I started a fast yesterday at approx 11am. Blew a couple 2s and 3s on the Lumen during the rest of the day. BrAce was between 9 - 16 for all samples. Blew a couple of 3s this morning at 5 and 9am. BrAce was 10.5 ppm and 10.3 ppm respectively, surprising stable for 4 hours! At 9:30 I broke the fast (so about 20 hours or so) with my daily keto coffee. Blew two 1s in a row afterwards: at 1 and 2:45 pm. Again BrAce was remarkably close at 12.4 ppm and 12.5 ppm.

I just finished my main meal of the day and will test again in a couple hours.

[amwassil]

Check out this:

Mike's Excellent Glucose Monitor Adventure

2020/03/03 16:30PST Update [36%20PM] I changed the ‘target’ limits to 3.5 x 6.5 mmol/L. Meals: 11:00 - 12:00 Keto coffee 13:00 - 14:00 Main meal BrAce: 16.5 ppm Lumen: 5 (my first 5!) Interesting. I’m in ketosis, have a 5.6 mmol/L glucose, heading for 5.4. And I blow a 5 on the Lumen! I wonder if the Lumen is better correlated with glucose rather than ketones? Hmmmmmm.

[amwassil]

Well, after measuring glucose for nearly two weeks now - the sensor self-destructs in 2 days! - I am coming around to the possibility that the Lumen is actually working as designed. Despite my 3+ years in ketosis, my glucose is consistently withing the mid-low ‘normal’ range. That glucose is not disappearing by magic and it’s not getting stored as fat. Therefore, it must be getting burned - presumably by the various cells/organs that can not burn ketones and/or fatty acids. I think the Lumen is detecting it.

My hypothesis that my Lumen ‘range’ is likely something like .71 - .76 RER is starting to make sense, if in fact the Lumen is detecting that minimal glucose burn and reporting it as ‘carbs’. Yes, it would be immensely more useful if the Lumen indicated actual RER rather than an arbitrary range of only 5 possible values. Still, instead of comparing it to BrAce, I intend to compare it to glucose the next time I buy a sensor. I think that will be interesting, indeed. Stay tuned.

[Karim_Wassef]

just catching up here.Is there any way to use the Lumen to calculate RMR?

[amwassil]

At the moment, no.

[Jon2020]

Hi Everyone,

I’ve just signed up to this forum after coming across this post. I haven’t even had chance to explore the rest of the site yet but I felt I needed to reply because I might be of some assistance. A little background regarding me, I started my Keto journey a couple of years back and did really well, was super happy with results and the benefits the lifestyle brings, I fell off the wagon a fair bit for about a year but now I’m back to it and have been for 3-4 months (I’m by no means an expert and I’ve learnt so much reading just this one post). I’m a tech guy and just like @amwassil I’ve been on the hunt for some piece of technology that could help me monitor my progress doing Keto, I came across Lumen late last year and I placed an order straight away in the hope it would do what I wanted and if not it would be a new piece of tech to play with.

My Lumen arrived on Friday and after going through the initial setup and the suggestion to carb up for calibration day, I soon realised this might not work how I wanted it to. This is how I came across this post, I started google to see if anyone had managed to work the Lumen in a Keto positive way.

I think @amwassil is right, it would appear that the calibration day is setting the high and low values for you personally and the 1-5 score are just divisions between the two. This might be something that is useful for Keto but I think it leaves it open to way too much interpretation. I agree that raw values would be much more useful. This is where I might be able to help.

I’m a software developer here in the UK and I mainly deal with iOS apps and technologies, so the moment I figured out the 1-5 scale isn’t going to be that great I started work on picking apart how the Lumen works. I’ve only spent a few hours today on it but this is what I’ve achieved so far. I have written my own iOS app and I can successfully connect to the Lumen. I can see it has 2 bluetooth characteristics, one appears to have no use (or I am yet to discover it) the 2nd allows me to read and write, I have figure that sending 2 particular commands makes the device respond. One command gives me a static set of data (I’m initially expecting this to be something reporting the device battery level) the 2nd command starts the device streaming live data which changes and responds when I blow in to the device.

I’m some way off being able to figure out if there is a RMR number in the data somewhere, at this stage I’m looking at raw bytes and it’s fairly meaningless until I can start to spot some trends.

I will continue to play around with this but I wanted to know if people might find this useful and maybe anyone with more knowledge of the type of data this device is likely to report might be able to add some insight of what to look for.

[amwassil]

@Jon2020 Welcome aboard the forums, Jonathan! Please keep at it and keep the rest of us informed of your progress. I have an iOS device (iPod Touch) that I use with my Lumen. I for one would definitely like to get real numbers out of the device if it’s possible to do so. I suspect it is, but…

@Karim_Wassef FYI

[Karim_Wassef]

I agree. This has some great potential. The most direct is by using a real calibration for the device using real RMR data.

For example, I fast for 3 days and go get a real test for RMR at my local DEXA site. I capture the raw measured device results immediately before and after.

The. I eat my 5000 calorie keto bulk meals for 3 days with intense lifting and repeat the test.

Based on my past experience, those two behaviors will land me at 1500 and 4000 which are real min and max. If I can tie the device raw results to these real measurements, then the software can accept my data inputs for calibration and actually be usable.

This calibration might need to be repeated every three months for confidence or we could take more data points during the period (since the model may not be linear) but the ability to capture instantaneous RMR would be real.

My experience is that metabolism fluctuates wildly with many parameters- diet, activity, sleep, stress, temperature … and this would be the tool to help align the massive daily variation to real life control variables.

I could finally determine how my sauna and my ice baths are really impacting my metabolism!

Also - fellow engineer and scientist here. Let me know if you need some help or a guinea pig!

[RightNOW]

You might consider contacting the company. I think their likelihood of getting more sales, and having much more use of their product by people who are keto, lowcarb, or even diabetic but more interested in real data not ‘interpreted’ data, could be great if there was a decent app that successfully did what you are doing. Maybe you can get them to help you with info, or even funding who knows? If you present it well. I’d find the marketing manager of the corp and see if you can contact them directly.