A Rocket Scientist Homeschooler’s Insider Blood Glucose Monitoring Secrets, The Best Way To Use A Continuous Glucose Monitor (CGM), Blood Sugar Biohacking Tips & Much More!

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As I've mentioned many times before on podcasts, I've been using something called a “continuous glucose monitor” (CGM) at various intervals throughout my life for about 4 years or so.

Considering that, as I write about here, I regard glycemic variability (which is exactly what these CGMs track) and inflammation (which is a bit more difficult to measure as it typically requires a visit to a lab) to be my top two key biomarkers for health and longevity, my use of a CGM has given me some very valuable data on how my body responds to certain foods, supplements, exercises, lifestyle practices, and even emotions.

But how does a CGM work, exactly? 

What does the really tiny “filamentous” needle actually measure?

How do you get yours to “stick” for long periods of time, or in water? 

How does the phone gather data from the sensor, and is EMF a concern?

Does the sensor have to be calibrated to a blood glucose reading due to the fact it is recording interstitial fluid vs. blood? 

Is this type of thing, from an insurance standpoint, that is only available to diabetics? 

What do you do about activities that cause high glucose excursions, such as exercise/sauna/coffee, etc., which wind up decreasing the metabolic score when, long-term, those are all glucose stabilizing/insulin-sensitizing activities?

Are there certain supplements or herbs that do the best job controlling blood glucose?

I explore these questions and many others in this podcast with Josh Clemente. Josh is a rocket scientist who worked at SpaceX for 6 years, managing the team that designed the life support systems in their space shuttles. Over time, he started to notice extreme levels of fatigue and experienced volatile spikes and crashes of energy throughout his day. For someone who worked out consistently and followed the guidelines for what he believed to be healthy practices, it didn’t seem to add up.

After experimenting with glucose monitoring, he realized that he was pre-diabetic (borderline full-blown diabetic) and that the foods he was eating were having a significant impact on his performance. It was this discovery and struggle to derive actionable insights from his glucose monitoring that led him to start Levels.

Today, at Levels Health, Josh and his team are revolutionizing the way people think about their metabolic health. And why is metabolic health so important? Before Levels, an average person had no way of understanding how efficiently or inefficiently their body was producing energy. Levels enables you, using a new CGM system, to access and understand this information in real-time—so you can start making better diet and lifestyle choices to avoid those energy peaks and valleys.

During this discussion, you'll discover:

-How Josh became a rocket scientist…8:50

  • Josh was homeschooled and experimented a lot with engines as a child
  • Studied mechanical engineering in school
  • Became enamored with Tesla's electric cars
  • This led to a career with SpaceX

-How Josh became interested in blood glucose management…32:05

-How a CGM works, what it measures, and how it compares to a blood glucose stick…19:33

  • CGM measures glucose molecules via a patch attached to the skin
  • Filament in the skin interacts with sugar molecules in interstitial fluid
  • Interstitial fluid reading in a CGM may vary slightly from a blood glucose monitor reading
  • Calibration estimates where the blood levels are compared to the interstitial fluid
  • Important for people with diabetes who need to monitor blood glucose quickly
  • Interstitial fluid monitoring is preferable from a general wellness point of view

-How the Levels app calibrates with the CGMs on the market…24:00

-Gold standard location for placement of the GCM on the body…30:45

  • Libre was tested in the upper arm
  • G6 tested in the ab location
  • Upper arm is the more comfortable location

-How to keep the CGM on your body for long periods of time…31:00

-How to obtain a CGM without faking you have diabetes…37:50

  • All devices currently available are prescription only
  • Levels platform includes physician consult and prescription
  • Insurance doesn't recognize a CGM as a legit use without diabetes
  • Approximate out of pocket cost – $399 first month, $199 thereafter

-Whether it's necessary to wear a CGM in perpetuity…39:15

  • It's up to the individual and their own goals or need for accountability
  • “What gets measured gets managed”
  • Feedback on one's lifestyle greatly influences our decisions
  • Oura Ring

-What a “metabolic score” is…45:15

-What an “activity response” is…56:15

  • All activities have metabolic implications
  • Assumptions made on whether a meal is good or bad for you
  • A meal with or without a post-prandial walk affects the activity response
  • “Compromise” when variables such as sleep are lacking

-How to keep blood glucose stable throughout the day and beyond…1:01:00

-Glucose disposal agents that may be outside the norm…1:06:45

-Josh's personal practices to stabilize his glucose levels…1:11:45

-And much more!

Click here for the full written transcript of this podcast episode.

Resources from this episode:

– Josh Clemente:

– Podcasts and articles:

– Books:

– Gear and supplements:

– Other resources:

Episode sponsors:

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Do you have questions, thoughts, or feedback for Josh Clemente or me? Leave your comments below and one of us will reply!

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15 thoughts on “A Rocket Scientist Homeschooler’s Insider Blood Glucose Monitoring Secrets, The Best Way To Use A Continuous Glucose Monitor (CGM), Blood Sugar Biohacking Tips & Much More!

  1. Josh says:

    What about EMF from these GCM Ben?

  2. Shelia Dence says:

    Dear Ben,
    Hello! I hope you have time to read my letter and send info or forward it to someone who might be able to give me direction.
    My name is Shelia Dence and I am a 4th and 5th grade teacher for Academically Gifted students. I was listening to your podcast with Josh Clemente. I am very interested in blood glucose monitoring for me and hubby but it is not in the budget right now – loved it and I am super interested.
    I have a student that is very interested in space, math, physics, etc. He can be a challenge because his maturity level is around 3rd grade (He is in 5th) but academically he is probably middle to high school. I can’t keep up with his math! Mom and Dad do a great job at home. They can’t homeschool him – I think financially and the fact that he drives them a bit nuts.
    What is the best way to go about having him advance on his own? I want to offer them the best suggestions. We are a public school in NC. I feel he can write his own story and advance to work at NASA or whatever he wishes. I think you and Josh could be the answer to my questions. Do you know of programs he could do at home and get credit…. I am not even sure what I am asking…

    On another note, I am a believer and I loved your Sunday Edition. I also bought your book and it is my coffee table book. I have a Masters in Health Ed that I was never able to use – so it is my hobby now. Everyone wants to hire a nurse. I didn’t want to do school health but community or public. I couldn’t quit work to go to school for nursing so I kind of got a degree that I can’t use. I love your podcasts and your book.
    Thank you for all you do. I wish I could try EVERYTHING you recommend.
    Shelia Dence

  3. John Groberg says:

    I’ve used Nutrisense for 2 cycles of 2 weeks each. They use the Libre CGM and have their own app and support with nutritionists who will answer your questions and give you feedback on your data. I found it very useful, but keeping a CGM on all the time is both expensive and a bit of a pain to deal with always having to be careful not to accidentally have the sensor get pulled off during exercise, showering, sleeping, etc.. Once they come off, they can’t be put back on and you just burned $200.

    I know each individual’s response is unique, but I think there are probably a lot of best practices that can be learned from crowdsourced CGM data that will be 90%+ applicable to most others. I have been collecting a list of best practices for healthy blood glucose management- both from my own CGM trials and from others that have shared. Thanks Ben and Josh for sharing a few of your best practices. I’ll add those to my list. I’ve found the biggest glucose disposal response I’ve seen is with alternatiing cold water/hot water immersion. There is usually an initial spike followed by a huge drop that lasts for several hours and can “compensate” for some guilty pleasure carbs. I got this same response in at least 8 different trials during my 4 weeks of having a CGM. If stability is the goal, this is not the practice for you, but for massive glucose disposal, nothing I’ve found so far beats it, not even close.

    Is anyone aware of any online forums or blogs where non-diabetic CGM users interested in wellness, can share/chronicle best practices for glucose management?

    1. Jeff says:

      You mentioned you were “collecting a list of best practices for healthy blood glucose management- both from my own CGM trials and from others that have shared”. Would you be willing to share that? Also, if you had found some additional links and other insights relative to you testing – I’d be incredibly interested to follow up on those. I’m going to end up using agelessrx.com program ($90 for 14 days) and want to maximize my testing during that time.

      Kudos to levels on the incorporation of supporting data. I think that will be especially interesting and valuable… hopefully they get their program up and generally available shortly.

  4. Marieta Ruseva says:

    I enjoyed listening to this podcast. I am healthy and use the FreeStyle Libre. I do time restricted eating and noticed that my fasting glucose is within the “normal” range but at the upper limit. It spikes when I wake up. I also looked at my MTNR1B gene and found that I am homozygous for four SNPs associate with increased risk of high fasting glucose that explained my glucose results. Any advice apart to stay away from high fat diet? Paleo diet works well for me.

  5. MarkB says:

    Placement pro-tip for lean individuals;

    I have played with different locations for years and found that the area between my shoulder and tricep works best as there is a small “valley” of adipose tissue that the filament can sit in.

    Not affiliated with this youtuber but he nailed the location:


    Another issue one may experience with the back of the tricep is it may cause “compression lows” if you sleep on your back. This means that pressure placed on the sensor will cause glucose molecules to disperse from the area and the sensor will send a false “LOW” reading to the app. The abdominal or tricep/shoulder region tends to work better if you sleep on your back.

  6. Sil says:

    Ben, I love your content, and I admire how you consistently produce high quality content. Having that said, it would also be great customize the change the frequency through which subscribers receive their newsletter. For example, I would prefer receiving the weekly round-up and not the daily emails.

    It would help, and I believe others, to having less distractions, more focus and less fomo.


    p.s. this podcast convinced me to get a CGM. In other words, your content inspires me.

  7. Carmen says:

    Hey! I‘ve purchased the FreStyle Libre 2.0 –

    but would you recommend measuring mg/dl or mail/L (not having diabetes).?

    You can’t change these settings…


    1. MarkB says:

      The settings depends where you live/purchase the CGM. Assuming you meant mmol/L, which is the measurement commonly used in the UK, Canada, Australia, etc. Mg/dL gives the concentration by the ratio of weight to volume, in this case milligrams per decilitre and is used in the US. The easy way (not exact, but close) to convert is to multiply or divide by 18 (e.g. 5mmol/L x18 = 90mg/dL and vice versa).

  8. Howie says:

    Coffee consumption in healthy adults lowers postprandial hyperglycemia; In a fasted state it should have little effect or even lower BG. https://pubmed.ncbi.nlm.nih.gov/26337017/

    The reason: polyphenols.
    However, be sure to drink freshly LIGHT roasted coffee from high-quality coffee beans. Be sure to grind the beans right before drinking. In this way, the oils are fresh and not oxidized. The stuff that’s sold in grocery stores is straight-up poison. If you’re drinking dark roasted, old, or otherwise dead coffee then expect a BG rise.

  9. Signed up in October of last year. When will this even be available to us?

    1. Marissa Farrell says:

      thats very interesting.
      Makes me hesitate to sign up at that price!

  10. Len says:

    Great podcast, thank you both! Question on FSA eligibility if I subscribe and pay cash. Can it be reimbursed by FSA pre-tax plan I have through my work benefits?

  11. A CGM has been a game changer for me, and I am not prediabetic or diabetic. I use it in my Unconventional Cancer Protocols to monitor my metabolic flexibility. I wrote a Blog about my experience here: https://drdanenberg.com/cgm-my-cancer-journey/

    1. Kevin Amatt says:

      Do they connect to an app on a mobile? I have a Freestyle Libre monitor, but it only lasts 2 weeks.

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