Everything my doctor told me was basically right (or lessons from using Stelo for 3 months)

Let’s start this post by sharing an embarrassing fact: between leaving Disney in early 2022 and leaving Ohai in late 2024, I have gained about 28lbs (about 12kg). This wasn’t a new trajectory - going back to the beginning of 2021, I’ve put on 40ish pounds. By January 2024, I was a very unhealthy weight and just plain unfit.

My checkup with my doctor at the beginning of the year raised some alarms. I was at risk of being diagnosed as pre-diabetic. My blood pressure was starting to wobble higher from its normally consistent healthy level. I wanted none of this future and began making changes. My weight leveled off, but I was unable to really get it moving downward consistently, or improve my energy levels. Eventually, I started feeling crummy & unhappy¹ which led me to execute the reset I should’ve done back in 2022.

As part of the reset, I’ve incorporated using a continuous glucose monitor (CGM) to help track my blood sugar. CGMs are most often associated with diabetics who want to avoid the annoyance of finger pricks to monitor their blood sugar. These days, though, CGMs are also being used by athletes to optimize training and performance. These little coin-sized sensors provide insights more difficult to capture from other biosensors. There are also a few startups built around these non-diabetes uses, for example Levels.

I’m not a high performance athlete, but I still wanted a CGM. My initial goal was really simple: I was determined to lower my average glucose level and knock down my A1C before my follow-up exam this month (December 2024). I was also curious if it would help me gain insights into some occasional bouts of fatigue that didn’t seem tied directly to sleep quality.

Over the summer, a new CGM hit the market that didn’t require a prescription: Stelo. Stelo is made by Dexcom, makers of a popular CGM for diabetics, so they know how to build these sensors. The device costs between $84-$99/month, depending on the length of your subscription. They offer a single purchase (w/o subscription) and 1- and 3-month subscriptions. They can be expensed to your FSA/HSA if you want.

I started using Stelo in September. Attaching the sensor is painless. The “needle” part of the sensor is super thin. I’ve never felt it go in in the 6 times I’ve replaced the sensor. It’s more painful removing the sensor - the adhesive is basically like pulling a bandage off. The sensor uses bluetooth to share data to my phone, which then records it in the background, (optionally) sharing it with the Apple Health app. ² The sensor takes about 30 minutes to warm up/calibrate, and then you get readings every minute that get pushed to your phone periodically - usually within 5 minutes, but sometimes a bit longer. Each sensor will last 2 weeks, and the app will notify you when it’s time to replace it. It also manages a grace period so you have time to replace it when convenient.

The app has some rough edges and bugs, but works well enough. The app will trigger a notification when it detects a blood sugar spike (i.e. a significant change in levels, which can be the normal result of eating or a heavy workout). Tapping on the notification will offer you the option to log anything that happened around the spike - meals, exercise, a stressful event, or other notes. There are weekly insights, tips for managing blood sugar, and a few other things in the app, but I basically live on its home screen, which shows the most recent readings and a graph of the last 3, 6, 12, or 24 hours.

In the three months I’ve had it, I’ve basically learned that everything my doctor has been gently encouraging me to do really has measurable, direct effects on my blood sugar and, more importantly, how I feel.

I know what you’re thinking: I’m an idiot for not realizing this (or listening to my doctor). I’ll concede you have a point, but in my defense the sensor described the magnitude of the changes I needed to make, and the consistency with which I needed to implement them. Before, I fell into the trap of sort of making changes without doing anywhere near enough. The little real-time reminders, tied to real data about my specific body and choices I made that day - not just a timer that says “drink more water!” or whatever - created a perspective shift for me that registered deeper than anything else I had heard or tried to that point.

So, what have I learned since starting with the sensor?

First, the difference between sedentary and even a small amount of daily movement is significant. Even a short walk after a meal can curb a glucose spike that might trigger fatigue for me. A more intense workout, e.g. a 30-minute Peloton ride or strength workout, will lower my average blood glucose for the rest of the day. A consistent schedule of daily movement, even if it’s just leisurely walking, was the key to a sustained reduction in my average blood glucose.

None of this should be a surprise - it’s why Oura and Apple both have step counts or activity goals in their basic feature set. The nice thing is that I could see when my body needed the workout, which made it easier to stay motivated and make adjustments if my meeting schedule or family schedule prevented a workout or a healthy meal.

I was also able to see a correlation between food and the afternoon waves of fatigue that would hit on some days. There’s more I need to track there before I can share more conclusions, but there’s a pattern there that I’m now mapping to tracked macros for each meal. I’m removing carb-heavy quick options (e.g. grabbing a bagel) for busy days and incorporating more of the protein-rich salads I used to eat daily at ESPN’s cafeteria pre-pandemic. Those are just two examples of several significant tweaks I’ve basically measured my way into. These changes are more recent (in the last month), but they’ve been working out really well so far.

I’ve got a long road ahead of me, especially as I ramp back up into full-time hours over the coming weeks. I lost a ton of weight back in 2009-2010 - nearly 80lbs (36kg) over 18 months or so. I’ve done this before, and know it can be done without all of this technology attached. That weight loss journey was before kids and before I was a senior executive with a large team, though. ³ The demands on my time are greater and more varied these days. The tech helps me follow a plan I can sustain and adapt going forward, no matter where my career or family life goes.

In that way, the data has been a major catalyst for my health. The cumulative effect of the perspective shift, along with the smaller, weekly tweaks to sleep and diet, has been fairly dramatic: more consistent energy levels, better workouts, and my weight is finally dropping now. Oh, and my blood sugar labs and blood pressure were much better this most recent checkup, a big victory. It’s been worth it for me so far.

I may stop using the Stelo in the spring unless I get back into longer-distance cycling or running again, where the data could help shape the rides/runs. I do want to get back into both by next summer, if my body is up for it. If all goes to plan, I should be facing that decision in the spring. Wish me luck!

Tips & Tricks for Stelo

Here are some notes for things I’ve learned over the last few months. I’ll keep this updated as I learn more.

1. Shave your arm where you want to attach the sensor, especially if you have hairy arms. My first sensor was fine, but with my second one, the adhesive overpatch didn’t last the full two weeks. Since shaving my upper arm, I’ve had no issues. Few people will see that part of your arm, in case you’re worried about aesthetics.
2. I found using something like the Nood Eraser easier than a razor on that part of my arm.
3. Some folks also suggest prepping the area with SkinTac to help adhesion, but I haven’t needed it after shaving.
4. I do use the opposite product, TacAway to clean up the adhesive residue left behind by the sensor when I swap it out. Just wait for it to evaporate before inserting the new sensor.
5. Buy a pack of overpatches in case you do have one come off for some reason - an intense workout, tight clothes that peel up the edges, or whatever. Best to have them on hand for an emergency. You can find them at Amazon, of course, but your local pharmacy probably has them. When my second sensor’s overpatch came off, I was able to pick up compatible patches at my local CVS.
6. The nutritionist/lifestyle coach I’m working with warned me that CGMs can be somewhat inconsistent from one two week period to the next. They’re useful as directional guidance vs getting too worked about the specific level, at least between two different sensor periods. I have seen this in practice. If you need to be sure, you can pick up a blood prick sensor and see what the variation is. Those tend to be much more accurate, even amongst different manufacturers. I haven’t gone that far - for me the goal is the notification from Apple Health letting me know there’s a new baseline for my average blood glucose levels.

Note: The links to Amazon above are affiliate links, which may result in me getting some money if you click on them and buy.