28 Days of Keto with the Wearable Challenge

In my ongoing effort to make the most of quarantine, I just wrapped up a 28-day experiment trying a keto diet. This diet had a twist though: if I stayed below a certain blood glucose level every day, I stood to make $700. Kind of.

Wearable Challenge

Freestyle Libre is a Continuous Glucose Monitor (CGM) which means its a sensor you wear to continually monitor your blood glucose levels.

The Freestyle Libre CGM sensor. It’s painless to apply and you barely notice it.

It’s intended for use by type I or type II diabetics, but this startup called Levels is repurposing it for non-diabetics to help them improve their diet and health.

And last but not least there’s the Wearable Challenge, a group that has partnered with Levels to help people adopt Levels to improve their health.

Here’s how the Wearable Challenge works:

  • You pay the Wearable Challenge team $850 after you’re accepted into the program.
  • They work with Levels to mail you two 14-day CGM sensors.
  • Every day for 28 days, you have to wear a sensor and scan it periodically with an app on your phone.
  • For every day that you stay below your max target blood sugar level (120 mg/dL) and meet certain other requirements (taking a picture of everything you eat, not having any gaps in your data) you get $25 back. If you do this every day for the entire challenge, you get a full $25/day * 28 days = $700 back. The remaining $150 pays for the sensor and you don’t get it back.

I’m not diabetic nor do I have a ton of weight to lose, but I’ve wanted to experiment with keto for some time and the Wearable Challenge seemed like an innovative way to go for it. I applied to the program, was accepted, and officially started the challenge on August 17th.


On a keto diet, you drastically reduce your carbs in your diet so your body switches over to using fat as its primary energy source.

I don’t enjoy cooking so headed to YouTube while preparing for keto to plan for what I’d eat throughout the challenge. I found this meal plan by Water Jug Fitness which I wound up following pretty closely throughout the challenge:

My meals look like this:

  • Breakfast: Omelette with two-eggs, mushrooms, spinach, and cheese with a side of cooked spinach, avocado, and two pieces of bacon.
  • Lunch: Taco salad with ground beef, onions, romaine lettuce, baby tomatoes, sour cream, avocado, and cheese.
  • Dinner: Some combination of a protein (fish, steak, chicken) with a side of vegetables.
  • Snacks:
    • Almond milk protein shake with MCT oil
    • Almonds
    • Pork rinds 😋

I usually meal prepped for lunch. I’d prepare 4 days worth of taco salad ingredients (by cooking the ground beef, cutting up the lettuce, etc) and placing them in a meal prep storage container which I’d put in the fridge and grab for lunch each day. This was really helpful because it made it super easy to stick to keto when normally I’d be drawn towards some less healthy meal for lunch.

Taco salad for lunch every day

While it may not work for everyone, I was mostly fine with having the same meals for breakfast and lunch every day with a little variety for dinner.

Scanning the sensor

The Freestyle Libre sensor can only hold 8 hours of blood sugar readings, which means that you have to scan it with your phone at least that often otherwise you’ll have gaps in the data (the Wearable Challenge team did make exception for gaps overnight though since depending on how long ou slept you might have some gaps in the data right after you headed to bed).

Every few hours I would load the Freestyle Libre app on my phone and hold it up to the sensor on my arm. It would scan the sensor and show me my blood sugar level along with a chart showing the trends that day:

For most of the challenge I stayed well below 100 mg/dL, but toward the end I started incorporating more carbs which had my numbers jumping to 110 mg/dL here and there.

The Freestyle Libre app is set up to pass data along to Levels, which also has an app:

It’s the Levels app that you use to take photos of what you’re eating, one of the requirements to get the $25 for that day.

The Wearable Challenge has access to the data in Levels so they can monitor how you’re doing to determine whether to pay you $25 for that day or not. Even though the Wearble Challenge is fairly new (I was part of the third cohort) I’m assuming most of the day to day management of it are automated at this point.

Keto Impact

The first week of switching to keto you go through something known as the keto flu which is a result of your body adapting to the new diet. I had many of the symptoms: dizziness, keto breath, sugar cravings, and headaches. After the first week though most of it diminished significantly.

One thing that really blew my mind was how little I thought about food after the first week. I suspect that’s part of keto in general, but also because I was eating the same meals almost every day. Food just got very… boring. Cravings and hunger almost completely disappeared.

I didn’t exercise at all during the first week, but after my body adapted to keto I picked it up again, doing 20-30m YouTube HIIT workouts a few times per week. I expected going into this that working out would be tough due to to low energy, but wound up not having any problems with it.

I actually had a lot of energy despite only consuming 40-50g of carbs per day. Your body really does adapt.

Most of the last ten years I’ve been around 185 pounds, varying a few pounds in either direction. At the start of the challenge I was on the low end at 183.2 pounds. After about 5 days, I was down to 179 pounds, and then slowly got down to 178 by the end, the lowest I’ve been since college.

What’s Next

In the end, I managed meet the requirements each day and will be getting the full $700 back:

But I’m not going to stay on keto. I enjoy too many non-keto foods and am healthy enough where it’s not a huge deal to have some excess sugar in my diet right now. That said, I hope to find some balance between my previous carb-heavy diet and keto.

And who knows, if quarantine goes on long enough, maybe I wind up going back on full keto and trying to get down another few pounds. We will see.


This little adventure wouldn’t have been possible without the Freestyle Libre, Levels, or the team organizing the Wearable Challenge. Huge thanks to everyone who helped make it happen. Also, shout out to my wife for putting up with my keto breath for most of the last month 🥰.

If the Wearable Challenge sounds intriguring to you, I’d encourage you to check out the website and consider applying.

One thought on “28 Days of Keto with the Wearable Challenge

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