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Continuous Glucose Monitors: Why & What

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This is a story and explanation about why I sometimes wear a glucose monitor. It’s visible on the rear of my upper arm, usually sparks a question or two, I’ve usually stumbled through a response, now I can simply pass this page along to anyone who asks.

Since maybe 2018, every now and again I’ll purchase a month-long ‘subscription’ to the Levels service, which is their app paired with a Continuous Blood Glucose Monitor.

It’s a tiny wearable device that uses adhesion to stick to your arm for two weeks. It has a 1cm thin bendable plastic needle that allows it to sample your blood glucose, continuously, store the data onboard, and then when you tap your phone’s NFC reader to it, your phone pulls the data off and… renders it.

A history #

A continuous blood glucose monitor is an improved tool on the finger-prick blood-draw glucose monitor technology that will be intimately familiar to anyone with type 1 or type 2 diabetes. I have neither kind of diabetes, but have used the finger prick monitors before.

Unsurprisingly, there’s some books I’d like to interject here, that amount to something like ‘an internally consistent perspective of human metabolism’. Books are just books, anyone can write anything in a book, so I’m not saying these books ought to count as anything like ‘evidence’ to you, simply that they were compelling for me.

Tripping Over The Truth is the most impactful book here, to me. It outlines a common feature among all cancers - that the cellular energy generation pathway in normal cells breaks and the mitochondria start to generate energy via fermenting environmentally available sugar (blood glucose). Virtually all cancer cells obtain energy via this alternative energy generation pathway.

There’s ahem several upstream/downstream implications.

These books all are coherent with each other around things like:

  • Sugar interacts with the body’s endocrine system, thus it has the same effects on the human body as hormones. You know how when children hit puberty, they change in ways unrelated to how much food they are or are not eating? Sugar has a close-enough effect at any chronic level.
  • half of the dry weight of your body is mitochondria
  • Mitochondria and one’s gut bacteria all sorta… matter. And can be healthy or unhealthy.

This layers on top of a change I made to my life in 2015 - I read the NerdFitness guide to Intermittent Fasting, and jived with it. I stopped eating breakfast, started doing the 16/8 ‘intermittent fasting’ plan; I stopped eating breakfast, and moved my breakfast omelette + veggies to my lunchtime meal. Everything else stayed the same.

I dropped so much hassle, food prep, cleaning time from my life, and got nothing but upsides. At the time my partner and I were traveling a lot, and there was substantial mental overhead to prepping meals in constantly novel houses, often while trying to do so quietly to avoid waking anyone up. I then could simply wake up, make my coffee, and be fully ready for the day.

I’ve been doing this for ten years, so it’s habit now. When I eat breakfast (very rarely, only when with others who want to eat breakfast) I always think “wow, I couldn’t imagine doing this every day.” and then usually skip lunch and eat again at dinner time.

I still binge eat sometimes. I’ve definitely got a partially disordered relationship with food, always did since childhood. I think many people use food to deal with emotional loneliness, and sometimes that is still a thing for me, but that falls outside this exact article.

I like the idea of semi-regularly doing a 24-36 hour fast, but only occasionally do maybe 22 hour fasts. Dinner one day, don’t eat again until about dinner the next day, these are never planned just sometimes happen. When I’m not eating carbs regularly, i very rarely experience the sensation of hunger.

What the data looks like #


That ‘mountain’ happened as I ate a carb-y dinner (and animal crackers) and then did late-night snacking of more pasta and ice cream at ~11pm.

my blood glucose goes from 80 to 175, across perhaps, and returns to baseline the next morning by 10 or 11a. You can almost see my body releasing insulin (to bring the glucose back down) then it climbing again as the food is absorbed. then released again, climbing, and eventually the entire metabolic load of the food finishes and it drops back down.

(remember, ideally I’d eat lower carbs, and not so late at night. My body would get to enjoy many more hours at the lowered blood glucose level)


The above level is what lowish-carb eating might look like on the first day, and here’s partial data on what it might look like after low carb for a few days. (Don’t be put off by the red, this is an app that is trying to keep diabetics from dying)


This is a normal blood sugar reading for a sustained low-carb day. You can see my blood sugar going up throughout the day. This is very normal, obviously the body can manage its glucose levels, can raise them or lower them as needed. It’s not as obvious what and when I am eating - I use the Levels app that ingests this raw data, to record what I eat, if I want.

I simply find it fascinating to see how my body does and does not respond to what I eat. I find it much easier to manage and stay ahead of my desire to binge, because I know I’ll be looking at the effect of it on my glucose for a while.

I really like the feeling of clean eating, and I use the continuous glucose monitor to refine some of my habits around my nutrition. Lots of the most interesting parts of this data, though, is the unfolding, self-observing nature of the data. I encourage you to try it, I imagine you’d find it interesting, with one or two novel, experiential insights that you wouldn’t otherwise encounter.

Why neither of us need the glucose monitor #

The devices are quite expensive. This is the ‘gold standard’ of medical care for type 1 diabetes medication, so most people pay for these via insurance. It’s $100 per two week sensor, or $50/week to get minute-by-minute monitoring of your glucose levels.

Certainly doable, but not cheap. Thus why I get these only so often. Mostly I manage my own nutrition via my own head, and will and will not binge regardless of the sensor.

The sensor helps me see how quickly and how much my body responds to the presence and absence of certain foods, and in an extremely real-time way, and I love it.

Strong Defaults Will Win #

Three key food defaults:

  1. My first meal of the day is not until after noon, and I usually stop eating by 8p, so I get daily ‘16 hour fasts’. I don’t count the time immediately after eating and while sleeping ‘fasting’, so really I just push my first meal of the day several hours to lunch time or the afternoon, at the ‘cost’ of occasionally being able to detect the physiological sensation of hunger, which passes always in just a few minutes.
  2. That meal, which is one of two I’ll eat that day, is usually: brocoli, mushroom, spinach, eggs, sardines, lots of olive oil, salt, pepper, maybe tumeric. It’s pure healthy fat, enough but not too much protein. No carbs.
  3. I usually eat whatever I want for dinner. Home cooked, or eating out. I love Indian food, all forms of Spanish & Latin American food, Thai, Vietnamese, the various forms of Chinese food, pizza, and more. Ice cream and cookies, bread, pasta. I generally avoid cookies and dessert type things, but sometimes, especially if it’s abundant in the environment, I partake. Sometimes I go no-carb dinners (shrimp, salmon, zucchini, squash, mushrooms, kimchi, brocoli, sauerkraut, hardboiled asian-style eggs, greek yogurt, spinach, olives, pickles, EVOO and coconut oil, almonds. So many options, this would be way too much food to eat all at once, but it shows I can cycle things through while eating abundantly)

I don’t drink anything that has sugar added. Most days the liquids I have are: Water, black coffee/espresso (if I/it needs cream, Almond milk or heavy cream), tea.

I’ve regularly done low-protein mostly vegetarian keto-compliant nutrition profiles before, and very happily. (basically, no carbs, 1/3rd consumed food is protein, 2/3rds fat. Protein comes from many places besides meat, but I’ll usually have a few shrimp, a piece of salmon, or anchovies, at least every other day)

Since my ‘default meal’ has been almost identical for a decade, and I’ve shaped it into a delicious and fully keto compliant meal, the difference between me being ‘fully keto’ and ‘not at all keto’ is just what I do with my dinner, and if I’m choosing to abstain from sugary, carb-y, food.

I used to be fully vegetarian, and for a time when my then-partner was trying to become pregnant, we both added small amounts of high-quality protein to our diets, while going out of our way to avoid endocrine disrupters and any sort of metallic bio-accumulation. I’ve retained the occasional consumption of salmon and shrimp, along with the regular consumption of sardines. I never eat chicken, beef, pork, deer, for reasons of ethics and health. I don’t drink milk (lactOSE, it’s sugar, and contains Animal Growth Hormone (an endocrine disruptor)) and don’t eat much cheese, ideally. If I do, it’ll be (at its best) a hard goat cheese, occasionally.

Who knows if this is working. I’m 35, and have as good of a body composition as I could have, and always have. I’ve been eating mostly this way since 2015.

Maybe I’ll stick a video up here of me making my ‘default meal’. It’s very easy to scale serving sizes up to feed as many as 6 people at once, or making four or five servings for myself (to store as future meals).

Many, many others have eaten this meal with me, and pretty much everyone says “surprisingly delicious, despite it’s unconventional composition & appearance”.

It’s a one-dish meal, of course, and there’s zero cleanup. I have a very refined set of preferences for how I like to use my kitchen

Effortless ease and excellence is all I want. I encourage you to read the books I mentioned above.

How I nudge myself into full-on ‘zero carbs’ when I want #

It looks pretty bonkers, the way I eat, when I’m doing something strange, if you were to be there looking over my shoulder the whole time.

But, I’ve nudged my eating profile in this direction for a long time, and I love it. If you were curious for easy places to start experimenting with the best of this way of being. This is how I sorta nudged myself in this direction, and how I outline this to others:

  1. Start maxing out olive oil and coconut oil consumption. It’s possible that coconut oil, swished around your mouth for a few minutes, is good for reducing the nutrients available to the bacteria that contribute to bad breath and cavities. So, once or twice a day, spoon a few grams of coconut oil straight into your mouth, swish it around for a bit, then eat it. Two nice things for the price of 1. Use regular olive oil for cooking, and atop every meal you eat, pour as much olive oil as you can until the amount gets ‘excessive’. Free, delicious, satiating fats. A few heavy drizzles is like 25 g of the good stuff.
  2. Add almonds, olives, and hard cheeses to your kitchen, and start starting snacking with those items. All are very portable, perfectly delicious, satiating. filling. Don’t even stop snacking on other stuff, just when you go for a snack, have at least some of the above. Maybe stop other kinds of snacks eventually.
  3. Add and practice and refine a meal of sauteed mushrooms, broccoli, 3 eggs, LOTS of extra virgin olive oil, and almonds. Get canned sardines and sometimes add them to that meal. Feed a friend or two with the meal, store some in a tupperware for later. This meal will do a lot of heavy lifting for you. Rotate in zucchini, cucumber, riced cauliflower, artichoke hearts. Anything cruciferous, go all in on. And olive oil.
  4. Don’t try to eliminate any food stuffs from your routine! Don’t think about stopping eating anything that you’re regularly eating. At best perhaps be less quick to replenish finished supplies of things like ice cream, crackers, frozen meals, processed stuff. If you’re drinking sugar, though, I think it’s worth cutting that immediately.
  5. See what it’s like to stop eating at 8p, rather than eating late into the night.
  6. Try a single ‘don’t eat anything besides coffee/tea or coconut oil until noon’ day.
  7. Combine the last 2 points. Stop eating at 8, don’t start until the next day at noon, x1. Evaluate. If you managed OK, do it for 2 days.
  8. at this point, you are good at that vegetarian-ish keto meal, and you’re intermittent fasting. If you slip that meal in as the first meal of the day, even if you don’t change anything else about your eating, you’ll now be managing to spend most of your life with very low blood glucose, and will experience small ‘fasting’ moments often-enough. huzzah.

If you wanna do the full keto thing, here’s how I do it, cobbled together from all the various internet sources, reddit, my own experience, proclivities, idiosyncrasies.

  1. vegetarian bullion cubes (have a cup of broth once or twice a day, or more. As much as you want, have the broth, it’s extremely nice.)
  2. Morons lite salt (supposedly electrolyte demands go up when not eating any carbs), add some to water with a Mio b-vitamine electrolyte supplement, mix this with your water
  3. almonds and olives and olive oil and coconut oil will be a perceivable fraction of your nutrition. I have like 100g, combined, of the above w/most meals
  4. Push your lunch meal to a bit later like 1 or 2p, sometimes. Or let it happen. Since I’m very pro-fasting, and low-hunger-queue, often enough I’ll find myself not eating for the day until quite late in the afternoon. I always feel an odd sense of accomplishment when this happens. Sorta patting my nutritional and digestive and metabolic systems on the head. pat pat nice work there, I see what you did. pat pat

I don’t have tips or strategies for eating meals out with others and not completely violating the above norms. So, usually I just eat whatever looks good to me, don’t sweat what happens temporarily to my blood glucose, and then resume my normal nutritional pattern at the next regularly occurring meal. If I eat out for lunch, I eat my big veggie omelette for dinner.

There have been times that I’ll eat TONS of sugary things and snack throughout the day, morning to night, btw. Usually it’s when working in offices that have a strong free snack game, but that happens in the context still of mostly intermittent fasting, that veggie omelette thing, and lots of fats. (Hard cheeses, almonds, olives, etc).

Soooooo experiment! see how things go.


Does the little thing in your arm hurt? #

No. Not when ‘installing it’, or after. I can sometimes detect a slight tug, if I turn or push in a certain way. I rock climb, even with all that movement I usually don’t feel a thing. Not while sleeping, or showering. I forget I’m wearing it, quickly enough.

You’re so strange. This seems odd. #

You don’t know the half of it.

But ✨my✨ body needs… #

Great, this is for me, not for you. I still think I’m right, and I can be obnoxious about it, but at least now I can just give you a web page instead of sputtering at you about books and “just because it’s dominant doesn’t mean it’s right” theories of human health. And colonialism, and white supremacy.

Misc Resources #