...craving the sweet embrace of the sugary aid-station carbs!
I don't think that it is a controversial statement to say that as we age out of our prime years and into our more "senior" years, our bodies become less resilient and more prone to infirmities. Joints start to hurt more, backs ache, eyesight worsens, metabolism slows down, and our ability to heal becomes less effective. More simply, we become less efficient as biological machines. Years of abuse and less-than-ideal habits have a way of catching up with us (especially for those of that truly "abuse" our bodies running ultramarathons or thru-hiking). In addition to the slow and insidious degradation of our bodies at the mercy of father time, there are also the genetic ailments that we cannot escape from (although with modern advances in genetic engineering, that may change one day).
As for myself, now within reach of my 50s, I certainly have my share of genetic predispositions that I'll need to forever be aware of. Despite three of my grandparents living into their late 80s, I do have some familial history of ailments such as stroke, dementia, and Parkinson's. Additionally, cancer hasn't entirely ignored my family either. The biggest genetic factor that I have been most acutely aware of however, and the one I've been most vigilant about tracking, is my blood cholesterol. My family is rife with high cholesterol (and triglycerides)...so much so that it has led to severe clinical atherosclerosis in many members of my immediate and extended family (heart attacks, bypasses, stents, major arterial blockage...etc). It's because of this that I regularly track my numbers. Even back in my late 20's I saw that my cholesterol levels were "borderline". In those younger years, my doctors were mostly unconcerned with my numbers, citing an overall low "risk score". But as I've aged, my cholesterol has taken a more front-and-center position with regard to my health.
Over the years, my total cholesterol numbers have hovered around the 200 mg/dL recommended upper limit (with it often creeping over slightly). More importantly though, my LDL (or bad cholesterol) has always been high (always over 100 mg/dL). This is the cholesterol that the majority of published research shows leads to problems such as heart disease and atherosclerosis. Over the years I tried experimenting with my exercise and diet to improve on that number. Ever the scientist, I would change one variable at a time, keep at it for a while, and then have my numbers checked again. No matter what I did though, my numbers never improved. Exercise volume didn't matter, over-the-counter supplementation of various fish oils or omegas didn't matter, heck, even going entirely vegan didn't help. The ultimate diagnosis was that I had a mild form of Familial Hypercholesterolemia. In other words, I inherited a trait that leads to higher-than-normal levels of "bad" LDL cholesterol in my blood (and starting at a younger age than is typical).
For anyone that knows me, it might be weird to think about this. I consider myself to lead a pretty darn healthy lifestyle. I typically run 40-50 miles per week, incorporate some strength training and yoga, eat mostly well (we'll come back to this), don't drink alcohol, and am fairly fit overall (a BMI in the low 20s). It is weird to think that despite all of this, it is very possible that I could be walking around right now with significant arterial blockage due to high cholesterol and early-onset heart disease.
The good news here is that a recent cardiac calcium exam came back normal, and that for now, I do have healthy arteries. I also had my lipoprotein(a) value checked, which is another direct measure of genetic predisposition to heart disease...and it too was normal. With all of this said though, I did finally reach a point where I had to accept that changing my habits was not going to keep my cholesterol numbers safe, and that it was time to start thinking about prescription medications.
I have always prided myself on the fact that I didn't have to take any regular medications. Any time a medical form would ask me, "what medications do you take?", I would smugly respond, "N/A" or "none". But the time came, where I finally had to admit medications were in order. About one year ago, I started taking the smallest possible dose of a blood statin (5 mg), and my cholesterol (and triglyceride) numbers finally moved in the right direction (and moved a lot!). Every three months when I check, my total cholesterol now floats around 160 mg/dL, with my LDL and HDL both sitting around 70 mg/dL. I loathe the fact that I now take a regular medication, but the peace of mind it brings me is well worth it. I was also worried about potential side effects (especially myalgia), but thankfully, I have not been sensitive to this medication at all, and have not experienced any side effects that I know of.
So where is this post all going then, and what's with the "glucose" title?
For the past year as I've been regularly taking my tiny 5 mg statin medication daily, I have slowly lulled myself into something of a sense of biological disregard and complacency--almost a feeling of anti-vigilance with the notion that "everything is fine now, and I have nothing to worry about." But as we all know, father time continues to insidiously gnaw away at our seemingly healthy bodies, attacking us on multiple fronts.
I recently signed up for a free health screening at my work targeted for individuals over the age of 45. I somewhat smugly signed up knowing that again I would "ace" my blood numbers, and that everything else would be "in the green" as well. As expected, all of my test came back normal: cholesterol was excellent as were my weight and blood pressure. I was even tested for a specific antigen that can target very early-onset prostate issues...and it too was normal. A bone density exam came back with a reading of "bones of a 30-year old!" - woohoo.
What I didn't expect, was being told that I was officially "pre-diabetic".
WHAT!? How could I possibly be pre-diabetic (and what even is that!?). I am a healthy, fit, athletic person that is at an ideal weight. Diabetes is usually associated with being overweight, unhealthy, and eating really poorly!!!
What I came to learn, more specifically, was that my blood glucose fasting numbers were entirely normal (around 80 mg/dL). Going back through all of my past blood tests, this number has always been between 70 and 90 mg/dL...which is considered healthy. So why then was I being flagged as "pre-diabetic?" The answer is because of a different test that I was unfamiliar with: The A1C test. An A1C test measures the average blood glucose in a person over a roughly 3-month period and is reported as a percent. A normal A1C reading should be below 5.7%. My number came back exactly 5.7%. While this number is right at the absolute lowest limit of being in this "pre-diabetic" range between 5.7 and 6.5%, it is still in that range, and why I was flagged.
How come I had never heard about this before?
When I again went back through my past lab results it quickly became clear why I didn't know about this...because I had never had this number checked before. Given my age and my normal fasting blood glucose numbers, my doctors never thought it necessary to measure my A1C...meaning it may have been in the pre-diabetic range for some time and I simply didn't know. For hours after reading these results I kept asking myself, "WTAF!? How could I possibly be pre-diabetic?! I run 50 miles a week and eat healthy!"
But you see, it's that second part of that last sentence that turns out to be the culprit. While I don't imbibe in alcohol or gorge myself on fast food, pastries, or sugary sodas...I have come to learn that I have always had a sweet tooth and really enjoy my sugars....particularly the starchy and/or refined sugars. For example, some might reach for a handful of nuts or beef jerky for a quick snack. I will most often reach for the bag of pretzels, or the big plain bagel. Another example: Many might start their day with a couple of eggs. I start nearly every morning with a bowl of cereal. And while that bowl might be something "healthy" like plain cheerios or even oats, that cereal is always high in carbs. The other habit I've noticed is that I would often eat that bowl of cereal, and then sit at my desk to work. So, in short, I was eating a load of carbs, and then not moving. Similarly, I would often eat my dinners late, usually with a lot things like pasta, potatoes, or other starchy carbs. I think you probably see the pattern already starting to develop here and it's quite simple. I like carbs. A lot. Especially breads. Sure, as an avid runner, I need a lot of carbs. My muscles need those sweet sweet sugars to be able to move better, but my problem is that I most often ingest too many carbs in any one sitting, and typically on an empty stomach (meaning they'd absorb really quickly).
But all of these thoughts were hypotheses, guesses, and/or conjectures. I wanted to "see" what my blood was doing and specifically what habits of mine (both physically and nutritionally) were causing my blood glucose to be higher than it should be for my age and lifestyle. At first I experimented with a blood glucose meter. I would literally prick my finger before and after meals to record my blood sugar. But this quickly became bothersome and it was only giving me periodic data points (I will say that I do now have a newfound admiration for diabetics that must do this countless times a day. My fingers hurt constantly after just a week). I wanted regularly timed data to monitor and correlate with my activities and food intake. This is when I discovered CGMs - Continuous Glucose Monitors (not to be confused with GCMs or Global Circulation/Climate Models - an acronym I use a lot as a glaciologist and climate scientist). If you don't know what a CGM is, you have likely already seen them and didn't even know it. For years CGMs have been available to diabetics to wear as a way to monitor their glucose levels continuously (often in conjunction with an insulin pump). These devices are small, and typically worn on the back of the upper arm...and present as just a small "pod" stuck to the arm. The way they work is simple. When applied, the device uses a minuscule needle to insert a small sensor into the interstitial fluid around the fat cells of the arm. This sensor then measures glucose in that fluid at a regular (usually 5-minute) interval...sending the data back to a smart-device over bluetooth. The downside to such a sensor is that it is not measuring the blood directly, meaning that the values it reports are delayed about 15-minutes behind the true blood values (it takes a while for glucose to diffuse out to the interstitial fluid). This means if you want to get a "live" blood glucose measurement, you'd still need to measure blood directly from a finger prick, but, if you're someone like me, and you are mostly just interested in trends of how the body reacts to certain activities and meal choices, a CGM is an excellent scientific tool for this purpose. In March of last year (2024), CGMs became available over-the-counter and without a prescription for anyone to purchase and use...
So I bought one...and started wearing it.
Here's what I discovered...
First of all, the data are fascinating. There is something truly captivating and remarkable about watching your own biological processes unfolding before your very own eyes. It is almost like you get a secret window to peer inside your own body and catch a glimpse of the biological machine's inner workings. Every time I would eat anything, I would eagerly pull out my phone to watch what was going to happen. How high would that measurement get? Would I experience a rapid glucose spike, or a more protracted and gradual one? What food or drink was the absolute worst for causing spikes, and how did my exercise and daily routine affect my numbers? Are there any foods I could eat before a carb-rich meal that might help smooth out the glucose spike?
Very quickly I started noticing some obvious trends and patterns...and it's these revelations that I most wanted to share...
1. The absolute worst glucose spikes happen... when I ingest high-carb meals or drinks on a completely empty stomach. This is notably worse for drinks. The worst spike I have had over the entire time I've worn the CGM (more so than any ice cream, pasta, bagel, cookies, or pizza), was when I drank a full glass of oat milk on an empty stomach. Let me say that again, OAT MILK. Not gatorade or can of sugary soda....but OAT MILK...something considered by many as a "healthy" beverage choice. What also really surprised me was how even a single food item (like one single small cookie) could obliterate my blood glucose if I ate it on an empty stomach.
What I did about it: The habit that developed was that any time I knew I had an empty stomach, I would be careful about what I ate first. I now actively try to find ways to slow the digestion of those quick carbs. This typically means either eating something oily, fatty, or high in fiber BEFORE eating or drinking any significant carbs. I also now start every breakfast with a full glass of water (and my coffee), before eating any cereal. I have also recently found a few new cereal brands that are notably lower in carbs, but just as delicious. The last two weeks I have been eating a cereal known as "Three Wishes", which I sprinkle with a spoonful of high-fiber chia seeds. This single change alone dramatically improves my morning glucose levels. This entire experience has also just been quite revealing and my mentality over meals has simply shifted. The thought of eating something like two or three Oreo cookies on an empty stomach makes me quite uncomfortable knowing what it would undoubtedly do to my blood sugar. Yet, from a big picture view, eating a couple of Oreos as a snack doesn't really seem that ridiculous....does it? These are the types of observations and habits that the CGM made me really come to notice and appreciate.
My infamous "oat milk spike"
Glucose spike after a SINGLE small cookie
(on an empty stomach)
2. Processed or highly refined starches are also really problematic for me. I LOVE a good bagel or sandwich...but white or refined flour annihilates my blood sugar, as do other snacks that are white-flour based or highly refined (like pretzels or crackers). A single plain bagel immediately spiked my glucose over 155 mg/dL. Ironically, had I eaten a fatty cream cheese with it, my spike may have been more gradual.
6 AM breakfast spike (w/old breakfast habits)
Note the quick onset
7 AM breakfast "bump" (after changing habits/diet)
Note the more protracted bump and no spike
3. Liquids are the worst! I've already noted this, but I've become extra aware of liquids. I only drink non-sugared drinks. I have always been pretty good about this and don't drink sodas or sugary teas, but there are other drinks that many simply don't think about. That delicious chai or caramel latte? - loaded with sugar. A glass of healthy oat milk? - loaded with carbs. Iced coffee with a single pump of sweetener and maybe topped with a dollop of whipped cream? - loaded with sucrose. You get the idea. One anecdote to share: On many of my long runs I will often drink a single bottle of Tailwind sports drink....and that also spikes my glucose drastically (even while in the middle of running upwards of 20 miles!)
What I did about it: I am very careful about my liquids now. I try to stick to water or beverages sweetened with non-caloric natural sweeteners like stevia or monk fruit. If I do order a "named" drink at a cafe like a "london fog tea", I make sure to ask for stevia in place of sugar. In general, I also just try to hydrate more. I'm now that guy that carries a re-usable stainless steel water bottle everywhere.
4. Snacks! Snacks have always been my weakness. I love to snack and have always known it was not a great habit. What's more, is that when I would snack, I was often turning to those refined carbs. Why yes! I would love a bag of pretzels to snack on! I've really noticed a change over the past few weeks simply by moving to more filling snacks like nuts or nut butters. Another interesting (although tangential) data point is that I never truly realized how much I snacked until I started an Invisalign treatment for my teeth last year. Having to wear the Invisalign trays made snacking a real pain to deal with. Every time I'd want to eat something, I'd have to take the trays out, and then brush and floss after the snack. I often found that I would just skip the snack and wait until meal time instead to avoid all the trouble. I can tell you that I have never lost so much weight, so fast, as I did for that year+ with those Invisalign trays (The Invisalign Diet is real!!). Turns out, the reason I wasn't losing weight before the Invisalign (and despite running 50 miles a week) was because I snacked.... A LOT!
What I did about it: In general, I try to eat more hearty meals with more oils, protein, fats, or fiber. These keep me full and keep the temptation to snack in-between meals, away. If the one bowl of high-grain (low-sugar) cereal doesn't adequately fill me at breakfast, I might top it with an egg, avocado, or a thin slice of seed bread with peanut or almond butter. Then, I am usually not hungry again until lunch. Before I eat my dinner I will often drink a full bottle of water (sometimes with some chia seeds thrown in) to help slow digestion and temper my hunger. One important thing to note is that snacks like nuts or cheese can be really high in fats--which is also not good in high volumes--so I'm definitely not advocating for just eating tons of fatty foods.
5. Moving is key! Yes it is true that I run upwards of 50 miles per week...but I also learned quickly that I was often NOT moving DIRECTLY after my meals. This is a really bad habit when trying to control blood glucose. One of the best ways I found to smooth out glucose spikes was to simply move around a bit after a big meal. Even just a few minutes of walking greatly reduced my glucose spikes.
What I did about it: The most notable change I made was to deliberately move after meals. At breakfast, I now walk my dog immediately after eating so that it eases any potential spike. At lunch, I will get up and go for a short walk (or plan my daily run for right after lunch). At dinner, I simply try to eat earlier and then either walk the dog again, or simply move around the house more purposefully. I sometimes delay an evening run until after dinner as well. I'm convinced the worst habit in this regard is to simply eat a big meal...and then just veg-out on the couch (especially if that meal is very late in the day).
In Summary...
I look forward to re-checking my A1C values again after the holidays to see if my efforts have helped bring my average blood glucose numbers down. Regardless of what happens though, I can definitely say that I am now eating healthier and living with better habits overall. Cutting out starchy snacks and being hyper-aware of my empty-stomach foods and beverages has had the most dramatic effect on my levels. I don't feel like I've lost much in this process either. I do still treat myself to some sweets...I am just more aware of how much I eat, and when I eat.
Another piece of interesting data I've pulled from this experiment comes from my Garmin watch. I wear my watch to bed so that it can track my heart rate and sleep data. For the past few weeks, I have had the highest HRV (heart-rate variability) and sleep scores for the entire year. I consistently score over 85 for my sleep (was typically 75-80), and over 50 for my HRV (has typically been around 40). Additionally my quality of sleep cycles has improved. I have also noticed that my "stress" scores are much lower (although I do think that this is somewhat of a fuzzy and unscientific measurement coming from my watch). All-in-all, my body seems to be liking my new habits (at least over the short term). I think I'll really need to see how things shake out over the course of the next year to truly get a sense of any overall health benefits.
Lastly, if you're curious about what it's like simply wearing the CGM...I can tell you that I completely forget it's even there. Applying the sensor for the first time did come with a very slight needle prick (akin to maybe a vaccine shot), but once in place, I never feel it. I definitely don't walk around feeling like there is a needle constantly stuck in my arm...I genuinely don't notice it and it stays on in the shower.
An applied CGM Sensor on the back of my arm
(shown with additional waterproof "over-patch")
A few notable caveats:
First, CGMs aren't cheap. A single Stelo brand CGM costs $50 and lasts for 15 days....meaning it costs $100 a month to wear these sensors. I used my HSA to pay for the first 2-pack, but I'd prefer not to continue tapping into those HSA funds for this "experiment" should I choose to continue.
Second, they aren't perfect. The accuracy is less than that of a prescription CGM and definitely less than a direct finger-prick blood test. I ran several comparative tests against finger readings and the CGM consistently reads about 5-10 points higher (even during fasting). For someone like me that is not as concerned about absolute values, and more about trends, this isn't a big problem. IF I were using a CGM as a true diabetic, I would absolutely get a prescription-level device that is more accurate and then calibrate it often with direct blood tests.
Third, they can glitch out. For the first 24 hours of wearing the device, the measurements were all over the place. I learned that this is very common and it typically takes about 24 hours for the device to "settle down". This is somewhat annoying given that each sensor only lasts about 15 days....so losing an entire day to unreliable data is notable. Additionally, those wonky measurements on the first day can skew any long-term averages that you are actively tracking.
Chaotic readings on the first day of a sensor
Fourth, sleeping directly on the device can lead to "pressure failures" and cause it to lose connection and not report glucose data. This means that you have to be careful if you are a side sleeper. Some people have noted that they wear their sensors on their abdomen for this reason, with the caveat being that the device is "not officially FDA approved to be worn anywhere but on the back of the arm"...so any measurements from an alternate site may not be a as trustworthy.
Lastly, the CGM doesn't actually last 15 days. In most cases, the CGM starts having read failures by day 14 (meaning you really lose two days per sensor if you count the first "chaotic" day of readings).
Given all of these caveats, I still think that it has been worth it tracking my numbers and learning what I've learned. I am uncertain if I will continue to wear a CGM longer term, but the insights I have gained, and new habits I've formed thus far, have been invaluable.
Here is a link to a helpful glycemic index reference chart for common foods and snacks:
...and now I'm off to my physical therapist to deal with this nagging back pain.....sigh
