I do think you’ll need to use a different method to get at this, if you want to. (But I appreciate how annoying it is when it’s hard to bleed! I ended up being a bit brutal sometimes, since I had to remove the safety on the lancet… In retrospect I should have tried a lower gauge.) The freestyle was almost always lower than test strips for me, it’s a great tool for local data changes but just got much systemic bias for a global data attempt.
That was my conclusion, too (going deeper hurt more than it helped), but local stores don’t seem to carry lower-gauge lancets, and online they are sold in boxes of 100…
I’m about due for a check-up anyway, should include fasting glucose and A1c.
Just had a look at the A1c values from lab tests done over the past few years, and there’s no trend or seasonal pattern of any kind (all values are well within the margin of error).
Here’s another “discovery” that turns out to be a well-known effect. This chart shows my responses to eating pizza in different situations; the highlighted series is eating pizza yesterday after having a drink (the two obviously bad responses are eating pizza while being immobilized in a meeting room).
I think this study requires more funding
The A1c from my latest blood-testing extravaganza is unchanged from previous years, so the lower values are likely an artifact.
Did another two-week round earlier this month; here’s what I learned:
- Unlike oatmeal, microwaved oat bran appears to be an unproblematic breakfast for me.
- Eating an entire batch of home-made palmiers for afternoon tea isn’t ideal.
- Turns out Worcestershire sauce can contain quite a bit of sugar.
Here’s the data from a day I went skiing: Note the response to eating half a bar of chocolate while skiing, and then eating the exact same amount of chocolate again right afterwards, before driving home. Also note the blood sugar drop after taking a brief hot shower, which may or may not be a coincidence…
i use freestyle libre. i have over 1 year data as i am a type 2 diabetic. how are you tracking the activity to overlap with the BG levels? i am very curious.
The activity level is based on hourly step counts from Fitbit. I have a Jupyter Notebook I use to plot this data; you can download it from the bottom of this blog post.
You can also log activity in the Libre app and it will show up in your exported data. If you’re doing more than basic exploratory analysis, you may need to interpolate the Libre data to estimate your BG at same time as the logged activity.
Thanks for the write up and for the notebook!
I have all my data in other places than you (glucose reading / notes in Spike-App and steps counts in Apple Health). Im going to see if I can plug it in and use your graphs. Ill share if I end up doing it.
Just started another two-week round of blood sugar tracking: I’m curious if the reduction in exercise since March (~30% fewer steps per day on average, and no weekly gym or pool workouts) is translating to poorer blood sugar responses overall. Plus I’d like to see if my blood sugar responses to some some new take-out food options (and new deserts I prepare at home…) are about as expected, or if there are any surprises…
What I learned:
- The reduction in the amount of exercise over the past few months has not made my blood sugar responses worse in any obvious way.
- Meals containing white rice (or rice flour) continue to be least ideal as far as blood sugar is concerned, as is eating anything (sandwiches, ice cream, potato chips) before sitting in a car for extended periods of time.
- Most other things I did seemed just fine, including eating chocolate brownies, or drinking lemonade…
Have you tried resistant starch methods of cooking to see if it reduces the effects. Refrigerating a potato after cooking or mixing oil in with rice before cooking?
I do sometimes have leftover rice or pasta, but it’s not obvious that blood sugar responses to the reheated meals are better. Can’t say for sure, as it’s usually not a fair comparison (different quantities, sides etc), but I’ll definitely keep this in mind next time!
Just finished another two-week FreeStyle Libre sensor, no big surprises:
- The least optimal blood sugar responses continue to be meals that can’t be digested fast enough. Perhaps the insulin response has a limited time window?
- Unlike regular rice, basmati/long-grain rice appears to be unproblematic.
- Chocolate cake is fine, but don’t eat the whole melon.
Readings were a bit on the low end of plausible (by about 10mg/dL). Don’t have any blood tests to compare against, but relative changes were about as expected.
As an actual type 1 diabetic that has been wearing a CGM for years, the amount of continuous glucose data I have is probably very plentiful. However, because I am a diabetic, it means values are much more sporadic and not controlled. Interesting seeing non-diabetics use CGMs. I did not know anyone did that
I believe I am seeing the same thing, Eric. In general, when I cut my processed carbohydrate (including grains like rice and, yes quinoa) intake to about half a serving – that’s ~1/8 cup/22 g for whole grain rice, for example – the bump in BG is very small. Often it doesn’t even hit 100 mg/dL.
The conundrum inherent in this small portion approach is that it makes it harder to, at the same time, minimize my time restricted feeding (TRF) window, eating only during daylight hours (circadian) etc. I had no trouble staying at my desired weight (which is at the lower range of published “normal”) on a 16-8, 18-6 schedule. Not so since I have been wearing a FreeStyle Libre and tracking closely. I have gained an unwanted 5 kg and am frequently “hungry.” But most days, my BG is this satisfying, almost straight line.
So much to learn!
Eric uses the Freestyle Libre, which is available in the US with a doctor’s prescription or through various wellness services (with a high markup), but can also be acquired from friends in Europe, where it is available over the counter.