Hybrid Closed Looping with #OpenAPS – eat what you like and no need to worry…. #wearenotwaiting

Hybrid Closed Looping – eat what you like and no need to worry…. #wearenotwaiting
Hybrid Closed Looping – eat what you like and no need to worry…. #wearenotwaiting

One of the things that I’ve previously described Closed Looping as is automated sugar surfing, and I’d still stand by that description, especially when you look at the results it’s produced for me over the last few months. The best bit of if it is that it works regardless of what you eat. No necessity for low carb here (although, if you’re gluten intolerant, then you may find that you have different priorities).

First up though, knowing that I now had my very own hybrid closed loop watching my back, I think it’s fair to say that I’ve not been all that careful about what I eat. In fact, I’ve not been remotely careful. Knowing that there’s a system sitting there in the background with a sole aim of getting you to a target glucose level is really quite reassuring. And so it has proven.

My carb intake over the period has been a rather spectacular average of 196g per day. That includes one day where there was a maximum of over 500 (let’s just call that one a bad day…). I have also been carb counting as I would expect to and bolusing accordingly. So over this period of time, what has that resulted in? The stats for the period are:

Now given my profligate ways and relatively large amounts of (sometimes rather fast acting) carbs, the prediction for my Hba1C is exactly the same as the last one I did before going into looping full time. That’s a pretty impressive result, given that I’ve been eating like a pig and will continue to do so over Christmas.

The range that this is shown at is 4mmol/l to 10mmol/l, as is consistent with the studies that are regularly undertaken relating to CGM, and we see that of my 7% of time spent below 4mmol/l, the median value is 3.5mmol/l. This is typically taken as being the clinical point of Hypo onset, so we can fairly say that I’ve been Hypo in this period for 3.5% of the time. I know that a number of those readings are at sensor end and are lower than bloods show.

The highs (more than 10mmol/l) account for 10% of the time, although if I was to pull this in more tightly, which is what I prefer, it’s really 17% of time above 8.8mmol/l, although not massively above that level.

Finally, this is the AGP for the period.

My commentary on this one is that it’s clear where the carbs cause issues. Eating late and having carbs for lunch spreads my AGP far wider than I’d like it to be. Realistically, as reflected in the stats, where my average is 6.7mmol/l, but my standard deviation is 2.4 mmol/l (or 36% of the average), I’m a little outside of the 33% target. The best results I’ve ever had come from low carb, for fairly obvious reasons, and I definitely lose more weight that way, but these aren’t bad.

Is it terrible? No, it’s not. Throughout the time period, I’ve had very few extreme highs and no severe low.

The other thing I’d note on the patterns shown above – I have a rather too high incidence of the Dexcom app just “stopping” overnight, or suffering signal loss. This has meant on a number of occasions where I was expecting the loop to take me down overnight, it instead stopped and left me where I was. Not ideal.

Coming back to the straight data presented then, what does a Hybrid Closed Loop mean in terms of eating? It means that you can achieve very good results without worrying massively what you’re eating, as long as you manage food and insulin sensibly. Low carbing is not a requirement for looping. Not a requirement at all.

Once again, it’s another little slice of freedom regained!


  1. Hey Tim, while I understand that closed loop has done a great job at keeping BG in range and this means you can be more relaxed in regards to carbs effects on Blood Sugars.
    I am intreated to hear how do you feel? While running Open Loop my BG range has been similar to yours (but not as good) I have noticed that if I do relax with my carb intake personally I really feel it in a bad way.

    • It’s fair to say that different types of carbs have different effects. Sticking to traditional “good” carbs seems fine. I’m okay with brown rice, potatoes, pulses, etc. The more refined stuff really isn’t, and results in often feeling bloated.

      So while I’ve been able to eat pretty much what I like, the type of carbs seems to matter as to feeling of well being.

1 Trackback / Pingback

  1. Popping The Bubble - Type1Bri.com - A Diabetic Blog

Leave a Reply

Your email address will not be published.