Time in Range

I have been a type 1 diabetic for about 2 years and am still a little confused about “time in range”. I know blood sugar swings are not good for my heart (and give me a massive headache), but what should I set my range to be? Right now I have my Freestyle Libre app set for 70-140. I am normally 60-85% in range with this setting. I looked up the topic on this forum and a lot of people have their range set to 70-180. Am I setting it too low?

We do focus on the recommended range of numbers as our goal, but it’s important to focus on our own body’s needs.
Some people are fine at 80, while others may not feel they’re alert enough to do the things they need to do - or like me they need to leave some wiggle room on the lower end for various reasons. In my case I have to climb a couple of flights of steps to get to my car. It’s random and often spontaneous, and stair climbing makes me drop, so I aim to keep my low number in the 120s. My high is set for 180, which is considered the acceptable high end number (my term). People who set it at 140 may be shooting for tighter control but for me a higher number on the upper end of the scale is more achievable and gives me some wiggle room with my boluses - even the best carb counts can go wrong sometimes.
Consider your lifestyle factors, how well you function at various levels, and whether you need a cushion; that will help you determine if it would be wise to aim a little higher on the low end so you’re doing what’s best for your own body.

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Hi [homeschoolingmomof5] The 70 would be on the low side for me and I suspect most people. 70 is fine but if it goes lower there is a problem. If my sugar was in the 70’s and and I had just eaten something and I was sitting at my desk I would not be concerned. I would check every 15 minutes by looking at the readout on my pump. If I was out walking or doing anything active I would grab some carbs quickly. For me it is possible to drop 30 to 40 points quickly. 70 would be like going to the precipice of a steep cliff, a little further and you’re in big trouble. I would not worry too much about the actual percentages. It would be best if you could be in range for 100 % but that is not humanly possible. In the short term going too low is much more dangerous than too high. I would suggest double checking the range with your endocrinologist and then do the best you can. Some days or weeks are better than others. Just be careful of patterns if you tend high or low at any particular time or after a particular activity you can adjust your meds and or your eating.

@homeschoolingmomof5 Courtney, you are correct in not wanting your BGL to be spiking as that could hurt much more than your heart. “Medical experts” have established a BGL In-Range of 70 - 180 mg/dl and suggest that a person with diabetes should fall in-range no less than 70% of the time, and people without diabetes greater than 95% of the time. It is common for humans to elevated BG following meals. What we don’t want to do is stay above 180 mg/dl for any more than briefly, and we never want to drop below 70 mg/dl especially when our BGL has been “high” minutes before.

That said, I have three In-Range settings that I use to monitor my efficiency. My AGP report has the standard range making it more convenient for medical providers to take a quick glance. My Dexcom has a 40% narrower range, split into two 12 hour segments - my 9:30 PM to 9:30 AM is 85 to 145 so I’m alerted is the algorithm predicts I will drop below 86 - my safety factor. My Tandem pump has a different range setting to accommodate Control IQ Exercise mode. When exercise mode is activated in CIQ, the pump algorithm attempts to maintain BGL between 140 & 160 mg/dl.

All that stuff may sound confusing, but activated these different ranges at different times and I feel comfortable.

Thanks everyone for the response! I do like to have tight control and my doctor is ok with it since I normally catch my falling blood sugar and correct in time. I have learned to be ok with higher numbers especially when my blood sugar sometimes goes haywire after eating - but I don’t like it. Dennis, thank you for the info on having different ranges for different times of day. I hadn’t ever thought of it that way!

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Most people use 70-180 but you should consult your doctor about it. I had a long talk with a medtronic rep and they were having employees test one of their new products and they used diabetics and non-diabetics and he told me that even the non-diabetics time in range averaged 88%. I found that very interesting since you would think the body would be at least upper 90s.

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Me neither. But, I don’t like going low or trending low even more. Both adversely affect how you feel physically, but for me, lows are even worse. If I go below 80 I start feeling pretty crappy, and I also need a buffer, so I try to shoot for 90-95 fasting.

I was diagnosed almost two years ago as well, age 33. I was extremely terrified and upset with highs, and was extremely frustrated with my body. So I was going low way too much. I’ve learned over time to get better at both not going low, and not freaking out about highs. I’m still trying to get better at this. My strategy now is to just keep highs as low as possible - whatever that means. If I never go over 130 after a meal, great. If my glucose gets out of control and goes over 180 or 200, I consider it a fail, but not as bad of a fail as a hypoglycemic episode. I correct, I keep close tabs on my carb amounts, food types, and insulin dosing and how these all affect me in particular ways, and I try to keep learning lessons as well as possible, including better strategies.

For ex., if a food spikes my sugar soon after eating, I know I need to bolus more and sooner before eating. If a food ramps up my blood sugar four hours after eating, I know I need to split my bolus more towards taking more insulin later. I try to prevent highs as much as possible, but since this also means needing even more so to prevent lows, sometimes it just works out that I’m having to correct a high after it happens, and wasn’t successful in preventing it.

If highs give you headaches (lows do this to me, pretty severely), again just try different strategies - different foods, or different insulin timings and dosings. Like the guy from the Arden’s Day podcast says, good insulin management is essentially all about TIMING + AMOUNT. They’re equally important. I always keep that in mind and try to get better at matching insulin curves w/ post-meal blood sugar curves. Anyway kudos on your good management and dealing with this tough disease!

I am newly diagnosed and my docs gave me a two month supply of the Libre 2 and Dexcom G6 to try. I ran both simultaneously for a month and found the Libre said my time in range was higher than my Dexcom. The Libre also gave me lower numbers when I was low (eg, said I was 65 when blood stick was 78). The Libre just seemed to err on low side. The Dexcom lagged by 10-20 depending on my rate of rise/fall arrow. But it never seemed to overestimate to correct itself like the libre did.

My doc said the Dexcom is more accurate for T1D and the libre is geared more towards T2D.

Take above with grain of salt as I’m new and still learning all this like you. This was just my experience.

For me I have mine set at 80-150. Sometimes my dex is spot on and it’s beautiful and I love every second of it but other times, it’s off by 20-30 points which is totally okay depending on where I’m at but if it says 150 I might not correct but my finger stick said 180, I’d definitely correct as long as it was appropriate with my IOB. I also try not to get too frustrated by my settings after a year of completely stressing myself out if I spiked over 150. I’ve learned to chill again and just look at my numbers as data and if there’s patterns that’s where I find this tight range most useful. Most of the time I’m averaging about 85% between 70 and 150, but I definitely have times where I spike in the mid 200s and sometimes low 300s but I do what I need to do to get back in range and that’s that.usually I can explain why too like carb counting just being off or hormone based stuff. I will caution since I’ve made my range tighter, I feel I go low more than I used to, but also with my settings at 80 I’m usually able to catch it before it drops too low which helps me treat with less carbs and have less of a rebound. Hope this helps!

I’ve been told 70% or higher is a good target for a 70-180 range.

Actually @don, the 70% TIR is the minimum percentage of time that a moderately managed person with diabetes should achieve.

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@don and @Dennis I’ve read the same things as Dennis, 70% is minimum aim for a 70-180 range and try to push higher. I’ve settled in the 85-95% range, though I go down lower time-to-time. However, I recently read the recently dx’d or people trying push higher should be careful of pushing too far too fast as doing so reportedly can cause retina/eye problems (burst vessels?) by abrupt changes; that it’s still a good goal, just achieve it more slowly. I’m no doc, so check with your Endo, PCP, eye doc and get the real scoop on how to approach.