Insulin to carb ratio

Just out of curiosity, what is everyone’s insulin to carb ratio? I inject 1 unit of insulin for every 5 grams of carbs

Raven, this is one of those things that varies all over the map, so it can be interesting to know what other's numbers are, it isn't particularly helpful in judging your own.

That said, T1s, generally, will have higher ratios than T2s, who usually have Insulin Resistance. Typical IC for a T1 is in the range 1:15-30 although it is not uncommon for a T1 to have an IC in the 1:10-15 range. T2s are usually in the 1:4-10 range.

However, IR is not particularly rare among T1s, so T1s with T2-like insulin needs show up around here all the time, and we have some regulars with T1 and IR.

Finally, this ratio is not static, but is constantly fluctuating through the day, week, month, illness, stress, and on and on. You can have an IC 1:15 at lunchtime, 1:12 in the evening, fairly consistently. This is one of the things that makes pumps such effective tools in tightening control -- they can be programmed with all these variations, and take care of calculating the right insulin dosing based on these varying factors.

I have t1 and my insulin to carb ratio on the pump varies by time of day. 1:12 - 1:14 - 1:15. I run lower basal rates - so one unit does not cover a lot of carb. So I echo everything Dave has said. I am type one - and the spikes are worse in the morning for me. I have and continually test my basal rates so that these are pretty much low - but carbs just drive my numbers up. Symlin and or Victoza has helped me to not have as high a spike - as well as using an extended bolus on occasion with the pump.

How did you conclude the typical T1 range is 1:15-30? In all the discussions I've seen on this issue, that tends to be the range primarily of those honeymooning and in the early stages of LADA.

LADA here. Sensitive to carbs and to insulin but my IC is 1 to 6 or 1 to 7. Insulin sensitivity = 1 unit of insulin lowers my BG 65 points for corrections. 16-25 units DD.
As we say here, your diabetes may vary. Everyone is different. Difficult to make general statements.

I’m a type 1 diabetic, I was diagnosed when I was 14 and I’m just now trying to really learn about it, so you guys are teaching me a lot :stuck_out_tongue: thanks. I know everyone is different, was just curious to see what everyone had to say :slight_smile: learning about everyone else’s diabetes is pretty cool

I know this is not the norm or even 'recommended' in most cases, but I don't count carbs and have no idea what my i:c ratio is. I bolus based on judgement of the type and amount of food I eat. I do avoid all grains, sugars and simple carbs and eat a lot of the same food every day, mostly meat and vegetables, so that helps. I have gotten pretty good at guessing as I am usually able to maintain fairly normal bgs including post prandial. most of my meals require 2-4 units of insulin, more in the morning less in the evening.

Anybody else follow a similar dosing regimen?

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By reading what T1s post here, on other D sites, and peer-reviewed papers.

Raven, I hope I didn't come off as critical of your question. It's a very good one for anyone trying to learn about how to manage this condition.

Mainly I just wanted to "set the stage" for how relatively meaningless other's ratios are as applied to one's own situation, but a good question just to get a better "feel" of what the landscape among us looks like out there -- which is what you were looking for :-)

I'm T1(LADA)use 1:13 morning and afternoon, 1:15 evenings. Honestly, as others have said, it will be all over the map depending on many factors, age, fitness level, duration of the disease, diet, etc.
Use the amount of insulin you need to meet you and your doctors goals, don't base your dosing on what someone else does.

Hmm, the posts below would seem to indicate it's not the case.

Currently operating on 1:15, though that's probably more accurately thought of as 1:15-1:20. But I'm pretty unusual, either more than a decade of LADA honeymoon or, more likely, some MODY variant, so my case should have even fewer implications for most folks.

T1 here. 1:12 from midnight-10:30AM and 1:16 any time after 10:30AM.

Mine is 1u:7.5g carbs (at all times of day).

I'm not at all insulin resistent (160 lb guy, sensitivity factor of 1u:65 mg/dl)

I'm not sure why my bolus ratio is stronger than others, but I do enjoy reading these kind of comparison discussions, and I sometimes wonder if we could all get a better understanding of how these things work by more systematically comparing with the community.
(And I don't think we need to worry about there being some sort of personal judgement inherent in making dosing comparisons!)

EDIT: forgot to say, I'm a T1, two years in. :)

I use three ratios. 1:14 at breakfast, 1:22(ish) at lunch, and 1:16 at dinner.

Newly LADA, probably still honeymooning. I currently use 6U Lantus at night for my basal. I've not done too much figuring for correction doses (I rarely use them) but I generally think of a correction as 1 unit for 100 points drop. TDD runs around 15-16U.
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1:5, 1:6, 1:8 breakfast lunch dinner ISF approx 40pts/u

Keep in mind that a correction is only removing glucose from the blood; a meal bolus is dealing with a situation where glucose is being added to the blood from digestion while you're removing it with insulin.

Blood glucose dynamics are much more complicated than the simple linear model we all use to manage our condition. For example, when digesting there are other hormones secreted by the stomach that affect the pancreas and liver altering the processing of BG. In fact, it is the pancreatic stimulatory aspect of these other signals that led to drugs like Byetta and Victoza for treating T2 diabetics.

As such, it's actually quite common to have a correction factor and an IC that don't "match up" -- i.e. 1U for 10g of carbs works for eating, but if you don't cover it those 10G raise your BG 100mg/dl, yet paradoxically you can drop that 100 rise with 2U (less sensitive at higher BG).

What's going on with all the relevant organs and hormones when your digesting is vastly different than when you're in fasting mode (>2-3hr after eating), so insulin behaves a bit differently too.

This is from the Actual Pump Practices Study in 2007 of 900 Deltec Cozmo Type 1 pump users. Carb ratios of 1:10 seems to be the most common at about 20% of users. 55% have ratios less than or equal to 1:10, 45% are greater than 1:10. This is from John Walsh's

This is great! I found another copy of it with a bit more information in a PowerPoint:

1:12 MN to 10:30AM, 1:15 10:30AM-MN. Insulin sensitivity factor 1:100 from 9PM-6AM, 1:90 from 6AM-9PM. So, fairly insulin sensitive for corrections, but also pretty carb sensitive. Female, approximately 125 pounds, 7 years as Type 1.