Impossibly-volatile and seemingly-random variations in C/I ratios

You sound very knowledgeable when it comes to your diabetes. I am also on the leaner side and I am very sensitive to insulin with a TDD of ~ 27 units using MDI. I have narrowed down my basal and carb ratios with lots of trials and tribulations. My diet is high in protein and carbs range anywhere from 120-150/day. ALL carbs should be counted since vegetables can have a carb content but may take longer to absorb. I treat them as typical carbs in my calculations because I typically have more than 300g of veggies per meal.

Protein and fat present their own set of issues. My typical meal has about 180-270g of protein with about 40g of carbs. The following is a rough guide that I have modified to meet my own needs based on my individual needs, MDI, diet, and exercise.

If eating > 40 g fat and > 25 g protein with a carbohydrate (CHO) meal increase the calculated ICR meal dose by 30-35%

  • For insulin pump: deliver 50% of this new dose (usual dose + the increase) as a normal pre-meal bolus and 50% as square/extended wave over 2 - 2.5 hours
  • For MDI: administer 50% of this new dose (usual dose + the increase) as pre-meal bolus and 50% as post-meal bolus 1 - 1.5 hours after the meal.

Assess the glycemic response and adjust the following as required:

  • The pre-meal bolus:post-meal ratio ( 60:40, 50/50, 40:60, 30:70 …) AND/OR
  • The duration of post-meal insulin delivery (3, 4, 6 hours,…)
    This works for me and may or may not work for you. There are many technical formulas out there to account for protein and fat but it will make you crazy. See what you think.
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Well, i should clarify. The time-to-onset (of a BG reaction) varies, but then the steepness of the trajectory seems not to. Once i’m rising, i’m really rising, whether it was puy lentils or orange juice. The latter kicks in quicker than the former, but i’ll rise at a similar rate, particularly if non-bolussed. Would one expect that? I was led to believe something like the former would cause a slow, gradual rise, and the latter a sharp spike. I get spikes with everything… but only time for them to occur seems to vary.

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Yes, we are not good comparisons, because all carbs cause my son to rocket high at a steep curve without insulin. So maybe similar to you if others are different. We never see slow gradual rises without insulin.

Not in the slightest, unfortunately.

Herein we start to diverge already. My TDD can be anything from 25u to 65u… with little difference in intake or conditions. My breakfast (so indentically repetitive every day it now bores me to tears) used to require 2u, during the week. I had to take 9u this morning, to keep my BG under control, and this included a spike to 12mmol, depsite a 3u pre-bolus 30min prior to eating. (i’d have hypo’d heavily earlier in the week). It’ll probably be back to 2u in a few days… and i’ll be pre-bolussing 4u, and hence will get a kick in the teeth of a hypo. It’s these random swings that make sensible calculated and experice-based management (how the rest of my life runs) frustratingly impossible.

My diabetic nurse tells me the opposite. (300g of veggies for meal sounds a lot, incidentally…a lot of that will surely be water?)

I just wish i could use a regime like this, but it’s pointless. I might spend days/weels working out some ratios that will work for just a few days, then they won’t, and it was a big waste of time that i could have spent more productively.

Apologies for sounding flippant, but i’ve just had enough of today. i’ve injected 19u of bolus so far for just 90g of CHO, and averaged a BG of around 8mmol. Just nothing works today.

(it might be my switch-to-Levemir still bedding in, but i’ve been raising it and raising it…started on 6u & 8u and i’m now on 8u and 12.5u… yet still running way too high)

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It depends on the type of vegetable and how carb sensitive you are. Often I don’t count carbs in vegetables, because their carb content is so low. Considering the high amount of carbs in rice or pasta, carbs in vegetables usually contribute no more than a rounding error to the total amount in my dinner.

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Sounds like the switch to Levemir has caused you all sorts of problems. This is not uncommon. Many T1D find that a much higher dose of Levemir is needed, does not last 24 hours, and there are peaks and valleys in it’s curve leading to high blood sugars and hypoglycemia. It appears that you already have split the dose. Studies of levemir show that the duration of action can range widely from 5.7 hours at the lowest doses to 23.2 hours at the highest doses. It does not have a consistent flat line over 24 hours as promoted. You should reach a steady state after 3 doses of Levemir. I personally have not had good experiences with Levemir. I currently use degludec (Tresiba) which I find wonderful with a flat line overnight taking 11u at dinner. I would be very interested in seeing your trends over a 1-2 week period.

I agree that it can be incredibly frustrating especially when products do not perform as promoted in the studies. It is clear that levemir has such a wide range of duration depending on the dose.

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